MORPHOGEN-INDUCED NERVE REGENERATION AND REPAIR

Abstract: Disclosed are therapeutic treatment methods, compositions and devices for maintaining neural pathways in a mammal, including enhancing survival of neurons at risk of dying, inducing cellular repair of damaged neurons and neural pathways, and stimulating neurons to maintain their differentiated phenotype. In one embodiment, the invention provides means for stimulating CAM expression in neurons. The invention also provides means for evaluating the status of nerve tissue, including means for detecting and monitoring neuropathies in a mammal. The methods, devices and compositions include a morphogen-stimulating agent provided to the mammal in a therapeutically effective concentration.

Description: Morphoqen-Induced Nerve Regeneration and Repair BACKGROUND OF THE INVENTION The present invention relates to methods for enhancing the survival of neuronal cells in vivo and to methods, compositions and devices for maintaining neural pathways in vivo. More particularly, the invention provides methods for enhancing survival of neuronal cells at risk of dying, including methods for redifferentiating transformed cells of neural origin and methods for maintaining phenotypic expression of differentiated neuronal cells. The invention also provides means for repairing damaged neural pathways, including methods for stimulating axonal growth over extended distances, and methods for alleviating immunologically-related nerve tissue damage. In a particular embodiment of the invention, this invention provides a method for stimulating cell adhesion molecule expression in cells, and particularly nerve cell adhesion molecule expression in neurons. Finally, the invention provides means for evaluating nerve tissue stasis and identifying neural dysfunction in a mammal. The mammalian nervous system comprises a peripheral nervous system (PNS) and a central nervous system (CNS, comprising the brain and spinal cord), and is composed of two principal classes of cells: neurons and glial cells. The glial cells fill the spaces between neurons, nourishing them and modulating their function. Certain glial cells, such as Schwann cells in the PNS and oligodendrocytes in the CNS, also provide a protective myelin sheath that surrounds and protects neuronal axons, which are the processes that extend from the neuron cell body and through which the electric impulses of the neuron are transported. In the peripheral nervous system, the long axons of multiple neurons are bundled together to form a nerve or nerve fiber. These, in turn, may be combined into fascicles, wherein the nerve fibers form bundles embedded, together with the intraneural vascular supply, in a loose collagenous matrix bounded by a protective multilamellar sheath. In the central nervous system, the neuron cell bodies are visually distinguishable from their myelin-ensheathed processes, and are referenced in the art as grey and white matter, respectively. During development, differentiating neurons from the central and peripheral nervous systems send out axons that must grow and make contact with specific target cells. In some cases, growing axons must cover enormous distances; some grow into the periphery, whereas others stay confined within the central nervous system. In mammals, this stage of neurogenesis is complete during the embryonic phase of life and neuronal cells do not multiply once they have fully differentiated. Accordingly, the neural pathways of a mammal are particularly at risk if neurons are subjected to mechanical or chemical trauma or to neuropathic degeneration sufficient to put the neurons that define the pathway at risk of dying. A host of neuropathies, some of which affect only a subpopulation or a system of neurons in the peripheral or central nervous systems have been identified to date. The neuropathies, which may affect the neurons themselves or the associated glial cells, may result from cellular metabolic dysfunction, infection, exposure to toxic agents, autoimmunity dysfunction, malnutrition or ischemia. In some cases the cellular dysfunction is thought to induce cell death directly. In other cases, the neuropathy may induce sufficient tissue necrosis to stimulate the body's immune/inflammatory system and the mechanisms of the body's immune response to the initial neural injury then destroys the neurons and the pathway defined by these neurons. Currently no satisfactory method exists to repair the damage caused by these neuropathies, which include multiple sclerosis, amyotrophic lateral sclerosis (ALS), Huntington's chorea, Alzheimer's disease, Parkinson's disease (parkinsonism) , and metabolically derived disorders, such as hepatic encephalopathy. Current attempts to counteract the effects of severe traumatic or neural degenerative lesions of the brain and/or spinal cord have to date primarily involved implantation of embryonic neurons in an effort to replace functionally, or otherwise compensate for, lost or deficient neurons. Currently, however, human fetal cell transplantation research is severely restricted. Administration of neurotrophic factors such as nerve growth factor and insulin-like growth factor also have been suggested to stimulate neuronal growth within the CNS. (See, for example, Lundborg, (1987) Acta Orthop. Scand. 58:145-169 and US Pat. No. 5,093,317.) Administration of neurotrophic factors to the CNS requires bypassing the blood-brain barrier. The barrier may be overcome by direct infusion, or by modifying the molecule to enhance its transport across the barrier, as by chemical modification or conjugation, or by molecule truncation. Schwann cells also have been grafted to a site of a CNS lesion in an attempt to stimulate and maintain growth of damaged neuronal processes (Paino et al. (1991) Exp. Neurology 114(2):254-257). Where the damaged neural pathway results from CNS axonal damage, autologous peripheral nerve grafts have been used to bridge lesions in the central nervous system and to allow axons to make it back to their normal target area. In contrast to CNS neurons, neurons of the peripheral nervous system can extend new peripheral processes in response to axonal damage. This regenerative property of peripheral nervous system axons is thought to be sufficient to allow grafting of these segments to CNS axons. Successful grafting appears to be limited, however, by a number of factors, including the length of the CNS axonal lesion to be bypassed, and the distance of the graft sites from the CNS neuronal cell bodies, with successful grafts occurring near the cell body. Within the peripheral nervous system, this cellular regenerative property of neurons has limited ability to repair function to a damaged neural pathway. Specifically, the new axons extend randomly, and are often misdirected, making contact with inappropriate targets that can cause abnormal function. For example, if a motor nerve is dame 2d, regrowing axons may contact the wrong muscles, resulting in paralysis. In addition, where severed nerve processes result in a gap of longer than a few millimeters, e.g., greater than 10 millimeters (mm), appropriate nerve regeneration does not occur, either because the processes fail to grow the necessary distance, or because of misdirected axonal growth. Efforts to repair peripheral nerve damage by surgical means has met with mixed results, particularly where damage extends over a significant distance. In some cases, the suturing steps used to obtain proper alignment of severed nerve ends stimulates the formulation of scar tissue which is thought to inhibit axon regeneration. Even where scar tissue formation has been reduced, as with the use of nerve guidance channels or other tubular prostheses, successful regeneration generally still is limited to nerve damage of less than 10 millimeters in distance. In addition, the reparative ability of peripheral neurons is significantly inhibited where an injury or neuropathy affects the cell body itself or results in extensive degeneration of a distal axon. Mammalian neural pathways also are at risk due to damage caused by neoplastic lesions. Neoplasias of both the neurons and glial cells have been identified. Transformed cells of neural origin generally lose their ability to behave as normal differentiated cells and can destroy neural pathways by loss of function. In addition, the proliferating tumors may induce lesions by distorting normal nerve tissue structure, inhibiting pathways by compressing nerves, inhibiting cerbrospinal fluid or blood supply flow, and/or by stimulating the body's immune response. Metastatic tumors, which are a significant cause of neoplastic lesions in the brain and spinal cord, also similarly may damage neural pathways and induce neuronal cell death. One type of morphoregulatory molecule associated with neuronal cell growth, differentiation and development is the cell adhesion molecule ("CAM") , most notably the nerve cell adhesion molecule (N-CAM). CAMs belong to the immunoglobulin super-family and mediate cell-cell interactions in developing and adult tissues through homophilic binding, i.e., CAM-CAM binding on apposing cells. A number of different CAMs currently have been identified. Of these, the most thoroughly studied to date are N-CAM and L-CAM (liver cell adhesion molecules), both of which have been identified on all cells at early stages of development, as well as in different adult tissues. In neural tissue development, N-CAM expression is believed to be important in tissue organization, neuronal migration, nerve-muscle tissue adhesion, retinal formation, synaptogenesis, and neural degeneration. Reduced N-CAM expression also is thought to be associated with nerve dysfunction. For example, expression of at least one form of N-CAM, N-CAM-180, is reduced in a mouse dysmyelinating mutant (Bhat (1988) Brain Res. 452:373- 377). Reduced levels of N-CAM also have been associated with normal pressure hydrocephalus (Werdelin (1989) Acta Neurol. Scand. 72:177-181), and with type II schizophrenia (Lyons et al., (1988) Biol. Psychiatry 23:769-775.) In addition, antibodies to N-CAM have been shown to disrupt functional recovery in injured nerves (Remsen (1990) Exp. Neurobiol. 110:268-273). It is an object of this invention to provide methods for enhancing survival of neurons at risk of dying in a mammal. Another object is to provide methods for maintaining neural pathways in vivo at risk of injury, or following damage to nerve tissue due to mechanical or chemical trauma, a neuropathy, or a neoplastic lesion. Another object is to provide compositions and devices for repairing gaps in a neural pathway of the peripheral nervous system. Yet another object is to provide a means for redifferentiating transformed cells defining neural pathways, particularly transformed cells of neural origin. Another object is to provide a means for stimulating CAM expression, particularly N-CAM expression in a cell. Yet another object is to provide methods for monitoring the status of nerve tissue by monitoring fluctuations in protein levels present in nerve tissue, serum and/or cerebrospinal fluid. These and other objects and features of the invention will be apparent from the description, drawings, and claims which follow. Summary of the Invention The present invention provides methods and compositions for maintaining neural pathways in a mammal in vivo, including methods for enhancing the survival of neural cells. In one aspect, the invention features compositions and therapeutic treatment methods that comprise the step of administering to a mammal a therapeutically effective amount of a morphogenic protein ("morphogen") , as defined herein, upon injury to a neural pathway, or in anticipation of such injury, for a time and at a concentration sufficient to maintain the neural pathway, including repairing damaged pathways, or inhibiting additional damage thereto. In another aspect, the invention features compositions and therapeutic treatment methods for maintaining neural pathways in a mammal iii vivo which include administering to the mammal, upon injury to a neural pathway or in anticipation of such injury, a compound that stimulates in vivo a therapeutically effective concentration of an endogenous morphogen within the body of the mammal sufficient to maintain the neural pathway, including repairing damaged pathways or inhibiting additional damage thereto. These compounds are referred to herein as morphogen- stimulating agents, and are understood to include substances which, when administered to a mammal, act on tissue(s) or organ(s) that normally are responsible for, or capable of, producing a morphogen and/or secreting a morphogen, and which cause the endogenous level of the morphogen to be altered. The agent may act, for example, by stimulating expression and/or secretion of an endogenous morphogen. In particular, the invention provides methods for enhancing the survival of neurons at risk of dying, including protecting neurons from the tissue destructive effects associated with the body's immune/ inflammatory response to a nerve injury. The invention also provides methods for stimulating neurons to maintain their differentiated phenotype, including inducing the redifferentiation of transformed cells of neuronal origin to a morphology characteristic of untransformed neurons. In one embodiment, the invention provides means for stimulating production of cell adhesion molecules in cells, particularly nerve cell adhesion molecules (N-CAM) in neurons. The invention also provides methods, compositions and devices for stimulating cellular repair of damaged neurons and neural pathways, including regenerating damaged axons of the peripheral and central nervous systems. In addition, the invention also provides means for evaluating the status of nerve tissue, and for detecting and monitoring neuropathies in a mammal by monitoring fluctuations in the morphogen levels or endogenous morphogen antibody levels present in a mammal's serum or cerebrospinal fluid. As used herein, a "neural pathway" describes a nerve circuit for the passage of electric signals from a source to a target cell site. The pathway includes the neurons through which the electric impulse is • transported, including groups of interconnecting neurons, the nerve fibers formed by bundled neuronal axons, and the glial cells surrounding and associated with the neurons. In one aspect of the invention, the morphogens described herein are useful in repairing damaged neural pathways of the peripheral nervous system. In particular, the morphogens are useful for repairing damaged pathways, including transected or otherwise damaged nerve fibers (nerves) requiring regeneration of neuronal processes, particularly axons, over extended distances to bridge a gap in the nerve itself, or between the nerve and a post-synaptic cell. Specifically, the morphogens described herein are capable of stimulating complete axonal nerve regeneration, including vascularization and reformation of the protective myelin sheath. The morphogen preferably is provided to the site of injury dispersed in a biocompatible, bioresorbable carrier material capable of maintaining the morphogen at the site and, where necessary, means for directing axonal growth from the proximal to the distal ends of a severed neuron or nerve. For example, means for directing axonal growth may be required where nerve regeneration is to be induced over an extended distance, such as greater than 10 mm. Many carriers capable of providing these functions are envisioned. For example, useful carriers include substantially insoluble materials or viscous solutions prepared as disclosed herein comprising laminin, hyaluronic acid or collagen, or other suitable synthetic, biocompatible polymeric materials such as polylactic, polyglycolic or polybutyric acids and/or copolymers thereof. The currently preferred carrier comprises an extracellular matrix composition, such as one described herein derived, for example, from mouse sarcoma cells. Also envisioned as especially useful are brain tissue-derived extracellular matrices. In a particularly preferred embodiment, the morphogen is provided to the site as part of a device wherein the morphogen is disposed in a nerve guidance channel which spans the distance of the damaged pathway. The channel acts both as a protective covering and a physical means for guiding growth of a neuronal process such as an axon. Useful channels comprise a biocompatible membrane or casing, which may be tubular in structure, having a dimension sufficient to span the gap or break in the nerve to be repaired, and having openings adapted to receive severed nerve ends. The casing or membrane may be made of any biocompatible, nonirritating material, such as silicone or a biocompatible polymer such as polyethylene or polyethylene vinyl acetate. The casing also may be composed of biocompatible, bioresorbable polymers, including, for example, collagen, hyaluronic acid, polylactic, polybutyric and polyglycolic acids. In a currently preferred embodiment, the outer surface of the channel is substantially impermeable. The morphogen may be disposed in the channel in association with a biocompatible carrier material, or it may be adsorbed to or otherwise associated with the inner surface of the casing, such as is described in U.S. Pat. No. 5,011,486, provided that the morphogen is accessible to the severed nerve ends. Additionally, although the nerve guidance channels described herein generally are tubular in shape, it should be evident to those skilled in the art that various alternative shapes may be employed. The lumen of the guidance channels may, for example, be oval or even square in cross section. Moreover the guidance channels may be constructed of two or more parts which may be clamped together to secure the nerve stumps. Nerve endings may be secured to the nerve guidance channels by means of sutures, biocompatible adhesives such as fibrin glue, or other means known in the medical art. The morphogens described herein also are envisioned to be useful in autologous peripheral nerve segment implants to bypass damaged neural pathways in the central nervous system, such as in the repair of damaged or detached retinas, or other damage to the optic nerve. Here the morphogen is provided to the site of attachment to stimulate axonal growth at the graft site, particularly where the damaged axonal segment to be bypassed occurs far from the neuronal cell body. The morphogens described herein also are useful for enhancing survival of neuronal cells at risk of dying, thereby preventing, limiting or otherwise inhibiting damage to neural pathways. Non-mitotic neurons are at risk of dying as a result of a neuropathy or other cellular dysfunction of a neuron or glial cell inducing cell death, or following a chemical or mechanical lesion to the cell or its surrounding tissue. The chemical lesions may result from known toxic agents, including lead, ethanol, ammonia, formaldehyde and many other organic solvents, as well as the toxins in cigarette smoke and opiates. Excitatory amino acids, such as glutama€e also may play a role in the pathogenesis of neuronal cell death (see Freese et al. (1990) Brain Res. 521:254-264). Neuronal cell death also is thought to be a significant contributing factor in a number of neurodegenerative diseases, including Alzheimer's disease, Huntington's chorea, and Parkinson's disease, amyotrophic lateral sclerosis and multiple sclerosis. The etiology of these neuropathies may be metabolic, as results in hepatic encephalopathy, infectious, toxic, autoimmune, nutritional or ischemic. In addition, ethanol and a number of other toxins also have been identified as significant contributing factors in neurodegenerative diseases. The morphogens described herein may be provided to cells at risk of dying to enhance their survival and thereby protect the integrity of the neural pathway. The morphogens may be provided directly to the site, or they may be provided systemically. Alternatively, as described above, an agent capable of stimulating endogenous morphogen expression and/or secretion, preferably in cells associated with the nerve tissue of interest, may be administered to the mammal. In another aspect of the invention, the method disclosed is useful for redifferentiating transformed cells, particularly transformed cells of neuronal or glial origin, such that the morphogen-treated cells are induced to display a morphology characteristic of untransformed cells. Where the transformed cells are cells of neuronal origin, morphogen treatment preferably induces cell rounding and cell aggregation (clumping), cell-cell adhesion, neurite outgrowth formation and elongation, and N-CAM production. The methods described herein are anticipated to substantially inhibit or reduce neural cell tumor formation and/or proliferation in nerve tissue. It is anticipated that the methods of this invention will be useful in substantially reducing the effects of various carcinomas of nerve tissue origin such as retinoblastomas, neuroblastomas, and gliomas or glioblastomas. In addition, the method also is anticipated to aid in inhibiting neoplastic lesions caused by metastatic tissue. Metastatic tumors are one of the most common neoplasms of the CNS, as they can reach the intracranial compartment through the bloodstream. Metastatic tumors may damage neural pathways for example, by distorting normal nerve tissue structure, compressing nerves, blocking flow of cerebrospinal fluid or the blood supply nourishing brain tissue, and/or by stimulating the body's immune response. In another aspect of the invention, the morphogens described herein are useful for providing neuroprotective effects to alleviate neural pathway damage associated with the body's immune/inflammatory response to an initial injury to nerve tissue. Such a response may follow trauma to nerve tissue, caused, for example, by an autoimmune dysfunction, neoplastic lesion, infection, chemical or mechanical trauma, disease, by interruption of blood flow to the neurons or glial cells, for example following ischemia or hypoxia, or by other trauma to the nerve or surrounding material. For example, the primary damage resulting from hypoxia or ischemia-reperfusion following occlusion of a neural blood supply, as in an embolic stroke, is believed to be i munologically associated. In addition, at least part of the damage associated with a number of primary brain tumors also appears to be immunologically related. Application of the morphogen directly to the cells to be treated, or providing the morphogen to the mammal systemically, for example, intravenously or indirectly by oral administration, may be used to alleviate and/or inhibit the immunologically related response to a neural injury. Alternatively, administration of an agent capable of stimulating morphogen expression and/or secretion ijri vivo, preferably at the site of injury, also may be used. Where the injury is to be induced, as during surgery or other aggressive clinical treatment, the morphogen or agent may be provided prior to induction of the injury to provide a neuroprotective effect to the nerve tissue at risk. In still another aspect, the invention described herein provides methods for supporting the growth and maintenance of differentiated neurons, including inducing neurons to continue expressing their phenotype. It is anticipated that this activity will be particularly useful in the treatment of nerve tissue disorders where loss of function is caused by reduced or lost cellular metabolic function and cells become senesent or quiescent, such as is thought to occur in aging cells and to be manifested in Alzheimer's disease. Application of the morphogen directly to cells to be treated, or providing it systemically by parenteral or oral administration stimulates these cells to continue expressing their phenotype, significantly inhibiting and/or reversing the effects of the cellular metabolic dysfunction, thereby maintaining the neural pathway at risk. Alternatively, administration of an agent capable of stimulating endogenous morphogen expression and/or secretion in vivo may be used. In still another aspect, the invention provides methods for stimulating CAM expression levels in a cell, particularly N-CAM expression in neurons. CAMs are molecules defined as carrying out cell-cell interactions necessary for tissue formation. CAMs are believed to play a fundamental regulatory role in tissue development, including tissue boundary formation, embryonic induction and migration, and tissue stabilization and regeneration. Altered CAM levels have been implicated in a number of tissue disorders, including congenital defects, neoplasias, and degenerative diseases. In particular, N-CAM expression is associated with normal neuronal cell development and differentiation, including retinal formation, synaptogenesis, and nerve- muscle tissue adhesion. Inhibition of one or more of the N-CAM isoforms is known to prevent proper tissue development. Altered N-CAM expression levels also are associated with neoplasias, including neuroblastomas (see infra) , as well as with a number of neuropathies, including normal pressure hydrocephalous and type II schizophrenia. Application of the morphogen directly to the cells to be treated, or providing the morphogen to the mammal systemically, for example, parenterally, or indirectly by oral administration, may be used to induce cellular expression of one or more CAMs, particularly N-CAMs. Alternatively, administration of an agent capable of stimulating morphogen expression and/or secretion in vivo, preferably at the site of injury, also may be used to induce CAM production. CAMs also have been postulated as part of a morphoregulatory pathway whose activity is induced by a to date unidentified molecule (See, for example. Edelman, G.M. (1986) Ann. Rev. Cell Biol. 2:81-116). Without being limited to any given theory, the morphogens described herein may act as the inducer of this pathway. Finally, modulations of endogenous morphogen levels may be monitored as part of a method of detecting nerve tissue dysfunction. Specifically, modulations in endogenous morphogen levels are anticipated to reflect changes in nerve tissue status. Morphogen expression may be monitored directly in biopsied cell samples, in cerebrospinal fluid, or serum. Alternatively, morphogen levels may be assessed by detecting changes in the levels of endogenous antibodies to the morphogen. For example, one may obtain serum samples from a mammal, and then detect the concentration of morphogen or antibody present in the fluid by standard protein detection means known to those skilled in the art. As an example, binding protein capable of interacting specifically with the morphogen of interest such as an anti-morphogen antibody may be used to detect a morphogen in a standard immunoassay. The morphogen levels detected then may be compared to a previously determined standard or reference level, with changes in the detected levels being indicative of the status of the tissue. In one preferred embodiment of the invention, the morphogen or morphogen-stimulating agent is administered systemically to the individual, e.g., orally or parenterally. In another embodiment of the invention, the morphogen may be provided directly to the nerve tissue, e.g., by injection to the cerebral spinal fluid or to a nerve tissue locus. In any treatment method of the invention, "administration of morphogen" refers to the administration of the morphogen, either alone or in combination with other molecules. For example, the mature form of the morphogen may be provided in association with its precursor "pro" domain, which is known to enhance the solubility of the protein, dther useful molecules known to enhance protein solubility include casein and other milk components, as well as various serum proteins. Additional useful molecules which may be associated with the morphogen or morphogen-stimulating gent include tissue targeting molecules capable of directing the morphogen or morphogen-stimulating agent to nerve tissue. Tissue targeting molecules envisioned to be useful in the treatment protocols of this invention include antibodies, antibody fragments or other binding proteins which interact specifically with surface molecules on nerve tissue cells. Still another useful tissue targeting molecule is part or all of the morphogen precursor "pro" domain, particularly that of OP-1 or GDF-1. These proteins are found naturally associated with nerve tissue but also may be synthesized in other tissues and targeted to nerve tissue after secretion from the synthesizing tissue. For example, while the protein has been shown to be active in bone tissue, the primary source of OP-1 synthesis appears to be the tissue of the urogenic system (e.g., renal and bladder tissue), with secondary expression levels occurring in the brain, heart and lungs (see below.) Moreover, the protein has been identified in serum, saliva and various milk forms. In addition, the secreted form of the protein comprises the mature dimer in association with the pro domain of the intact morphogen sequence. Accordingly, the associated morphogen pro domains may act to target specific morphogens to different tissues in vivo. Associated tissue targeting or solubility-enhancing molecules also may be covalently linked to the morphogen using standard chemical means, including acid-labile linkages, which likely will be preferentially cleaved in the acidic environment of bone remodeling sites. Finally, the morphogens or morphogen-stimulating agents provided herein also may be administered in combination with other molecules known to be beneficial in maintaining neural pathways, including, for example, nerve growth factors and anti-inflammatory agents. Where the morphogen is intended for use as a therapeutic for disorders of the CNS, an additional problem must be addressed: overcoming the so-called "blood-brain barrier", the brain capillary wall structure that effectively screens out all but selected categories of molecules present in the blood, preventing their passage into the brain. The blood-brain barrier may be bypassed effectively by direct infusion of the morphogen or morphogen- stimulating agent into the brain. Alternatively, the morphogen or morphogen-stimulating agent may be modified to enhance its transport across the blood-brain barrier. For example, truncated forms of the morphogen or a morphogen-stimulating agent may be most successful. Alternatively, the morphogen or morphogen-stimulating agent may be modified to render it more lipophilic, or it may be conjugated to another molecule which is naturally transported across the barrier, using standard means known to those skilled in the art, as, for example, described in Pardridge, Endocrine Reviews 7:314-330 (1986) and U.S. Pat. No. 4,801,575. Accordingly, as used herein, a functional "analog" of a morphogen refers to a protein having morphogenic biological activity but possessing additional structural differences compared to a morphogen as defined herein, e.g., having additional chemical moieties not normally a part of a morphogen. Such moieties (introduced, for example, by acylation, alkylation, cationization, or glycosylation reactions, or other means for conjugating the moiety to the morphogen) may improve the molecule's solubility, absorption, biological half-life, or transport, e.g., across the blood-brain barrier. Among the morphogens useful in this invention are proteins originally identified as osteogenic proteins, such as the OP-1, OP-2 and CBMP2 proteins, as well as amino acid sequence-related proteins such as DPP (from Drosophila), Vgl (from Xenopus), Vgr-1 (from mouse, see U.S. 5,011,691 to Oppermann et al.), GDF-1 (from mouse, see Lee (1991) PNAS 88:4250-4254), all of which are presented in Table II and Seq. ID Nos.5-14), and the recently identified 60A protein (from Drosophila, Seq. ID No. 24, see Wharton et al. (1991) PNAS 88:9214-9218.) The members of this family, which include members of the TGF-β super-family of proteins, share substantial amino acid sequence homology in their C-terminal regions. The proteins are translated as a precursor, having an N-terminal signal peptide sequence, typically less tahn about 30 residues, followed by a "pro" domain that is cleaved to yield the mature sequence. The signal peptide is cleaved rapidly upon translation, at a cleavage site that can be predicted in a given sequence using the method of Von Heijne ((1986) Nucleic Acids Research 14:4683-469 * 1.) Table I, below, describes the various morphogens identified to date, including their nomenclature as used herein, their Seq. ID references, and publication sources for the amino acid sequences for the full length proteins not included in the Seq. Listing. The disclosure of these publications is incorporated herein by reference. TABLE I "OP-1" Refers generically to the group of morphogenically active proteins expressed from part or all of a DNA sequence encoding OP-1 protein, including allelic and species variants thereof, e.g., human OP-1 ("hOP-1", Seq. ID No. 5, mature protein amino acid sequence), or mouse OP-1 ("mOP-1", Seq. ID No. 6, mature protein amino acid sequence. ) The conserved seven cysteine skeleton is defined by residues 38 to 139 of Seq. ID Nos. 5 and 6. The cDNA sequences and the amino acids encoding the full length proteins are provided in Seq. Id Nos. 16 and 17 (hOPl) and Seq. ID Nos. 18 and 19 (mOPl.) The mature proteins are defined by residues 293-431 (hOPl) and 292-430 (mOPl). The "pro" regions of the proteins, cleaved to yield the mature. morphogenically active proteins are defined essentially by residues 30-292 (hOPl) and residues 30-291 (mOPl). "OP-2" refers generically to the group of active proteins expressed from part or all of a DNA sequence encoding OP-2 protein, including allelic and species variants thereof, e.g., human OP-2 ("hOP-2", Seq. ID No. 7, mature protein amino acid sequence) or mouse OP-2 ("mOP-2", Seq. ID No. 8, mature protein amino acid sequence) . The conserved seven cysteine skeleton is defined by residues 38 to 139 of Seq. ID Nos. 7 and 8. The cDNA sequences and the amino acids encoding the full length proteins are provided in Seq. ID Nos. 20 and 21 (hOP2) and Seq. ID Nos. 22 and 23 (mOP2.) The mature proteins are defined essentially by residues 264-402 (hOP2) and 261-399 (mOP2). The "pro" regions of the proteins, cleaved to yield the mature, morphogenically active proteins likely are defined essentially by residues 18-263 (hOP2) and residues 18-260 (mOP2). (Another cleavage site also occurs 21 residues upstream for both OP-2 proteins. ) "CBMP2" refers generically to the morphogenically active proteins expressed from a DNA sequence encoding the CBMP2 proteins, including allelic and species variants thereof, e.g., human CBMP2A ("CBMP2A(fx) ", Seq ID No. 9) or human CBMP2B DNA ("CBMP2B(fx) H , Seq. ID No. 10). The amino acid sequence for the full length proteins, referred to in the literature as BMP2A and BMP2B, or BMP2 and BMP4, appear in Wozney, et al. (1988) Science 242:1528- 1534. The pro domain for BMP2 (BMP2A) likely includes residues 25-248 or 25-282; the mature protein, residues 249-396 or 283-396. The pro domain for BMP4 (BMP2B) likely includes residues 25-256 or 25-292; the mature protein, residues 257-408 or 293-408. "DPP(fx)" refers to protein sequences encoded by the Drosophila DPP gene and defining the conserved seven cysteine skeleton (Seq. ID No. 11). The amino acid sequence for the full length protein appears in Padgett, et al (1987) Nature 325: 81-84. The pro domain likely extends from the signal peptide cleavage site to residue 456; the mature protein likely is defined by residues 457-588. "Vgl(fx)" refers to protein sequences encoded by the Xenopus Vgl gene and defining the conserved seven cysteine skeleton (Seq. ID No. 12). The amino acid sequence for the full length protein appears in Weeks (1987) Cell 51: 861-867. The prodomain likely extends from the signal peptide cleavage site to residue 246; the mature protein likely is defined by residues 247-360. "Vgr-l(fx)" refers to protein sequences encoded by the murine Vgr-1 gene and defining the conserved seven cysteine skeleton (Seq. ID No. 13). The amino acid sequence for the full length protein appears in Lyons, et al, (1989) PNAS 86: 4554-4558. The prodomain likely extends from the signal peptide cleavage site to residue 299; the mature protein likely is defined by residues 300-438. "GDF-l(fx)" refers to protein sequences encoded by the human GDF-1 gene and defining the conserved seven cysteine skeleton (Seq. ID No. 14). The cDNA and encoded amino sequence for the full length protein is provided in Seq. ID. No. 32. The prodomain likely extends from the signal peptide clavage site to residue 214; the mature protein likely is defined by residues 215-372. "60A" refers generically to the morphogenically active proteins expressed from part or all of a DNA sequence (from the Drosophila 60A gene) encoding the 60A proteins (see Seq. ID No. 24 wherein the cDNA and encoded amino acid sequence for the full length protein is provided). "60A(fx)" refers to the protein sequences defining the conserved seven cysteine skeleton (residues 354 to 455 of Seq. ID No. 24.) The prodomain likely extends from the signal peptide cleavage site to residue 324; the mature protein likely is defined by residues 325-455. "BMP3(fx)" refers to protein sequences encoded by the human BMP3 gene and defining the conserved seven cysteine skeleton (Seq. ID No. 26). The amino acid sequence for the full length protein appears in Wozney et al. (1988) Science 242: 1528-1534. The pro domain likely extends from the signal peptide cleavage site to residue 290; the mature protein likely is defined by residues 291-472. "BMP5(fx)" refers to protein sequences encoded by the human BMP5 gene and defining the conserved seven cysteine skeleton (Seq. ID No. 27). The amino acid sequence for the full length protein appears in Celeste, et al. (1991) PNAS 87: 9843-9847. The pro domain likely extends from the signal peptide cleavage site to residue 316; the mature protein likely is defined by residues 317-454. "BMP6(fx) refers to protein sequences encoded by the human BMP6 gene and defining the conserved seven cysteine skeleton (Seq. ID No. 28). The amino acid sequence for the full length protein appear sin Celeste, et al. (1990) PNAS 87: 9843-5847. The pro domain likely includes extends from the signal peptide cleavage site to residue 374; the mature sequence likely includes residues 375-513. The OP-2 proteins have an additional cysteine residue in this region (e.g., see residue 41 of Seq. ID Nos. 7 and 8), in addition to the conserved cysteine skeleton in common with the other proteins in this family. The GDF-1 protein has a four amino acid insert within the conserved skeleton (residues 44-47 of Seq. ID No. 14) but this insert likely does not interfere with the relationship of the cysteines in the folded structure. In addition, the CBMP2 proteins are missing one amino acid residue within the cysteine skeleton. The morphogens are inactive when reduced, but are active as oxidized homodimers and when oxidized in combination with other morphogens of this invention. Thus, as defined herein, a morphogen is a dimeric protein comprising a pair of polypeptide chains, wherein each polypeptide chain comprises at least the C-terminal six cysteine skeleton defined by residues 43-139 of Seq. ID No. 5, including functionally equivalent arrangements of these cysteines (e.g., amino acid insertions or deletions which alter the linear arrangement of the cysteines in the sequence but not their relationship in the folded structure), such that, when the polypeptide chains are folded, the dimeric protein species comprising the pair of polypeptide chains has the appropriate three-dimensional structure, including the appropriate intra- or inter-chain disulfide bonds such that the protein is capable of acting as a morphogen as defined herein. Specifically, the morphogens generally are capable of all of the following biological functions in a morphogenically permissive environment: stimulating proliferation of progenitor cells; stimulating the differentiation of progenitor cells; stimulating the proliferation of differentiated cells; and supporting the growth and maintenance of differentiated cells. In addition, it is also anticipated that these morphogens are capable of inducing redifferentiation of committed cells under appropriate environmental conditions. In one preferred aspect, the morphogens of this invention comprise one of two species of generic amino acid sequences: Generic Sequence 1 (Seq. ID No. 1) or Generic Sequence 2 (Seq. ID No. 2); where each Xaa indicates one of the 20 naturally-occurring L-isomer, α-amino acids or a derivative thereof. Generic Sequence 1 comprises the conserved six cysteine skeleton and Generic Sequence 2 comprises the conserved six cysteine skeleton plus the additional cysteine identified in OP-2 (see residue 36, Seq. ID No. 2). In another preferred aspect, these sequences further comprise the following additional sequence at their N- terminus: Cys Xaa Xaa Xaa Xaa (Seq. ID No. 15) 1 5 Preferred amino acid sequences within the foregoing generic sequences include: Generic Sequence 3 (Seq. ID No. 3), Generic Sequence 4 (Seq. ID No. 4), Generic Sequence 5 (Seq. ID No. 30) and Generic Sequence 6 (Seq. ID No. 31), listed below. These Generic Sequences accommodate the homologies shared among the various preferred members of this morphogen family identified in Table II, as well as the amino acid sequence variation among them. Specifically, Generic Sequences 3 and 4 are composite amino acid sequences of the following proteins presented in Table II and identified in Seq. ID Nos. 5-14: human OP-1 (hOP-1, Seq. ID Nos. 5 and 16-17), mouse OP-1 (mOP-1, Seq. ID Nos. 6 and 18-19), human and mouse OP-2 (Seq. ID Nos. 7, 8, and 20-22), CBMP2A (Seq. ID No. 9), CBMP2B (Seq. ID No. 10), DPP (from Drosophila, Seq. ID No. 11), Vgl, (from Xenopus, Seq. ID No. 12), Vgr-1 (from mouse, Seq. ID No. 13), and GDF-1 (from mouse, Seq. ID No. 14.) The generic sequences include both the amino acid identity shared by the sequences in Table II, as well as alternative residues for the variable positions within the sequence. Note that these generic sequences allow for an additional cysteine at position 41 or 46 in Generic Sequences 3 or 4, respectively, providing an appropriate cysteine skeleton where inter- or intramolecular disulfide bonds can form, and contain certain critical amino acids which influence the tertiary structure of the proteins. Generic Sequence 3 Leu Tyr Val Xaa Phe 1 5 Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa 10 Xaa Ala Pro Xaa Gly Xaa Xaa Ala 15 20 Xaa Tyr Cys Xaa Gly Xaa Cys Xaa 25 30 Xaa Pro Xaa Xaa Xaa Xaa Xaa 35 Xaa Xaa Xaa Asn His Ala Xaa Xaa 40 45 Xaa Xaa Leu Xaa Xaa Xaa Xaa Xaa 50 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys 55 60 Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa 65 Xaa Xaa Xaa Leu Xaa Xaa Xaa 70 75 Xaa Xaa Xaa Xaa Val Xaa Leu Xaa 80 Xaa Xaa Xaa Xaa Met Xaa Val Xaa 85 90 Xaa Cys Gly Cys Xaa 95 wherein each Xaa is independently selected from a group of one or more specified amino acids defined as follows: "Res." means "residue" and Xaa at res.4 = (Ser, Asp or Glu); Xaa at res.6 = (Arg, Gin, Ser or Lys); Xaa at res.7 = (Asp or Glu); Xaa at res.8 = (Leu or Val); Xaa at res.11 = (Gin, Leu, Asp, His or Asn); Xaa at res.12 = (Asp, Arg or Asn); Xaa at res.14 = (lie or Val); Xaa at res.15 = (lie or Val); Xaa at res.18 = (Glu, Gin, Leu, Lys, Pro or Arg); Xaa at res.20 = (Tyr or Phe); Xaa at res.21 = (Ala, Ser, Asp, Met, His, Leu or Gin); Xaa at res.23 = (Tyr, Asn or Phe); Xaa at res.26 = (Glu, His, Tyr, Asp or Gin); Xaa at res.28 = (Glu, Lys, Asp or Gin); Xaa at res.30 = (Ala, Ser, Pro or Gin); Xaa at res.31 = (Phe, Leu or Tyr); Xaa at res.33 = (Leu or Val); Xaa at res.34 = (Asn, Asp, Ala or Thr); Xaa at res.35 = (Ser, Asp, Glu, Leu or Ala); Xaa at res.36 = (Tyr, Cys, His, Ser or lie); Xaa at res.37 = (Met, Phe, Gly or Leu); Xaa at res.38 = (Asn or Ser); Xaa at res.39 = (Ala, Ser or Gly); Xaa at res.40 = (Thr, Leu or Ser); Xaa at res.44 = (lie or Val); Xaa at res.45 = (Val or Leu); Xaa at res.46 = (Gin or Arg); Xaa at res.47 = (Thr, Ala or Ser); Xaa at res.49 = (Val or Met); Xaa at res.50 = (His or Asn); Xaa at res.51 = (Phe, Leu, Asn, Ser, Ala or Val); Xaa at res.52 = (lie. Met, Asn, Ala or Val); Xaa at res.53 = (Asn, Lys, Ala or Glu); Xaa at res.54 = (Pro or Ser); Xaa at res.55 = (Glu, Asp, Asn, or Gly); Xaa at res.56 = (Thr, Ala, Val, Lys, Asp, Tyr, Ser or Ala); Xaa at res.57 = (Val, Ala or lie); Xaa at res.58 = (Pro or Asp); Xaa at res.59 = (Lys or Leu); Xaa at res.60 = (Pro or Ala); Xaa at res.63 = (Ala or Val); Xaa at res.65 = (Thr or Ala); Xaa at res.66 = (Gin, Lys, Arg or Glu); Xaa at res.67 = (Leu, Met or Val); Xaa at res.68 = (Asn, Ser or Asp); Xaa at res.69 = (Ala, Pro or Ser); Xaa at res.70 = (lie, Thr or Val); Xaa at res.71 = (Ser or Ala); Xaa at res.72 = (Val or Met); Xaa at res.74 = (Tyr or Phe); Xaa at res.75 = (Phe, Tyr or Leu); Xaa at res.76 = (Asp or Asn); Xaa at res.77 = (Asp, Glu, Asn or Ser); Xaa at res.78 = (Ser, Gin, Asn or Tyr); Xaa at res.79 = (Ser, Asn, Asp or Glu); Xaa at res.80 = (Asn, Thr or Lys); Xaa at res.82 = (lie or Val); Xaa at res.84 = (Lys or Arg); Xaa at res.85 = (Lys, Asn, Gin or His); Xaa at res.86 = (Tyr or His); Xaa at res.87 = (Arg, Gin or Glu); Xaa at res.88 = (Asn, Glu or Asp); Xaa at res.90 = (Val, Thr or Ala); Xaa at res.92 = (Arg, Lys, Val, Asp or Glu); Xaa at res.93 * (Ala, Gly or Glu); and Xaa at res.97 = (His or Arg); Generic Sequence 4 Cys Xaa Xaa Xaa Xaa Leu Tyr Val Xaa Phe 1 5 10 Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa 15 Xaa Ala Pro Xaa Gly Xaa Xaa Ala 20 25 Xaa Tyr Cys Xaa Gly Xaa Cys Xaa 30 35 Xaa Pro Xaa Xaa Xaa Xaa Xaa 40 Xaa Xaa Xaa Asn His Ala Xaa Xaa 45 50 Xaa Xaa Leu Xaa Xaa Xaa Xaa Xaa 55 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys 60 65 Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa 70 Xaa Xaa Xaa Leu Xaa Xaa Xaa 75 80 Xaa Xaa Xaa Xaa Val Xaa Leu Xaa 85 Xaa Xaa Xaa Xaa Met Xaa Val Xaa 90 95 Xaa Cys Gly Cys Xaa 100 wherein each Xaa is independently selected from a group of one or more specified amino acids as defined by the following: "Res." means "residue" and Xaa at res.2 = (Lys or Arg); Xaa at res.3 = (Lys or Arg); Xaa at res.4 = (His or Arg); Xaa at res.5 = (Glu, Ser, His, Gly, Arg or Pro); Xaa at res.9 = (Ser, Asp or Glu); Xaa at res.11 = (Arg, Gin, Ser or Lys); Xaa at res.12 = (Asp or Glu); Xaa at res.13 = (Leu or Val); Xaa at res.16 = (Gin, Leu, Asp, His or Asn); Xaa at res.17 = (Asp, Arg, or Asn); Xaa at res.19 = (lie or Val); Xaa at res.20 = (lie or Val); Xaa at res.23 = (Glu, Gin, Leu, Lys, Pro or Arg); Xaa at res.25 = (Tyr or Phe); Xaa at res.26 = (Ala, Ser, Asp, Met, His, Leu, or Gin); Xaa at res.28 = (Tyr, Asn or Phe); Xaa at res.31 = (Glu, His, Tyr, Asp or Gin); Xaa at res.33 = Glu, Lys, Asp or Gin); Xaa at res.35 = (Ala, Ser or Pro); Xaa at res.36 = (Phe, Leu or Tyr); Xaa at res.38 = (Leu or Val); Xaa at res.39 = (Asn, Asp, Ala or Thr); Xaa at res.40 = (Ser, Asp, Glu, Leu or Ala); Xaa at res.41 = (Tyr, Cys, His, Ser or lie); Xaa at res.42 = (Met, Phe, Gly or Leu); Xaa at res.44 = (Ala, Ser or Gly); Xaa at res.45 = (Thr, Leu or Ser); Xaa at res.49 = (lie or Val); Xaa at res.50 - (Val or Leu); Xaa at res.51 - (Gin or Arg); Xaa at res.52 = (Thr, Ala or Ser); Xaa at res.54 = (Val or Met); Xaa at res.55 = (His or Asn); Xaa at res.56 = (Phe, Leu, Asn, Ser, Ala or Val); Xaa at res.57 = (lie. Met, Asn, Ala or Val); Xaa at res.58 = (Asn, Lys, Ala or Glu); Xaa at res.59 = (Pro or Ser); Xaa at res.60 = (Glu, Asp, or Gly); Xaa at res.61 «= (Thr, Ala, Val, Lys, Asp, Tyr, Ser or Ala); Xaa at res.62 = (Val, Ala or lie); Xaa at res.63 = (Pro or Asp); Xaa at res.64 = (Lys or Leu); Xaa at res.65 = (Pro or Ala); Xaa at res.68 = (Ala or Val); Xaa at res.70 = (Thr or Ala); Xaa at res.71 = (Gin, Lys, Arg or Glu); Xaa at res.72 = (Leu, Met or Val); Xaa at res.73 = (Asn, Ser or Asp); Xaa at res.74 = (Ala, Pro or Ser); Xaa at res.75 = (lie, Thr or Val); Xaa at res.76 = (Ser or Ala); Xaa at res.77 = (Val or Met); Xaa at res.79 = (Tyr or Phe); Xaa at res.80 = (Phe, Tyr or Leu); Xaa at res.81 = (Asp or Asn); Xaa at res.82 = (Asp, Glu, Asn or Ser); Xaa at res.83 = (Seir, Gin, Asn or Tyr); Xaa at res.84 = (Ser, Asn, Asp or Glu); Xaa at res.85 = (Asn, Thr or Lys); Xaa at res.87 = (lie or Val); Xaa at res.89 = (Lys or Arg); Xaa at res.90 = (Lys, Asn, Gin or His); Xaa at res.91 = (Tyr or His); Xaa at res.92 = (Arg, Gin or Glu); Xaa at res.93 = (Asn, Glu or Asp); Xaa at res.95 = (Val, Thr or Ala); Xaa at res.97 = (Arg, Lys, Val, Asp or Glu); Xaa at res.98 = (Ala, Gly or Glu); and Xaa at res.102 = (His or Arg). Similarly, Generic Sequence 5 (Seq. ID No. 30) and Generic Sequence 6 (Seq. ID No. 31) accommodate the homologies shared among all the morphogen protein family members identified in Table II. Specifically, Generic Sequences 5 and 6 are composite amino acid sequences of human OP-1 (hOP-1, Seq. ID Nos. 5 and 16- 17), mouse OP-1 (mOP-1, Seq. ID Nos. 6 and 18-19), human and mouse OP-2 (Seq. ID Nos. 7, 8, and 20-22), CBMP2A (Seq. ID No. 9), CBMP2B (Seq. ID No. 10), DPP (from Drosophila, Seq. ID No. 11), Vgl, (from Xenopus, Seq. ID No. 12), Vgr-1 (from mouse, Seq. ID No. 13), and GDF-1 (from mouse, Seq. ID No. 14), human BMP3 (Seq. ID No. 26), human BMP5 (Seq. ID No. 27), human BMP6 (Seq. ID No. 28) and 60(A) (from Drosophila, Seq. ID Nos. 24-25). The generic sequences include both the amino acid identity shared by these sequences in the C-terminal domain, defined by the six and seven cysteine skeltons (Generic Sequences 5 and 6, respectively), as well as alternative residues for the variable positions within the sequence. As for Generic Sequences 3 and 4, Generic Sequences 5 and 6 allow for an additional cysteine at position 41 (Generic Sequence 5) or position 46 (Generic Sequence 6), providing an appropriate cysteine skeleton where inter- or intramolecular disulfide bonds can form, and containing certain critical amino acids which influence the tertiary structure of the proteins. Generic Sequence 5 Leu Xaa Xaa Xaa Phe 1 5 Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa 10 Xaa Xaa Pro Xaa Xaa Xaa Xaa Ala 15 20 Xaa Tyr Cys Xaa Gly Xaa Cys Xaa 25 30 Xaa Pro Xaa Xaa Xaa Xaa Xaa 35 Xaa Xaa Xaa Asn His Ala Xaa Xaa 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys 55 60 Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa 65 Xaa Xaa Xaa Leu Xaa Xaa Xaa 70 75 Xaa Xaa Xaa Xaa Val Xaa Leu Xaa 80 Xaa Xaa Xaa Xaa Met Xaa Val Xaa 85 90 Xaa Cys Xaa Cys Xaa 95 wherein each Xaa is independently selected from a group of one or more specified amino acids defined as follows: "Res." means "residue" and Xaa at res.2 •= (Tyr or Lys); Xaa at res.3 = Val or lie); Xaa at res.4 = (Ser, Asp or Glu); Xaa at res.6 = (Arg, Gin, Ser, Lys or Ala); Xaa at res.7 = (Asp, Glu or Lys); Xaa at res.8 = (Leu, Val or lie); Xaa at res.11 = (Gin, Leu, Asp, His, Asn or Ser); Xaa at res.12 = (Asp, Arg, Asn or Glu); Xaa at res.14 = (lie or Val); Xaa at res.15 = (lie or Val); Xaa at res.16 (Ala or Ser); Xaa at res.18 = (Glu, Gin, Leu, Lys, Pro or Arg); Xaa at res.19 = (Gly or Ser); Xaa at res.20 - (Tyr or Phe); Xaa at res.21 = (Ala, Ser, Asp, Met, His, Gin, Leu or Gly); Xaa at res.23 = (Tyr, Asn or Phe); Xaa at res.26 = (Glu, His, Tyr, Asp, Gin or Ser); Xaa at res.28 = (Glu, Lys, Asp, Gin or Ala); Xaa at res.30 - (Ala, Ser, Pro, Gin or Asn); Xaa at res.31 « (Phe, Leu or Tyr); Xaa at res.33 = (Leu, Val or Met); Xaa at res.34 = (Asn, Asp, Ala, Thr or Pro); Xaa at res.35 = (Ser, Asp, Glu, Leu, Ala or Lys); Xaa at res.36 = (Tyr, Cys, His, Ser or lie); Xaa at res.37 = (Met, Phe, Gly or Leu); Xaa at res.38 = (Asn, Ser or Lys); Xaa at res.39 = (Ala, Ser, Gly or Pro); Xaa at res.40 = (Thr, Leu or Ser); Xaa at res.44 = (lie, Val or Thr); Xaa at res.45 = (Val, Leu or lie); Xaa at res.46 = (Gin or Arg); Xaa at res.47 = (Thr, Ala or Ser); Xaa at res.48 = (Leu or lie); Xaa at res.49 = (Val or Met); Xaa at res.50 = (His, Asn or Arg); Xaa at res.51 = (Phe, Leu, Asn, Ser, Ala or Val); Xaa at res.52 = (lie. Met, Asn, Ala, Val or Leu); Xaa at res.53 = (Asn, Lys, Ala, Glu, Gly or Phe); Xaa at res.54 = (Pro, Ser or Val); Xaa at res.55 = (Glu/ Asp, Asn, Gly, Val or Lys); Xaa at res.56 = (Thr, Ala, Val, Lys, Asp, Tyr, Ser, Ala, Pro or His); Xaa at res.57 = (Val, Ala or lie); Xaa at res.58 = (Pro or Asp); Xaa at res.59 = (Lys, Leu or Glu); Xaa at res.60 = (Pro or Ala); Xaa at res.63 = (Ala or Val); Xaa at res.65 = (Thr, Ala or Glu); Xaa at res.66 = (Gin, Lys, Arg or Glu); Xaa at res.67 = (Leu, Met or Val); Xaa at res.68 = (Asn, Ser, Asp or Gly); Xaa at res.69 = (Ala, Pro or Ser); Xaa at res.70 = (lie, Thr, Val or Leu); Xaa at res.71 = (Ser, Ala or Pro); Xaa at res.72 = (Val, Met or lie); Xaa at res.74 = (Tyr or Phe); Xaa at res.75 = (Phe, Tyr, Leu or His); Xaa at res.76 = (Asp, Asn or Leu); Xaa at res.77 - (Asp, Glu, Asn or Ser); Xaa at res.78 = (Ser, Gin, Asn, Tyr or Asp); Xaa at res.79 = (Ser, Asn, Asp, Glu or Lys); Xaa at res.80 = (Asn, Thr or Lys); Xaa at res.82 = (lie, Val or Asn); Xaa at res.84 = (Lys or Arg); Xaa at res.85 = (Lys, Asn, Gin, His or Val); Xaa at res.86 = (Tyr or His); Xaa at res.87 - (Arg, Gin, Glu or Pro); Xaa at res.88 = (Asn, Glu or Asp); Xaa at res.90 = (Val, Thr, Ala or lie); Xaa at res.92 = (Arg, Lys, Val, Asp or Glu); Xaa at res.93 = (Ala, Gly, Glu or Ser); Xaa at res.95 = (Gly or Ala) and Xaa at res.97 = (His or Arg). Generic Sequence 6 Cys Xaa Xaa Xaa Xaa Leu Xaa Xaa Xaa Phe 1 5 10 Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa 15 Xaa Xaa Pro Xaa Xaa Xaa Xaa Ala 20 25 Xaa Tyr Cys Xaa Gly Xaa Cys Xaa 30 35 Xaa Pro Xaa Xaa Xaa Xaa Xaa 40 Xaa Xaa Xaa Asn His Ala Xaa Xaa 45 50 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 55 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys 60 65 Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa 70 Xaa Xaa Xaa Leu Xaa Xaa Xaa 75 80 Xaa Xaa Xaa Xaa Val Xaa Leu Xaa 85 Xaa Xaa Xaa Xaa Met Xaa Val Xaa 90 95 Xaa Cys Xaa Cys Xaa 100 wherein each Xaa is independently selected from a group of one or more specified amino acids as defined by the following: "Res." means "residue" and Xaa at res.2 = (Lys, Arg, Ala or Gin); Xaa at res.3 = (Lys, Arg or Met); Xaa at res.4 = (His, Arg or Gin); Xaa at res.5 = (Glu, Ser, His, Gly, Arg, Pro, Thr, or Tyr); Xaa at - Sδ - res.? = (Tyr or Lys); Xaa at res.8 = (Val or lie); Xaa at res.9 = (Ser, Asp or Glu); Xaa at res.11 = (Arg, Gin, Ser, Lys or Ala); Xaa at res.12 = (Asp, Glu, or Lys); Xaa at res.13 = (Leu, Val or lie); Xaa at res.16 = (Gin, Leu, Asp, His, Asn or Ser); Xaa at res.17 = (Asp, Arg, Asn or Glu); Xaa at res.19 = (lie or Val); Xaa at res.20 = (lie or Val); Xaa at res.21 = (Ala or Ser); Xaa at res.23 = (Glu, Gin, Leu, Lys, Pro or Arg); Xaa at res.24 = (Gly or Ser); Xaa at res.25 = (Tyr or Phe); Xaa at res.26 = (Ala, Ser, Asp, Met, His, Gin, Leu, or Gly); Xaa at res.28 •= (Tyr, Asn or Phe); Xaa at res.31 •= (Glu, His, Tyr, Asp, Gin or Ser); Xaa at res.33 = Glu, Lys, Asp, Gin or Ala); Xaa at res.35 = (Ala, Ser, Pro, Gin or Asn); Xaa at res.36 = (Phe, Leu or Tyr); Xaa at res.38 = (Leu, Val or Met); Xaa at res.39 = (Asn, Asp, Ala, Thr or Pro); Xaa at res.40 = (Ser, Asp, Glu, Leu, Ala or Lys); Xaa at res.41 = (Tyr, Cys, His, Ser or lie); Xaa at res.42 = (Met, Phe, Gly or Leu); Xaa at res. 3 = (Asn, Ser or Lys); Xaa at res.44 = (Ala, Ser, Gly or Pro); Xaa at res.45 = (Thr, Leu or Ser); Xaa at res.49 = (lie, Val or Thr); Xaa at res.50 = (Val, Leu or lie); Xaa at res.51 = (Gin or Arg); Xaa at res.52 = (Thr, Ala or Ser); Xaa at res.53 - (Leu or lie); Xaa at res.54 = (Val or Met); Xaa at res.55 = (His, Asn or Arg); Xaa at res.56 = (Phe, Leu, Asn, Ser, Ala or Val); Xaa at res.57 = (lie. Met, Asn, Ala, Val or Leu); Xaa at res.58 = (Asn, Lys, Ala, Glu, Gly or Phe); Xaa at res.59 = (Pro, Ser or Val); Xaa at res.60 = (Glu, Asp, Gly, Val or Lys); Xaa at res.61 = (Thr, Ala, Val, Lys, Asp, Tyr, Ser, Ala, Pro or His); Xaa at res.62 = (Val, Ala or lie); Xaa at res.63 == (Pro or Asp); Xaa at res.64 = (Lys, Leu or Glu); Xaa at es.65 = (Pro or Ala); Xaa at res.68 = (Ala or Val); Xaa at res.70 = (Thr, Ala or Glu); Xaa at res.71 = (Gin, Lys, Arg or Glu); Xaa at res.72 = (Leu, Met or Val); Xaa at res.73 = (Asn, Ser, Asp or Gly); Xaa at res.74 = (Ala, Pro or Ser); Xaa at res.75 = (He, Thr, Val or Leu); Xaa at res.76 = (Ser, Ala or Pro); Xaa at res.77 = (Val, Met or He); Xaa at res.79 = (Tyr or Phe); Xaa at res.80 = (Phe, Tyr, Leu or His); Xaa at res.81 = (Asp, Asn or Leu); Xaa at res.82 = (Asp, Glu, Asn or Ser); Xaa at res.83 = (Ser, Gin, Asn, Tyr Or Asp); Xaa at res.84 = (Ser, Asn, Asp, Glu or Lys); Xaa at res.85 = (Asn, Thr or Lys); Xaa at res.87 = (He, Val or Asn); Xaa at res.89 = (Lys or Arg); Xaa at res.90 = (Lys, Asn, Gin, His or Val); Xaa at res.91 = (Tyr or His); Xaa at res.92 •= (Arg, Gin, Glu or Pro); Xaa at res.93 ~ = (Asn, Glu or Asp); Xaa at res.95 - (Val, Thr, Ala or He); Xaa at res.97 = (Arg, Lys, Val, Asp or Glu); Xaa at res.98 = (Ala, Gly, Glu or Ser); Xaa at res.100 = (Gly or Ala); and Xaa at res.102 = (His or Arg) . Particularly useful sequences for use as morphogens in this invention include the C-terminal domains, e.g., the C-terminal 96-102 amino acid residues of Vgl, Vgr-1, DPP, OP-1, OP-2, CBMP-2A, CBMP-2B, GDF-1 (see Table II, below, and Seq. ID Nos. 5-14), as well as proteins comprising the C-terminal domains of 60A, BMP3, BMP5 and BMP6 (see Seq. ID Nos. 24-28), all of which include at least the conserved six or seven cysteine skeleton. In addition, biosynthetic constructs designed from the generic sequences, such as COP-1, 3-5, 7, 16, disclosed in U.S. Pat. No. 5,011,691, also are useful. Other sequences include the inhibins/activin proteins (see, for example, U.S. Pat. Nos. 4,968,590 and 5,011,691). Accordingly, other useful proteins are those exhibiting morphogenic activity and having amino acid sequences sharing at least 70% amino acid sequence homology or "similarity", and preferably 80% homology or similarity with any of the sequences above. These are anticipated to include allelic variants, species variants and other sequence variants (e.g., "muteins" or "mutant proteins"), whether naturally occurring or biosynthetically produced, as well as novel members of this morphogenic family of proteins. As used herein, "amino acid sequence homology" is understood to mean amino acid sequence similarity, and homologous sequences share identical or similar amino acids, where similar amino acids are conserved amino acids as defined by Dayoff et al.. Atlas of Protein Sequence and Structure; vol.5, Suppl.3, pp.345-362 (M.O. Dayoff, ed., Nat'l BioMed. Research Fdn. , Washington D.C. 1978.) Thus, a candidate sequence sharing 70% amino acid homology with a reference sequence requires that, following alignment of the candidate sequence with the reference sequence, 70% of the amino acids in the candidate sequence are identical to the corresponding amino acid in the reference sequence, or constitute a conserved amino acid change thereto. "Amino acid sequence identity" is understood to require identical amino acids between two aligned sequences. Thus, a candidate sequence sharing 60% amino acid identity with a reference sequence requires that, following alignment of the candidate sequence with the reference sequence, 60% of the amino acids in the candidate sequence are identical to the corresponding amino acid in the reference sequence. As used herein, all homologies and identities calculated use OP-1 as the reference sequence. Also as used herein, sequences are aligned for homology and identity calculations using the method of Needleman et al. (1970) J.Mol. Biol. 48:443-453 and identities calculated by the Align program (DNAstar, Inc.) In all cases, internal gaps and amino acid insertions in the candidate sequence as aligned are ignored when making the homology/identity calculation. The currently most preferred protein sequences useful as morphogens in this invention include those having greater than 60% identity, preferably greater than 65% identity, with the amino acid sequence defining the conserved six cysteine skeleton of hOPl (e.g., residues 43-139 of Seq. ID No. 5). These most preferred sequences include both allelic and species variants of the OP-1 and OP-2 proteins, including the Drosophila 60A protein. Accordingly, in another preferred aspect of the invention, useful morphogens include active proteins comprising species of polypeptide chains having the generic amino acid sequence herein referred to as "OPX", which accommodates the homologies between the various identified species of 0P1 and OP2 (Seq. ID No. 29). In still another preferred aspect of the invention, useful morphogens include active proteins comprising polypeptide chains encoded by nucleic acids which hybridize to DNA or RNA sequences encoding the C- terminal sequence defining the consumed cysteine domain, e.g., nucleotides 1036-1341 and nucleotides 1390-1695 of Seq. Id. Nos. 16 and 20, respectively, of OP1 or OP2 under stringent hybridization conditions. As used herein, stringent hybridization conditions are defined as hybridization in 40% formamide, 5 X SSPE, 5 X Denhardt's Solution, and 0.1% SDS at 37°C overnight, and wshing in 0.1 X SSPE, 0.1% SDS at 50°C. The morphogens useful in the methods, composition and devices of this invention include proteins comprising any of the polypeptide chains described above, whether isolated from naturally-occurring sources, or produced by recombinant DNA or other synthetic techniques, and includes allelic and species variants of these proteins, naturally-occurring or biosynthetic mutants thereof, as well as various truncated and fusion constructs. Deletion or addition mutants also are envisioned to be active, including those which may alter the conserved C-terminal cysteine skeleton, provided that the alteration does not functionally disrupt the relationship of these cysteines in the folded structure. Accordingly, such active forms are considered the equivalent of the specifically described constructs disclosed herein. The proteins may include forms having varying glycosylation patterns, varying N-termini, a family of related proteins having regions of amino acid sequence homology, and active truncated or mutated forms of native or biosynthetic proteins, produced by expression of recombinant DNA in host cells. The morphogenic proteins can be expressed from intact or truncated cDNA or from synthetic DNAs in procaryotic or eucaryotic host cells, and purified, cleaved, refolded, and dimerized to form morphogenically active compositions. Currently preferred host cells include 15^ coli or mammalian cells, such as CHO, COS or BSC cells. A detailed description of the morphogens useful in the methods. compositions and devices of this invention is disclosed in copending US patent application Serial Nos. 752,764, filed August 30, 1991, and 667,274, filed March 11, 1991, the disclosure of which are incorporated herein by reference. Thus, in view of this disclosure, skilled genetic engineers can isolate genes from cDNA or genomic libraries of various different species which encode appropriate amino acid sequences, or construct DNAs from oligonucleotides, and then can express them in various types of host cells, including both procaryotes and eucaryotes, to produce large quantities of active proteins capable of maintaining neural pathways in a mammal, including enhancing the survival of neurons at risk of dying and stimulating nerve regeneration and repair in a variety of mammals, including humans. The foregoing and other objects, features and advantages of the present invention will be made more apparent from the following detailed description of the invention. Brief Description of the Drawings: The foregoing and other objects and features of this invention, as well as the invention itself, may be more fully understood from the following description, when read together with the accompanying drawings, in which: Fig. 1(A and B) are photomicrographs illustrating the ability of morphogen (OP-1) to induce transformed neuroblastoma x glioma cells (1A) to redifferentiate to a morphology characteristic of untransformed neurons (IB); Fig. 2A is a dose response curve for the induction of the 180 kDa and 140 kDa N-CAM isoforms in morphogen- treated NG108-15 cells; Fig. 2B is a photomicrograph of a Western blot of whole cell extracts from morphogen-treated NG108-15 cells with an N-CAM-specific antibody; and Fig. 3 is a plot of the mean number of cell aggregates counted in 20 randomly selected fields as a function of morphogen concentration. Fig. 4 is a photomicrograph of an immunoblot demonstrating the presence of OP-1 in human serum. Detailed Description of the Invention It now has been discovered that the proteins described herein are effective agents for enhancing the survival of neurons, particularly neurons at risk of dying, and for maintaining neural pathways in a mammal. As described herein, these proteins ("morphogens") are capable of enhancing survival of non-mitotic neurons, stimulating neuronal CAM expression, maintaining the phenotypic expression of differentiated neurons, inducing the redifferentiation of transformed cells of neural origin, and stimulating axonal growth over breaks in neural processes, particularly large gaps in distal axons. The proteins also are capable of providing a neuroprotective effect to alleviate the tissue destructive effects associated with immunologically-related nerve tissue damage. Finally, the proteins may be used as part of a method for monitoring the viability of nerve tissue in a mammal. Provided below are detailed descriptions of suitable morphogens useful in the methods, compositions and devices of this invention, as well as methods for their administration and application, and numerous, nonlimiting examples which 1) illustrate the suitability of the morphogens and morphogen-stimulating agents described herein as therapeutic agents for maintaining nerual pathways in a mammal and enhancing survival of neuronal cells at risk of dying; and 2) provide assays with which to test candidate morphogens and morphogen-stimulating agents for their efficacy. I. Useful Morphogens As defined herein a protein is morphogenic if it is capable of inducing the developmental cascade of cellular and molecular events that culminate in the formation of new, organ-specific tissue and comprises at least the conserved C-terminal six cysteine skeleton or its functional equivalent (see supra). Specifically, the morphogens generally are capable of all of the following biological functions in a morphogenically permissive environment: stimulating proliferation of progenitor cells; stimulating the differentiation of progenitor cells; stimulating the proliferation of differentiated cells; and supporting the growth and maintenance of differentiated cells. Details of how the morphogens useful in the method of this invention first were identified, as well as a description on how to make, use and test them for morphogenic activity are disclosed in international application US92/01968 (W092/15323) , the disclosure of which is hereby incorporated by reference. As disclosed therein, the morphogens may be purified from naturally-sourced material or recombinantly produced from procaryotic or eucaryotic host cells, using the genetic sequences disclosed therein. Alternatively, novel morphogenic sequences may be identified following the procedures disclosed therein. Particularly useful proteins include those which comprise the naturally derived sequences disclosed in Table II. Other useful sequences include biosynthetic constructs such as those disclosed in U.S. Pat. 5,011,691, the disclosure of which is incorporated herein by reference (e.g., COP-1, COP-3, COP-4, COP-5, COP-7, and COP-16). Accordingly, the morphogens useful in the methods and compositions of this invention also may be described by morphogenically active proteins having amino acid sequences sharing 70% or, preferably, 80% homology (similarity) with any of the sequences described above, where "homology" is as defined herein above. The morphogens useful in the method of this invention also can be described by any of the 6 generic sequences described herein (Generic Sequences 1, 2, 3, 4, 5 and 6). Generic sequences 1 and 2 also may include, at their N-terminus, the sequence Cys Xaa Xaa Xaa Xaa (Seq. ID No. 15) 1 5 Table II, set forth below, compares the amino acid sequences of the active regions of native proteins that have been identified as morphogens, including human OP-1 (hOP-1, Seq. ID Nos. 5 and 16-17), mouse OP-1 (mOP-1, Seq. ID Nos. 6 and 18-19), human and mouse OP-2 (Seq. ID Nos. 7, 8, and 20-23), CBMP2A (Seq. ID No. 9), CBMP2B (Seq. ID No. 10), BMP3 (Seq. ID No. 26), DPP (from Drosophila, Seq. ID No. 11), Vgl, (from Xenopus, Seq. ID No. 12), Vgr-1 (from mouse, Seq. ID No. 13), GDF-1 (from mouse, Seq. ID Nos. 14, 32 and 33), 60A protein (from Drosophila, Seq. ID Nos. 24 and 25), BMP5 (Seq. ID No. 27) and BMP6 (Seq. ID No. 28). The sequences are aligned essentially following the method of Needleman et al. (1970) J. Mol. Biol., A 8_:443-453, calculated using the Align Program ( DNAstar, Inc . ) In the table , three dots indicates that the amino acid in that position is the same as the amino acid in hOP-1. Three dashes indicates that no amino acid is present in that position, and are included for purposes of illustrating homologies . For example, amino acid residue 60 of CBMP-2A and CBMP-2B is "missing" . Of course, both these amino acid sequences in this region comprise Asn-Ser ( residues 58 , 59 ) , with CBMP-2A then comprising Lys and He , whereas CBMP-2B comprises Ser and He . TABLE II hOP-l Cys Lys Lys His Glu Leu Tyr Val m0P-l h0P-2 m0P-2 DPP Vgl Vgr-1 CBMP-2A CBMP-2B BMP3 Lys GDF-1 60A BMP5 BMP6 Arg hOP-l Ser Phe Arg Asp Leu Gly Trp Gin Asp mOP-l h0P-2 Gin Leu 10 15 He Ala Pro Glu Gly Tyr Ala 20 25 hOP-l Ala Tyr Tyr Cys Glu Gly Glu Cys Ala mOP-l hOP-2 • • • • • • • • • Ser mOP-2 DPP His Lys Pro hOP-l Phe Pro mOP-l h0P-2 m0P-2 DPP Vgl Tyr Vgr-1 CBMP-2A CBMP-2B GDF-1 Leu BMP3 60A BMP5 BMP6 hOP-l Thr Asn His Ala He Val Gin Thr Leu mOP-l h0P-2 Leu Ser m0P-2 Leu Ser DPP Val Vgl Ser Leu Vgr-1 CBMP-2A He 45 50 Lys Pro Cys Cys Ala Pro Thr Gin Leu 65 70 75 80 GDF-1 ... Asn ... Asp Val Arg 60A Leu Asn Asp Glu Asn BMP5 BMP6 Asn 85 90 95 Cys Gly Cys His Arg Arg • • • Arg Arg Ala Arg Arg 100 **Between residues 56 and 57 of BMP3 is a Val residue; between residues 43 and 44 of GDF-1 lies the amino acid sequence Gly-Gly-Pro-Pro. As is apparent from the foregoing amino acid sequence comparisons, significant amino acid changes can be made within the generic sequences while retaining the morphogenic activity. For example, while the GDF-1 protein sequence depicted in Table II shares only about 50% amino acid identity with the hOPl sequence described therein, the GDF-1 sequence shares greater than 70% amino acid sequence homology (or "similarity") with the hOPl sequence, where "homology" or "similarity" includes allowed conservative amino acid changes within the sequence as defined by Dayoff, et al.. Atlas of Protein Sequence and Structure vol.5, supp.3, pp.345-362, (M.O. Dayoff, ed., Nat'l BioMed. Res. Fd'n, Washington D.C. 1979.) The currently most preferred protein sequences useful as morphogens in this invention include those having greater than 60% identity, preferably greater than 65% identity, with the amino acid sequence defining the conserved six cysteine skeleton of hOPl (e.g., residues 43-139 of Seq. ID No. 5). These most preferred sequences include both allelic and species variants of the OP-1 and OP-2 proteins, including the Drosophila 60A protein. Accordingly, in still another preferred aspect, the invention includes morphogens comprising species of polypeptide chains having the generic amino acid sequence referred to herein as "OPX", which defines the seven cysteine skeleton and accommodates the identities between the various identified mouse and human OP1 and OP2 proteins. OPX is presented in Seq. ID No. 29. As described therein, each Xaa at a given position independently is selected from the residues occurring at the corresponding position in the C-terminal sequence of mouse or human OP1 or OP2 (see Seq. ID Nos. 5-8 and/or Seq. ID Nos. 16-23). II. Formulations and Methods for Administering Therapeutic Agents The morphogens may be provided to an individual by any suitable means, preferably directly (e.g., locally, as by injection to a nerve tissue locus) or systemically (e.g., parenterally or orally). Where the morphogen is to be provided parenterally, such as by intravenous, subcutaneous, intramuscular, intraorbital, ophthalmic, intraventricular, intracranial, intracapsular, intraspinal, intracisternal, intraperitoneal, buccal, rectal, vaginal, intranasal or by aerosol administration, the morphogen preferably comprises part of an aqueous solution. The solution is physiologically acceptable so that in addition to delivery of the desired morphogen to the patient, the solution does not otherwise adversely affect the patient's electrolyte and volume balance. The aqueous medium for the morphogen thus may comprise normal physiologic saline (9.85% NaCl, 0.15M), pH 7-7.4. The aqueous solution containing the morphogen can be made, for example, by dissolving the protein in 50% ethanol containing acetonitrile in 0.1% trifluoroacetic acid (TFA) or 0.1% HCl, or equivalent solvents. One volume of the resultant solution then is added, for example, to ten volumes of phosphate buffered saline (PBS), which further may include 0.1-0.2% human serum albumin (HSA). The resultant solution preferably is vortexed extensively. If desired, a given morphogen may be made more soluble by association with a suitable molecule. For example, association of the mature dimer with the pro domain of the morphogen increases solubility of the protein significantly (see Section II.1, below). In fact, the endogenous protein is thought to be transported in this form. Another molecule capable of enhancing solubility and particularly useful for oral administrations, is casein. For example, addition of 0.2% casein increases solubility of the mature active form of OP-1 by 80%. Other components found in milk and/or various serum proteins also may be useful. Useful solutions for parenteral administration may be prepared by any of the methods well known in the pharmaceutical art, described, for example, in Remington's Pharmaceutical Sciences (Gennaro, A., ed. ) , Mack Pub., 1990. Formulations may include, for example, polyalkylene glycols such as polyethylene glycol, oils of vegetable origin, hydrogenated naphthalenes, and the like. Formulations for direct administration, in particular, may include glycerol and other compositions of high viscosity. Biocompatible, preferably bioresorbable, polymers, including, for example, hyaluronic acid, collagen, polybutyrate, tricalcium phosphate, lactide and lactide/glycolide copolymers, may be useful excipients to control the release of the morphogen in vivo. Other potentially useful parenteral delivery systems for these morphogens include ethylene-vinyl acetate copolymer particles. osmotic pumps, implantable infusion systems, and liposomes. Formulations for inhalation administration contain as excipients, for example, lactose, or may be aqueous solutions containing, for example, polyoxyethylene-9-lauryl ether, glycocholate and deoxycholate, or oily solutions for administration in the form of nasal drops, or as a gel to be applied intranasally. Formulations for parenteral administration may also include glycocholate for buccal administration, methoxysalicylate for rectal administration, or cutric acid for vaginal administration. Alternatively, the morphogens described herein may be administered orally. Oral administration of proteins as therapeutics generally is not practiced as most proteins are readily degraded by digestive enzymes and acids in the mammalian digestive system before they can be absorbed into the bloodstream. However, the morphogens described herein typically are acid stable and protease-resistant (see, for example, U.S. Pat.No. 4,968,590.) In addition, at least one morphogen, OP-1, has been identified in mammary gland extract, colostrum and 57-day milk. Moreover, the OP-1 purified from mammary gland extract is morphogenically active. Specifically, this protein induces endochondral bone formation in mammals when implanted subcutaneously in association with a suitable matrix material, using a standard in vivo bone assay, such as is disclosed in U.S. Pat.No. 4,968,590. Moreover, the morphogen also is detected in the bloodstream (see Example 9, below). Finally, soluble form morphogen, e.g., mature morphogen associated with the pro domain, is capable of maintaining neural pathways in a mammal (See Examples 4 and 6 below) . These findings indicate that oral and parenteral administration are viable means for administering morphogens to an individual. In addition, while the mature forms of certain morphogens described herein typically are sparingly soluble, the morphogen form found in milk (and mammary gland extract and colostrum) is readily soluble, probably by association of the mature, morphogenically active form with part or all of the pro domain of the intact sequence and/or by association with one or more milk components. Accordingly, the compounds provided herein also may be associated with molecules capable of enhancing their solubility in vitro or in vivo. The compounds provided herein also may be associated with molecules capable of targeting the morphogen or morphogen-stimulating agent to nerve tissue. For example, an antibody, antibody fragm * _z, or other binding protein that interacts specifically with a surface molecule on nerve tissue cells, including neuronal or glial cells, may be used. Useful targeting molecules may be designed, for example, using the single chain binding site technology disclosed, for example, in U.S. Pat. No. 5,091,513. As described above, the morphogens provided herein share significant sequence homology in the C-terminal active domains. By contrast, the sequences typically diverge significantly in the sequences which define the pro domain. Accordingly, the pro domain is thought to be morphogen-speci'ic. As described above, it is also known that the va ...ous morphogens identified to date are differentially expressed in the different tissues. Accordingly, without being limited to any given theory, it is likely that, under natural conditions in the body, selected morphogens typically act on a given tissue. Accordingly, part or all of the pro domains which have been identified associated with the active form of the morphogen in solution, may serve as targeting molecules for the morphogens described herein. For example, the pro domains may interact specifically with one or more molecules at the target tissue to direct the morphogen associated with the pro domain to that tissue. Accordingly, another useful targeting molecule for targeting morphogen to nerve tissue is part or all of a morphogen pro domain, particularly part or all of the pro domains of OP-1 or GDF-1, both of which proteins are found naturally associated with nerve tissue. Finally, the morphogens or morphogen-stimulating agents provided herein may be administered alone or in combination with other molecules known to be beneficial in maintaining neural pathways, including nerve growth factors and anti-inflammatory agents. The compounds provided herein can be formulated into pharmaceutical compositions by admixture with pharmaceutically acceptable nontoxic excipients and carriers. As noted above, such compositions may be prepared for parenteral administration, particularly in the form of liquid solutions or suspensions; for oral administration, particularly in the form of tablets or capsules; or intranasally, particularly in the form of powders, nasal drops, or aerosols. The compositions can be formulated for parenteral or oral administration to humans or other mammals in therapeutically effective amounts, e.g., amounts which provide appropriate concentrations for a time sufficient to eliminate or reduce the patient's pathological condition, to provide therapy for the neurological diseases and disorders described above, and amounts effective to enhance neural cell survival an/or to protect neurons and neural pathways in anticipation of injury to nerve tissue. As will be appreciated by those skilled in the art, the concentration of the compounds described in a therapeutic composition will vary depending upon a number of factors, including the dosage of the drug to be administered, the chemical characteristics (e.g., hydrophobicity) of the compounds employed, and the route of administration. The preferred dosage of drug to be administered also is likely to depend on such variables as the type and extent of progression of the neurological disease, the overall health status of the particular patient, the relative biological efficacy of the compound selected, the formulation of the compound excipients, and its route of administration. In general terms, the compounds of this invention may be provided in an aqueous physiological buffer solution containing about 0.1 to 10% w/v compound for parenteral administration. Typical dose ranges are from about 10 ng/kg to about 1 g/kg of body weight per day; a preferred dose range is from about 0.1 μg/kg to 100 mg/kg of body weight per day. Optimally, the morphogen dosage given in all cases is between 2-20 μg of protein per kilogram weight of the patient per day. No obvious OP-1 induced pathological lesions are induced when mature morphogen (e.g., OP-1, 20 μg) is administered daily to normal growing rats for 21 consecutive days. Moreover, 10 μg systemic injections of morphogen (e.g., OP-1) injected daily for 10 days into normal newborn mice does not produce any gross abnormalties. Since the ability of proteins and protein fragments to penetrate the blood-brain barrier may be related to their size, lipophilicity or their net ionic charge, suitable modifications of the morphogens may be formulated (e.g., by substituting pentafluorophenylalanine for phenylalanine, or by conjugation to a cationized protein such as albumin) to increase their transportability across the barrier, using standard methodologies known in the art. See, for example, Kastin et al., Pharmac. Biochem. Behav. (1979) H_:713-716; Rapoport et al.. Science (1980) 207:84-86; Pardridge et al., (1987) Biochem. Biophys. Res. Commun. 146:307-313; Riekkinen et al.,(1987) Peptides :261-265. The efficacy of these functional analogs may be assessed for example, by evaluating the ability of these compounds to induce redifferentiation of transformed cells, or enhance survival of neurons at risk of dying, as described in the Examples provided herein. In administering morphogens systemically in the methods of the present invention, preferably a large volume loading dose is used at the start of the treatment. The treatment then is continued with a maintenance dose. Further administration then can be determined by monitoring at intervals the levels of the morphogen in the blood. Where injury to neurons of a neural pathway is induced deliberately as part of, for example, a surgical procedure, the morphogen preferably is provided just prior to, or concomitant with induction of the trauma. Preferably, the morphogen is administered prophylactically in a surgical setting. Optimally, the morphogen dosage given in all cases is between 2-20 μg of protein per kilogram weight of the patient. Alternatively, an effective amount of an agent capable of stimulating endogenous morphogen levels may be administered by any of the routes described above. For example, an agent capable of stimulating morphogen production and/or secretion from nerve tissue cells may be provided to a mammal, e.g., by direct administration of the morphogen to glial cells associated with the nerve tissue to be treated. A method for identifying and testing agents capable of modulating the levels of endogenous morphogens in a given tissue is described generally herein in Example 13, and in detail in internatinal application US92/07359 (WO93/015172) , the disclosure of which is incorporated herein by reference. Briefly, candidate compounds can be identified and tested by incubating the compound in vitro with a test tissue or cells thereof, for a time sufficient to allow the compound to affect the production, i.e., the expression and/or secretion, of a morphogen produced by the cells of that tissue. Here, suitable tissue or cultured cells of a tissue preferably would comprise neurons and/or glial cells. For example, suitable tissue for testing may include cultured cells isolated from the substantia nigra, adendema glial cells, and the like. A currently preferred detection means for evaluating the level of the morphogen in culture upon exposure to the candidate compound comprises an immunoassay utilizing an antibody or other suitable binding protein capable of reacting specifically with a morphogen and being detected as part of a complex with the morphogen. Immunoassays may be performed using standard techniques known in the art and antibodies raised against a morphogen and specific for that morphogen. As described herein, morphogens may be isolated from natural-sourced material or they may be recombinantly produced. Agents capable of stimulating endogenous morphogens then may formulated into pharmaceutical preparations and administered as described herein. Where the morphogen is to be provided to a site to stimulate axon regeneration, the morphogen preferably is provided to the site in association with a biocompatible, preferably bioresorbable carrier suitable for maintaining a protein at a site in vivo, and through which a neural process may regenerate. A currently preferred carrier also comprises sufficient structure to assist direction of axonal growth. Currently preferred carriers include structural molecules such as collagen, hyaluronic acid or laminin, and/or synthetic polymers or copolymers of, for example, polylactic acid, polyglycolic acid or polybutyric acid. Currently most preferred are carriers comprising tissue extracellular matrix. These may be obtained commercially. In addition, a brain tissue-derived extracellular matrix may be prepared as described in international application US92/01968 (W092/15323) , incorporated hereinabove by reference, and/or by other means known in the art. The currently preferred means for repairing breaks in neural pathways, particularly pathways of the ■ peripheral nervous system, include providing the morphogen to the site as part of a device that includes a biocompatible membrane or casing of a dimension sufficient to span the break and having openings adapted to receive severed nerve ends. The morphogen is disposed - thin the casing, preferably dispersed throughout a suitable carrier, and is accessible to the severed nerve ends. Alternatively, the morphogen may be adsorbed onto the interior surface of the casing, or otherwise associated therewith. In addition, currently preferred casings have an impermeable exterior surface. The casing acts as a nerve guidance channel, aiding in directing axonal growth. In addition, the casing also protects the damaged nerve from immunologically-related agents which may assist in scar tissue formation. Suitable channel or casing materials include silicone or bioresorbable materials such as collagen, hyaluronic acid, laminin, polylactic acid, polyglycolic acid, polybutyric acid and the like. Additionally, although the nerve guidance channels described herein generally are tubular in shape, it should be evident to those skilled in the art that various alternative shapes may be employed. The lumen of the guidance channels may, for example, be oval or even square in cross section. Moreover the guidance channels may be constructed of two or more parts which may be clamped together to secure the nerve stumps. Nerve endings may be secured to the nerve guidance channels by means of sutures, biocompatible adhesives such as fibrin glue, or other means known in the medical art. II.1 Soluble Morphogen Complexes A currently preferred form of the morphogen useful in therapeutic formulations, having improved solubility in aqueous solutions and consisting essentially of amino acids, is a dimeric morphogenic protein comprising at least the 100 amino acid peptide sequence having the pattern of seven or more cysteine residues characteristic of the morphogen family complexed with a peptide comprising part or all of a pro region of a member of the morphogen family, or an allelic, species or other sequence variant thereof. Preferably, the dimeric morphogenic protein is complexed with two peptides. Also, the dimeric morphogenic protein preferably is noncovalently complexed with the pro region peptide or peptides. The pro region peptides also preferably comprise at least the N-terminal eighteen amino acids that define a given morphogen pro region. In a most preferred embodiment, peptides defining substantially the full length pro region are used. Other soluble forms of morphogens include dimers of the uncleaved pro forms of these proteins, as well as "hemi-dimers" wherein one subunit of the dimer is an uncleaved pro form of the protein, and the other subunit comprises the mature form of the protein, including truncated forms thereof, preferably noncovalently associated with a cleaved pro domain peptide. As described above, useful pro domains include the full length pro regions, as well as various truncated forms hereof, particularly truncated forms cleaved at proteolytic Arg-Xaa-Xaa-Arg cleavage sites. For example, in OP-1, possible pro sequences include sequences defined by residues 30-292 (full length form); 48-292; and 158-292. Soluble OP-1 complex stability is enhanced when the pro region comprises the full length form rather than a truncated form, such as the 48-292 truncated form, in that residues 30-47 show sequence homology to the N-terminal portions of other morphogens, and are believed to have particular utility in enhancing complex stability for all morphogens. Accordingly, currently preferred pro sequences are those encoding the full length form of the pro region for a given morphogen. Other pro sequences contemplated to have utility include biosynthetic pro sequences, particularly those that incorporate a sequence derived from the N-terminal portion of one or more morphogen pro sequences. As will be appreciated by those having ordinary skill in the art, useful sequences encoding the pro region may be obtained from genetic sequences encoding known morphogens. Alternatively, chimeric pro regions can be constructed from the sequences of one or more known morphogens. Still another option is to create a synthetic sequence variant of one or more known pro region sequences. In another preferred aspect, useful pro region peptides include polypeptide chains comprising an amino acid sequence encoded by a nucleic acid that hybridizes under stringent conditions with a DNA or RNA sequence encoding at least the N-terminal eighteen amino acids of the pro region sequence for OP1 or OP2, e.g., nucleotides 136-192 and 152-211 of Seq. ID No. 16' and 20, respectively. A. Isolation of Soluble morphogen complex from conditioned media or body fluid Morphogens are expressed from mammalian cells as soluble complexes. Typically, however the complex is disassociated during purification, generally by exposure to denaturants often added to the purification solutions, such as detergents, alcohols, organic solvents, chaotropic agents and compounds added to reduce the pH of the solution. Provided below is a currently preferred protocol for purifying the soluble proteins from conditioned media (or, optionally, a body fluid such as serum, cerebro-spinal or peritoneal fluid), under non-denaturing conditions. The method is rapid, reproducible and yields isolated soluble morphogen complexes in substantially pure form. Soluble morphogen complexes can be isolated from conditioned media using a simple, three step chromatographic protocol performed in the absence of denaturants. The protocol involves running the media (or body fluid) over an affinity column, followed by ion exchange and gel filtration chromatographies. The affinity column described below is a Zn-IMAC column. The present protocol has general applicability to the purification of a variety of morphogens, all of which are anticipated to be isolatable using only minor modifications of the protocol described below. An alternative protocol also envisioned to have utility an immunoaffinity column, created using standard procedures and, for example, using antibody specific for a given morphogen pro domain (complexed, for example, to a protein A-conjugated Sepharose column. ) Protocols for developing immunoaffinity columns are well described in the art, (see, for example. Guide to Protein Purification, M. Deutscher, ed.. Academic Press, San Diego, 1990, particularly sections VII and XI.) In this experiment OP-1 was expressed in mammalian CHO (Chinese hamster ovary) cells as described in the art (see, for example, international application US90/05903 (WO91/05802).) The CHO cell conditioned media containing 0.5% FBS was initially purified using Immobilized Metal-Ion Affinity Chromatography (IMAC). The soluble OP-1 complex from conditioned media binds very selectively to the Zn-IMAC resin and a high concentration of imidazole (50 mM imidazole, pH 8.0) is required for the effective elution of the bound complex. The Zn-IMAC step separates the soluble OP-1 from the bulk of the contaminating serum proteins that elute in the flow through and 35 mM imidazole wash fractions. The Zn-IMAC purified soluble OP-1 is next applied to an S-Sepharose cation-exchange column equilibrated in 20 mM NaP0 4 (pH 7.0) with 50 mM NaCl. This S-Sepharose step serves to further purify and concentrate the soluble OP-1 complex in preparation for the following gel filtration step. The protein was applied to a Sephacryl S-200HR column equilibrated in TBS. Using substantially the same protocol, soluble morphogens also may be isolated from one or more body fluids, including serum, cerebro-spinal fluid or peritoneal fluid. IMAC was performed using Chelating-Sepharose (Pharmacia) that had been charged with three column volumes of 0.2 M ZnSO.. The conditioned media was titrated to pH 7.0 and applied directly to the ZN-IMAC resin equilibrated in 20 mM HEPES (pH 7.0) with 500 mM NaCl. The Zn-IMAC resin was loaded with 80 mL of starting conditioned media per mL of resin. After loading, the column was washed with equilibration buffer and most of the contaminating proteins were eluted with 35 mM imidazole (pH 7.0) in equilibration buffer. The soluble OP-1 complex then is eluted with 50 mM imidazole (pH 8.0) in 20 mM HEPES and 500 mM NaCl. The 50 mM imidazole eluate containing the soluble OP-1 complex was diluted with nine volumes of 20 mM NaP0 4 (pH 7.0) and applied to an S-Sepharose (Pharmacia) column equilibrated in 20 mM NaPO. (pH 7.0) with 50 mM NaCl. The S-Sepharose resin was loaded with an equivalent of 800 mL of starting conditioned media per mL of resin. After loading the S-Sepharose column was washed with equilibration buffer and eluted with 100 mM NaCl followed by 300 mM and 500 mM NaCl in 20 mM NaP0 4 (pH 7.0). The 300 mM NaCl pool was further purified using gel filtration chromatography. Fifty mis of the 300 mm NaCl eluate was applied to a 5.0 X 90 cm Sephacryl S-200HR (Pharmacia) equilibrated in Tris buffered saline (TBS), 50 mM Tris, 150 mM NaCl (pH 7.4). The column was eluted at a flow rate of 5 mL/minute collecting 10 mL fractions. The apparent molecular of the soluble OP-1 was determined by comparison to protein molecular weight standards (alcohol dehydrogenase (ADH, 150 kDa), bovine serum albumin (BSA, 68 kDa), carbonic anhydrase (CA, 30 kDa) and cytochrome C (cyt C, 12.5 kDa). The purity of the S-200 column fractions was determined by separation on standard 15% polyacrylamide SDS gels stained with coomassie blue. The identity of the mature OP-1 and the pro-domain was determined by N-terminal sequence analysis after separation of the mature OP-1 from the pro-domain using standard reverse phase C18 HPLC. The soluble OP-1 complex elutes with an apparent molecular weight of 110 kDa. This agrees well with the predicted composition of the soluble OP-1 complex with one mature OP-1 dimer (35-36 kDa) associated with two pro-domains (39 kDa each). Purity of the final complex can be verified by running the appropriate fraction in a reduced 15% polyacrylamide gel. The complex components can be verified by running the complex-containing fraction from the S-200 or S- 200HR columns over a reverse phase C18 HPLC column and eluting in an acetonitrile gradient (in 0.1% TFA), using standard procedures. The complex is dissociated by this step, and the pro domain and mature species elute as separate species. These separate species then can be subjected to N-terminal sequencing using standard procedures (see, for example. Guide to Protein Purification, M. Deutscher, ed.. Academic Press, San Diego, 1990, particularly pp. 602-613), and the identity of the isolated 36kD, 39kDa proteins confirmed as mature morphogen and isolated, cleaved pro domain, respectively. N-terminal sequencing of the isolated pro domain from mammalian cell produced OP-1 revealed 2 forms of the pro region, the intact form (beginning at residue 30 of Seq. ID No. 16) and a truncated form, (beginning at residue 48 of Seq. ID No. 16.) N-terminal sequencing of the polypeptide subunit of the isolated mature species reveals a range of N-termini for the mature sequence, beginning at residues 293, 300, 313, 315, 316, and 318, of Seq. ID No. 16, all of which are active as demonstrated by the standard bone induction assay. B. In Vitro Soluble Morphogen Complex Formation As an alternative to purifying soluble complexes from culture media or a body fluid, soluble complexes may be formulated from purified pro domains and mature dimeric species. Successful complex formation apparently requires association of the components under denaturing conditions sufficient to relax the folded structure of these molecules, without affecting disulfide bonds. Preferably, the denaturing conditions mimic the environment of an intracellular vesicle sufficiently such that the cleaved pro domain has an opportunity to associate with the mature dimeric species under relaxed folding conditions. The concentration of denaturant in the solution then is decreased in a controlled, preferably step-wise manner, so as to allow proper refolding of the dimer and pro regions while maintaining the association of the pro domain with the dimer. Useful denaturants include 4-6M urea or guanidine hydrochloride (GuHCl), in buffered solutions of pH ' 4-10, preferably pH 6-8. The soluble complex then is formed by controlled dialysis or dilution into a solution having a final denaturant concentration of less than 0.1-2M urea or GuHCl, preferably 1-2 M urea of GuHCl, which then preferably can be diluted into a physiological buffer. Protein purification/renaturing procedures and considerations are well described in the art, and details for developing a suitable renaturing protocol readily can be determined by one having ordinary skill in the art. One useful text one the subject is Guide to Protein Purification, M. Deutscher, ed.. Academic Press, San Diego, 1990, particularly section V. Complex formation also may be aided by addition of one or more chaperone proteins. C. Stability of Soluble Morphogen Complexes The stability of the highly purified soluble morphogen complex in a physiological buffer, e.g., tris-buffered saline (TBS) and phosphate-buffered saline (PBS), can be enhanced by any of a number of means. Currently preferred is by means of a pro region that comprises at least the first 18 amino acids of the pro sequence (e.g., residues 30-47 of Seq. ID NO. 16 for OP-1), and preferably is the full length pro region. Residues 30-47 show sequence homology to the N-terminal portion of other morphogens and are believed to have particular utility in enhancing complex stability for all morphogens. Other useful means for enhancing the stability of soluble morphogen complexes include three classes of additives. These additives include basic amino acids (e.g., L-arginine, lysine and betaine); nonionic detergents (e.g., Tween 80 or Nonldet P-120); and carrier proteins (e.g., serum albumin and casein). Useful concentrations of these additives include 1-100 mM, preferably 10-70 mM, including 50 mM, basic amino acid;, 0.01-1.0%, preferably 0.05-0.2%, including 0.1% (v/v) nonionic detergent;, and 0.01-1.0%, preferably 0.05-0.2%, including 0.1% (w/v) carrier protein. III. Examples Example 1. Identification of Morphogen-Expressing Tissue Determining the tissue distribution of morphogens may be used to identify different morphogens expressed in a given tissue, as well as to identify new, related morphogens. Tissue distribution also may be used to identify useful morphogen-producing tissue for use in screening and identifying candidate morphogen- stimulating agents. The morphogens (or their mRNA transcripts) readily are identified in different tissues using standard methodologies and minor modifications thereof in tissues where expression may be low. For example, protein distribution may be determined using standard Western blot analysis or immunofluorescent techniques, and antibodies specific to the morphogen or morphogens of interest. Similarly, the distribution of morphogen transcripts may be determined using standard Northern hybridization protocols and transcript-specific probes. Any probe capable of hybridizing specifically to a transcript, and distinguishing the transcript of interest from other, related transcripts may be used. Because the morphogens described herein share such high sequence homology in their active, C-terminal domains. the tissue distribution of a specific morphogen transcript may best be determined using a probe specific for the pro region of the immature protein and/or the N-terminal region of the mature protein. Another useful sequence is the 3' non-coding region flanking and immediately following the stop codon. These portions of the sequence vary substantially among the morphogens of this invention, and accordingly, are specific for each protein. For example, a particularly useful Vgr-1-specific probe sequence is the PvuII-SacI fragment, a 265 bp fragment encoding both a portion of the untranslated pro region and the N-terminus of the mature sequence (see Lyons et al. (1989) PNAS 86:4554- 4558 for a description of the cDNA sequence). Similarly, particularly useful mOP-1-specific probe sequences are the BstXl-Bgll fragment, a 0.68 Kb sequence that covers approximately two-thirds of the mOP-l pro region; a StuI-StuI fragment, a 0.2 Kb sequence immediately upstream of the 7-cysteine domain; and the Earl-Pstl fragment, an 0.3 Kb fragment containing a portion of the 3'untranslated sequence (See Seq. ID No. 18, where the pro region is defined essentially by residues 30-291.) Similar approaches may be used, for example, with hOP-l (Seq. ID No. 16) or human or mouse OP-2 (Seq. ID Nos. 20 and 22.) Using these morphogen-specific probes, which may be synthetically engineered or obtained from cloned sequences, morphogen transcripts can be identified in mammalian tissue, using standard methodologies well known to those having ordinary skill in the art. Briefly, total RNA is prepared from various adult murine tissues (e.g., liver, kidney, testis, heart, brain, thymus and stomach) by a standard methodology such as by the method of Chomczyaski et al. ((1987) Anal. Biochem 162:156-159) and described below. Poly (A)+ RNA is prepared by using oligo (dT)-cellulose chromatography (e.g.. Type 7, from Pharmacia LKB Biotechnology, Inc.). Poly (A)+ RNA (generally 15 μg) from each tissue is fractionated on a 1% agarose/for aldehyde gel and transferred onto a Nytran membrane (Schleicher & Schuell) . Following the transfer, the membrane is baked at 80°C and the RNA is cross-linked under UN light (generally 30 seconds at 1 mW/cm 2 ) . Prior to hybridization, the appropriate probe is denatured by heating. The hybridization is carried out in a lucite cylinder rotating in a roller bottle apparatus at approximately 1 rev/min for approximately 15 hours at 37°C using a hybridization mix of 40% formamide, 5 x Denhardts, 5 x SSPE, and 0.1% SDS. Following hybridization, the non-specific counts are washed off the filters in 0.1 x SSPE, 0.1% SDS at 50°C. Examples demonstrating the tissue distribution of various morphogens, including Vgr-1, OP-1, BMP2, BMP3, BMP4, BMP5, GDF-1, and OP-2 in developing and adult tissue are disclosed in international application US92/01968 (W092/15323), and in Ozkaynak, et al., (1991) Biochem. Biophys. Res. Commn. 179:116-123, and Ozkaynak, et al. (1992) J. Biol.Chem. 267: 25220-25227. Using the general probing methodology described herein, northern blot hybridizations using probes specific for these morphogens to probe brain, spleen, lung, heart, liver and kidney tissue indicate that kidney-related tissue appears to be the primary expression source for OP-1, with brain, heart and lung tissues being secondary sources. Lung tissue appears to be the primary tissue expression source for Vgr-1, BMP5, BMP4 and BMP3. Lower levels of Vgr-1 also are seen in kidney and heart tissue, while the liver appears to be a seen in kidney and heart tissue, while the liver appears to be a secondary expression source for BMP5, and the spleen appears to be a secondary expression source for BMP4. GDF-1 appears to be expressed primarily in brain tissue. To date, OP-2 appears to be expressed primarily in early embryonic tissue. Specifically, northern blots of murine embryos and 6- day post-natal animals shows abundant OP2 expression in 8-day embryos. Expression is reduced significantly in 17-day embryos and is not detected in post-natal animals. Example 2. Morphogen Localization in the Nervous System Morphogens have been identified in developing and adult rat brain and spinal cord tissue, as determined both by northern blot hybridization of morphogen- specific probes to mRNA extracts from developing and adult nerve tissue (see Example 1, above) and by immunolocalization studies. For example, northern blot analysis of developing rat tissue has identified significant OP-1 mRNA transcript expression in the CNS international application US92/01968 (W092/15323) , and Ozkaynak et al. (1991) Biochem. Biophys. Res. Comm., 179:11623 and Ozkaynak, et al. (1992) J. Biol. Chem. 267:25220-25227. GDF-1 mRNA appears to be expressed primarily in developing and adult nerve tissue, specifically in the brain, including the cerebellum and brain stem, spinal cord and peripheral nerves (Lee, S. (1991) PNAS 88: 4250-4254). BMP2B (also referred in the art as BMP4) and Vgr-1 transcripts also have been reported to be expressed in nerve tissue (Jones et al. (1991) Development 111:531-542), although the nerve tissue does not appear to be the primary expression tissue for these genes (Ozkaynak, et al., (1992) J. Biol. Chem. 26χ:25220-25227. Specifically, CBMP2 transcripts are reported in the region of the diencephalon associated with pituitary development, and Vgr-1 transcripts are reported in the anteroposterior axis of the CNS, including in the roof plate of the developing neural tube, as well as in the cells immediately adjacent the floor plate of the developing neural tube. In older rats, Vgr-1 transcripts are reported in developing hippocampus tissue. In addition, the genes encoding OP-1 and BMP2 originally were identified by probing human hippocampus cDNA libraries. Immunolocalization studies, performed using standard methodologies known in the art and disclosed in international application US92/01968 (W092/15323) , the disclosure of which is incorporated herein, localized OP-l expression to particular areas of developing and adult rat brain and spinal cord tissue. Specifically, OP-l protein expression was assessed in adult (2-3 months old) and five or six-day old mouse embryonic nerve tissue, using standard morphogen- specific antisera, specifically, rabbit anti-OPl antisera, made using standard antibody protocols known in the art and preferably purified on an OP-l affinity column. The antibody itself was labelled using standard fluorescent labelling techniques, or a labelled anti-rabbit IgG molecule was used to visualize bound OP-l antibody. As can be seen in FIG 1A and IB, immunofluorescence staining demonstrates the presence of OP-l in adult rat central nervous system (CNS.) Similar and extensive staining is seen in both the brain (1A) and spinal cord (IB). OP-l appears to be localized predominantly to the extracellular matrix of the grey matter (neuronal cell bodies) , distinctly present in all areas except the cell bodies themselves. In white matter, formed mainly of myelinated nerve fibers, staining appears to be confined to astrocytes (glial cells). A similar staining pattern also was seen in newborn rat (10 day old) brain sections. In addition, OP-l has been specifically localized in the substantia nigra, which is composed primarily of striatal basal ganglia, a system of accessory motor neurons that function is association with the cerebral cortex and corticospinal system. Dysfunctions in this subpopulation or system of neurons are associated with a number of neuropathies, including Huntington's chorea and Parkinson's disease. OP1 also has been localized at adendema glial cells, known to secrete factors into the cerebrospinal fluid, and which occur around the intraventricular valve, coroid fissure, and central canal of the brain in both developing and adult rat. Finally, morphogen inhibition in developing embryos inhibits nerve tissue development. Specifically, 9-day mouse embryo cells, cultured i-n vitro under standard culturing conditions, were incubated in the presence and absence of an OP-1-specific monoclonal antibody prepared using recombinantly produced, purified mature OP-l and the immunogen. The antibody was prepared using standard antibody production means well known in the art and as described generally in Example 13. After two days, the effect of the antibody on the developing embryo was evaluated by histology. As determined by histological examination, the OP-1- specific antibody specifically inhibits eye lobe formation in the developing embryo. In particular, the diencephalon outgrowth does not develop. In addition, the heart is malformed and enlarged. Moreover, in separate immunolocalization studies on embryo sections with labelled OP-l specific antibody, the OP-1-specific antibody localizes to neural epithelia. The endogenous morphogens which act on neuronal cells may be expressed and secreted by nerve tissue cells, e.g., by neurons and/or glial cells associated with the neurons, and/or they may be transported to the neurons by the cerebrospinal fluid and/or bloodstream. Recently, OP-l has been identified in the human blood (See Example 9, below). In addition, transplanted Schwann cells recently have been shown to stimulate nerve fiber formation in rat spinal cord, including inducing vascularization and myelin sheath formation around at least some of the new neuronal processes (Bunge (1991) Exp. Neurology 114:254-257.) The regenerative property of these cells may be mediated by the secretion of a morphogen by the Schwann cells. Example 3. Morphogen Enhancement of Neuronal Cell Survival The morphogens described herein enhance cell survival, particularly of neuronal cells at risk of dying. For example, fully differentiated neurons are non-mitotic and die in vitro when cultured under standard mammalian cell culture conditions, using a chemically defined or low serum medium known in the art, (see, for example, Charness (1986) J. Biol. Chem. 26_:3164-3169 and Freese et al. (1990) Brain Res. 521:254-264. ) However, if a primary culture of non- mitotic neuronal cells is treated with a morphogen, the survival of these cells is enhanced significantly. For example, a primary culture of striatal basal ganglia isolated from the substantia nigra of adult rat brain was prepared using standard procedures, e.g., by dissociation by trituration with pasteur pipette of substania nigra tissue, using standard tissue culturing protocols, and grown in a low serum medium, e.g., containing 50% DMEM (Dulbecco's modified Eagle's medium), 50% F-12 medium, heat inactivated horse serum supplemented with penicillin/streptomycin and 4 g/1 glucose. Under standard culture conditions, these cells are undergoing significant cell death by three weeks when cultured in a serum-free medium. Cell death is evidenced morphologically by the inability of cells to remain adherent and by changes in their ultrastructural characteristics, e.g., by chromatin clumping and organelle disintegration. In this example, the cultured basal ganglia were were treated with chemically defined medium conditioned with 0.1-100 ng/ml OP-l. Fresh, morphogen-conditioned medium was provided to the cells every 3-4 days. Cell survival was enhanced significantly and was dose dependent upon the level of OP-l added: cell death decreased significantly as the concentration of OP-l was increased in cell cultures. Specifically, cells remained adherent and continued to maintain the morphology of viable differentiated neurons. In the absence of morphogen treatment, the majority of the cultured cells dissociated and underwent cell necrosis. Dysfunctions in the basal ganglia of the sustantia nigra are associated with Huntington's chorea and parkinsonism in vivo. The ability of the morphogens defined herein to enhance neuron survival indicates that these morphogens will be useful as part of a therapy to enhance survival of neuronal cells at risk of dying in vivo due, for example, to a neuropathy or chemical or mechanical trauma. It is particularly anticipated that these morphogens will provide a useful therapeutic agent to treat neuropathies which affect the striatal basal ganglia, including Huntington's chorea and Parkinson's disease. For clinical applications, the morphogen may be administered or, alternatively, a morphogen-stimulating agent may be administered. Example 4. Morphogen-Induced Redifferentiation of Transformed Cells The morphogens described herein also induce redifferentiation of transformed cells to a morphology characteristic of untransformed cells. In particular, the morphogens are capable of inducing redifferentiation of transformed cells of neuronal origin to a morphology characteristic of untransformed neurons. The example provided below details morphogen induced redifferentiation of a transformed human cell line of neuronal origin, NG105-115. Morphogen-induced redifferentiation of transformed cells also has been shown in mouse neuroblastoma cells (N1E-115) and in human embryo carcimona cells (see international application US92/01968 (W092/15323) . NG108-15 is a transformed hybrid cell line produced by fusing neuroblastoma x glioma cells (obtained from America Type Tissue Culture, Rockville, MD), and exhibiting a morphology characteristic of transformed embryonic neurons, e.g., having a fibroblastic morphology. Specifically, the cells have polygonal cell bodies, short, spike-like processes and make few contacts with neighboring cells (see FIG. 1A) . Incubation of NG108-15 cells, cultured in a chemically defined, serum-free medium, with 0.1 to 300 ng/ml of OP-l for four hours induces an orderly, dose-dependent change in cell morphology. In the experiment NG108-15 cells were subcultured on poly-L-ly; ine coated 6-well plates. Each well contained 40-50,000 cells in 2.5 ml of chemically defined medium. On the third day 2.5 μl of OP-l in 60% ethanol containing 0.025% trifluoroacetic was added to each well. OP-l concentrations of 0-300 ng/ml were tested. Typically, the media was changed daily with new aliquots of OP-l, although morphogenesis can be induced by a single four hour incubation with OP-l. In addition, OP-l concentrations of 10 ng/ml were sufficient to induce redifferentiation. After one day, hOP-1-treated cells undergo a significant change in their cellular ultrastructure, including rounding of the soma, increase in phase brightness and extension of the short neurite processes. After two days, cells treated with OP-l begin to form epithelioid sheets, which provide the basis for the growth of mutilayered aggregates at three day's post-treatment. By four days, the great majority of OP-1-treated cells are associated in tightly-packed, mutilayered aggregates (Fig. IB). Fig. 2 plots the mean number of multi- layered aggregates or cell clumps identified in twenty randomly selected fields from six independent experiments, as a function of morphogen concentration. Forty ng/ml of OP-l is sufficient for half maximum induction of cell aggregation. The morphogen-induced redifferentiation occurred without any associated changes in DNA synthesis, cell division, or cell viability, making it unlikely that the morphologic changes were secondary to cell differentiation or a toxic effect of hOP-l. Moreover, the OP-1-induced morphogenesis does not inhibit cell division, as determined by 3 H-thymidine uptake, unlike other molecules which have been shown to stimulate differentiation of transformed cells, such as butyrate, DMSO, retanoic acid or Forskolin. The data indicate that OP-l can maintain cell stability and viability after inducing redifferentiation. In addition, the effects are morphogen specific, and redifferentiation is not induced when NG108-15 cells are incubated with 0.1-40 ng/ml TGF-β. The experiments also have been performed with highly purified soluble morphogen (e.g., mature OP1 associated with its pro domain) which also specifically induced redifferentiation of NG108-15 cells. The morphogens described herein accordingly provide useful therapeutic agents for the treatment of neoplasias and neoplastic lesions of the nervous system, particularly in the treatment of neuroblastomas, including retmoblastomas, and gliomas. The morphogens themselves may be administered or, alternatively, a morphogen-stimulating agent may be administered. Example 5. Nerve Tissue Protection from Chemical Trauma The ability of the morphogens described herein to enhance survival of neuronal cells and to induce cell aggregation and cell-cell adhesion in redifferentiated cells, indicates that the morphogens will be useful as therapeutic agents to maintain neural pathways by protecting the cells defining the pathway from the damage caused by chemical trauma. In particular, the morphogens can protect neurons, including developing neurons, from the effects of toxins known to inhibit the proliferation and migration of neurons and to interfere with cell-cell adhesion. Examples of such toxins include ethanol, one or more of the toxins present in cigarette smoke, and a variety of opiates. The toxic effects of ethanol on developing neurons induces the neurological damage manifested in fetal alcohol syndrome. The morphogens also may protect neurons from the cytoxic effects associated with excitatory amino acids such as glutamate. For example, ethanol inhibits the cell-cell adhesion effects in Uiced in morphogen-treated NG108-15 cells when provided to these cells at a concentration of 25-50 mM. Half maximal inhibition can be achieved with 5-10 mM ethanol, the concentration of blood alcohol in an adult following ingestion of a single alcoholic beverage. Ethanol likely interferes with the homophilic binding of CAMs between cells, rather than their induction, as morphogen-induced N-CAM levels are unaffected by ethanol. Moreover, the inhibitory effect is inversely proportional to morphogen concentration. Accordingly, it is envisioned that administration of a morphogen or morphogen-stimulating agent to neurons, particularly developing neurons, at risk of damage from exposure to toxins such as ethanol, may protect these cells from nerve tissue damage by overcoming the toxin's inhibitory effects. The morphogens described herein also are useful in therapies to treat damaged neural pathways resulting from a neuropathy induced by exposure to these toxins. Example 6. Morphogen-Induced CAM Expression The morphogens described herein induce CAM expression, particularly N-CAM expression, as part of their induction of morphogenesis. CAMs are morphoregulatory molecules identified in all tissues as an essential step in tissue development. N-CAMs, which comprise at least 3 isoforms (N-CAM-180, N-CAM-140 and N-CAM-120, where "180", "140" and "120" indicate the apparent molecular weights of the isoforms as measured by polyacrylamide gel electrophoresis) are expressed at least transiently in developing tissues, and permanently in nerve tissue. Both the N-CAM-180 and N- CAM-140 isoforms are expressed in both developing and adult tissue. The N-CAM-120 isoform is found only in adult tissue. Another neural CAM is LI. N-CAMs are implicated in appropriate neural development, including appropriate nuerulation, neuronal migration, fasciculation, and synaptogenesis. Inhibition of N-CAM production, as by complexing the molecule with an N-CAM-specific antibody, inhibits retina organization, including retinal axon migration, and axon regeneration in the peripheral nervous system, as well as axon synapsis with target muscle cells. In addition, significant evidence indicates that physical or chemical trauma to neurons, oncogenic transformation and some genetic neurological disorders are accompanied by changes in CAM expression, which alter the adhesive or migratory behavior of these cells. Specifically, increased N-CAM levels are reported in Huntington's disease striatum (e.g., striatal basal ganglia), and decreased adhesion is noted in Alzheimer's disease. The morphogens described herein can stimulate CAM production, particularly LI and N-CAM production, including all three isoforms of the N-CAM molecule. For example, N-CAM expression is stimulated significantly in morphogen-treated NG108-15 cells. Untreated NG108-15 cells exhibit a fibroblastic, or minimally differentiated morphology and express only the 180 and 140 isoforms of N-CAM normally associated with a developing cell. Following morphogen treatment these cells exhibit a morphology characteristic of adult neurons and express enhanced levels of all three N-CAM isoforms. Using a similar protocol as described in the example below, morphogen treatment of NG108-15 cells also induced LI expression. In this example NG108-15 cells were cultured for 4 days in the presence of increasing concentrations of OP-l and standard Western blots performed on whole cells extracts. N-CAM isoforms were detected with an antibody which crossreacts with all three isoforms, mAb H28.123, obtained from Sigma Chemical Co., St. Louis, the different isoforms being distinguishable by their different mobilities on an electrophoresis gel. Control NG108-15 cells (untreated) express both the 140 kDa and the 180 kDa isoforms, but not the 120 kDa, as determined by western blot analyses using up to 100 μg of protein. Treatment of NG108-15 cells with OP-l resulted in a dose-dependent increase in the expression of the 180 kDa and 140 kDa isoforms, as well as the induction of the 120 kDa isoform. See Fig. 2A and 2B. Fig. 2B is a Western blot of OPl-treated NG108-15 cell extracts, probed with mAb H28.123, showing the induction of all three isoforms. Fig. 2A is a dose response curve of N-CAM-180 and N-CAM-140 induction as a function of morphogen concentration. N- CAM-120 is not shown in the graph as it could not be quantitated in control cells. However, as is clearly evident from the Western blot in Fig. 2A, N-CAM-120 is induced in response to morphogen treatment. The differential induction of N-CAM 180 and 140 isoforms seen may be because constitutive expression of the 140 isoform is close to maximum. The increase in N-CAM expression corresponded in a dose-dependent manner with the morphogen induction of multicellular aggregates. Compare Fig. 2A and Fig 3. Fig. 3 graphs the mean number of multilayered aggregates (clumps) counted per 20 randomly selected fields in 6 independent experiments, versus the concentration of morphogen. The induction of the 120 isoform also indicates that morphogen-induced redifferentiation of transformed cells stimulates not only redifferentiation of these cells from a transformed phenotype, but also differentiation to a phenotype corresponding to a developed cell. Standard immunolocalization studies performed with the mAb H28.123 on morphogen-treated cells show N-CAM cluster formation associated with the periphery and processes of treated cells and no reactivity with untreated cells. Moreover, morphogen treatment does not appear to inhibit cell division as determined by cell counting or 3 H-thymidine uptake. Finally, known chemical differentiating agents, such as Forskolin and dimethylsulfoxide do not induce N-CAM production. In addition, the cell aggregation effects of OP-l on NG108-15 cells can be inhibited with anti-N-CAM antibodies or antisense N-CAM oligonucleotides. Antisense oligonucleotides can be made synthetically on a nucleotide synthesizer, using standard means known in the art. Preferably, phosphorothioate oligonucleotides ("S-oligos") are prepared, to enhance transport of the nucleotides across cell membranes. Concentrations of both N-CAM antibodies and N-CAM antisense oliognucleotides sufficient to inhibit N-CAM induction also inhibited formation of multilayered cell aggregates. Specifically, incubation of morphogen- treated NG108-115 cells with 0.3-3 μM N-CAM antisense S-oligos, 5-500 μM unmodified N-CAM antisense oligos, or 10 μg/ml mAb H28.123 significantly inhibits cell aggregation. It is likely that morphogen treatment also stimulates other CAMs, as inhibition is not complete. The experiments also have been performed with soluble morphogen (e.g., mature OP-l associated with its pro domain) which also specifically induced CAM expression. The morphogens described herein are useful as therapeutic agents to treat neurological disorders associated with altered CAM levels, particularly N-CAM levels, such as Huntington's chorea and Alzheimers' disease, and the like. In clinical applications, the morphogens themselves may be administered or, alternatively, a morphogen-stimulating agent may be administered. The efficacy of the morphogens described herein to affect N-CAM expression may be assessed in vitro using a suitable cell line and the methods described herein. In addition to a transformed cell line, N-CAM expression can be assayed in a primary cell culture of neural or glial cells, following the procedures described herein. The efficacy of morphogen treatment on N-CAM expression in vivo may be evaluated by tissue biopsy as described in Example 9, below, and detecting N-CAM molecules with an N-CAM-specific antibody, such as mAb H28.123, or using the animal model described in Example 11. Alternatively, the level of N-CAM proteins or protein fragments present in cerebrospinal fluid or serum also may be detected to evaluate the effect of morphogen treatment. N-CAM molecules are known to slough off cell surfaces and have been detected in both serum and cerebrospinal fluid. In addition, altered levels of the soluble form of N-CAM are associated with normal pressure hydrocephalus and type II schizophrenia. N-CAM fluid levels may be detected following the procedure described in Example 9 and using an N-CAM specific antibody, such as mAb H28.123. Example 7. Morphogen-Induced Nerve Gap Repair (PNS) The morphogens described herein also stimulate peripheral nervous system axonal growth over extended distances allowing repair and regeneration of damaged neural pathways. While neurons of the peripheral nervous system can sprout new processes following injury, without guidance these sproutings typically fail to connect appropriately and die. Where the break is extensive, e.g., greater than 5 or 10 mm, regeneration is poor or nonexistent. In this example morphogen stimulation of nerve regeneration was assessed using the rat sciatic nerve model. The rat sciatic nerve can regenerate spontaneously across a 5 mm gap, and occasionally across a 10 mm gap, provided that the severed ends are inserted in a saline-filled nerve guidance channel. In this experiment, nerve regeneration across a 12mm gap was tested. Adult female Sprague-Dawley rats (Charles River Laboratories, Inc.) weighing 230-250 g were anesthetized with intraperitoneal injections of sodium pentobarbital 35 mg/kg body weight). A skin incision was made parallel and just posterior to the femur. The avascular intermuscular plane between vastus lateralis and hamstring muscles were entered and followed to the loose fibroareolar tissue surrounding the sciatic nerve. The loose tissue was divided longitudinally thereby freeing the sciatic nerve over its full extent without devascularizing any portion. Under a surgical microscope the sciatic nerves were transected with microscissors at mid-thigh and grafted with an OP-l gel graft that separated the nerve stumps by 12 mm. The graft region was encased in a silicone tube 20 mm in length with a 1.5 mm inner diameter,the interior of which was filled a morphogen solution. Specifically, The central 12 mm of the tube consisted of an OP-l gel prepared by mixing 1 to 5 μg of substantially pure CHO- produced recombinant OP-l with approximately 100 μl of MATRIGEL™ (from Collaborative Research, Inc., Bedford, MA), an extracellular matrix extract derived from mouse sarcoma tissue, and containing solubilized tissue basement membrane, including laminin, type IV collagen, heparin sulfate, proteoglycan and entactin, in phosphate-buffered saline. The OP-1-filled tube was implanted directly into the defect site, allowing 4 mm on each end to insert the nerve stumps. Each stump was abutted against the OP-l gel and was secured in the silicone tube by three stitches of commercially available surgical 10-0 nylon through the epineurium, the fascicle protective sheath. In addition to OP-l gel grafts, empty silicone tubes, silicone tubes filled with gel only and "reverse" autografts, wherein 12 mm transected segments of the animal's sciatic nerve were rotated 180° prior to suturing, were grafted as controls. All experiments were performed in quadruplicate. All wounds were closed by wound clips that were removed after 10 days. All rats were grafted on both legs. At 3 weeks the animals were sacrificed, and the grafted segments removed and frozen on dry ice immediately. Frozen sections then were cut throughout the graft site, and examined for axonal regeneration by immunofluorescent staining using anti-neurofilament antibodies labeled with flurocein (obtained from Sigma Chemical Co., St. Louis). Regeneration of the sciatic nerve occurred across the entire 12 mm distance in all graft sites wherein the gap was filled with the OP-l gel. By contrast, empty silicone tubes and reverse autografts did not show nerve regeneration, and only one graft site containing the gel alone showed axon regeneration. Example 8. Morphogen-Induced Nerve Gap Repair (CNS) Following axonal damage in vivo the CNS neurons are unable to resprout processes. Accordingly, trauma to CNS nerve tissue, including the spinal cord, optic nerve and retina, severely damages or destroys the neural pathways defined by these cells. Peripheral nerve grafts have been used in an effort to bypass CNS axonal damage. Successful autologous graft repair to date apparently requires that the graft site occur near the CNS neuronal cell body, and a primary result of CNS axotomy is neuronal cell death. The efficacy of morphogens described herein on CNS nerve repair, may be evaluated using a rat crushed optic nerve model such as the one described by Bignami et al., (1979) Exp. Eye Res. 28: 63-69, the disclosure of which is incorporated herein by reference. Briefly, and as described therein, laboratory rats (e.g., from Charles River Laboratories, Wilmington, MA) are anesthesized using standard surgical procedures, and the optic nerve crushed by pulling the eye gently out of the orbit. inserting a watchmaker forceps behind the eyeball and squeezing the optic nerve with the forceps for 15 seconds, followed by a 30 second interval and second 15 second squeeze. Rats are sacrificed at different time intervals, e.g., at 48 hours, and at 3, 4, 11, 15 and 18 days after operation. The effect of morphogen on optic nerve repair can be assessed by performing the experiment in duplicate and providing morphogen or PBS (e.g., 25 μl solution, and 25 μg morphogen) to the optic nerve, e.g., just prior to the operation, concommitant with the operation, or at specific times after the operation. In the absence of therapy, the surgery induces glial scarring of the crushed nerve, as determined by immunofluoresence staining for glial fibrillary acidic protein (GFA), a marker protein for glial scarring, and by histology. Indirect immunofluoresence on air-dried cryostat sections as described in Bignami et al. (1974) J. Comp. Neur. 153: 27-38, using commercially available antibodies to GFA (e.g., Sigma Chemical Co., St. Louis). Reduced levels of GFA are anticipated in animals treated with the morphogen, evidencing the ability of morphogens to inhibit glial scar formation and to stimulate optic nerve regeneration. Example 9. Nerve Tissue Diagnostics Morphogen localization in nerve tissue can be used as part of a method for diagnosing a neurological disorder or neuropathy. The method may be particularly advantageous for diagnosing neuropathies of brain tissue. Specifically, a biopsy of brain tissue is performed on a patient at risk, using standard procedures known in the medical art. Morphogen expression associated with the biopsied tissue then is assessed using standard methodologies, as by immunolocalization, using standard immunofluorescence techniques in concert with morphogen-specific antisera or monoclonal antibodies. Specifically, the biopsied tissue is thin sectioned using standard methodologies known in the art, and fluorescently labelled (or otherwise detectable) antibodies incubated with the tissue under conditions sufficient to allow specific antigen-antibody complex formation. The presence and quantity of complex formed then is detected and compared with a predetermined standard or reference value. Detection of altered levels of morphogen present in the tissue then may be used as an indicator of tissue dysfunction. Alternatively, fluctuation in morphogen levels may be assessed by monitoring morphogen transcription levels, either by standard northern blot analysis or in situ hybridization, using a labelled probe capable of hybridizing specifically to morphogen RNA and standard RNA hybridization protocols well described in the art. Fluctuations in morphogen levels present in the cerebrospinal fluid or bloodstream also may be used to evaluate nerve tissue viability. For example, morphogens are detected associated with adendema cells which are known to secrete factors into the cerebrospinal fluid, and are localized generally associated with glial cells, and in the extracellular matrix, but not with neuronal cell bodies. Accordingly, the cerebrospinal fluid may be a natural means of morphogen transport. Alternatively, morphogens may be released from dying cells into cerebrospinal fluid. In addition, OP-l recently has been identified in human blood, which also may be a means of morphogen transport, and/or a repository for the contents of dying cells. l Spinal fluid may be obtained from an individual by a standard lumbar puncture, using standard methodologies known in the medical art. Similarly, serum samples may be obtained by standard venipuncture and serum prepared by centrifugation at 3,000 RPM for ten minutes. The presence of morphogen in the serum or cerebral spinal fluid then may be assessed by standard Western blot (immunoblot) , ELISA or RIA procedures. Briefly, for example, with the ELISA, samples may be diluted in an appropriate buffer, such as phosphate- buffered saline, and 50 μl aliquots allowed to absorb to flat bottomed wells in microtitre plates pre-coated with morphogen-specific antibody, and allowed to incubate for 18 hours at 4°C. Plates then may be washed with a standard buffer and incubated with 50 μl aliquots of a second morphogen-specific antibody conjugated with a detecting agent, e.g., biotin, in an appropriate buffer, for 90 minutes at room temperature. Morphogen-antibody complexes then may be detected using standard procedures. Alternatively, a morphogen-specific affinity column may be created using, for example, morphogen-specific antibodies adsorbed to a column matrix, and passing the fluid sample through the matrix to selectively extract the morphogen of interest. The morphogen then is eluted. A suitable elution buffer may be determined empirically by determining appropriate binding and elution conditions first with a control (e.g., purified, recombinantly-produced morphogen. ) Fractions then are tested for the presence of the morphogen by standard immunoblot, and confirmed by N-terminal sequencing. Morphogen concentrations in serum or other fluid samples then may be determined using standard portein quantification techniques, including by spectrophotometric absorbance or by quantitation by ELISA or RIA antibody assays. Using this procedure, OP-l has been identified in serum. OP-l was detected in human serum using the following assay. A monoclonal antibody raised against mammalian, recombinantly produced OP-l using standard immunology techniques well described in the art and described generally in Example 13, was immobilized by passing the antibody over an activated agarose gel (e.g., Affi-Gel™ , from Bio-Rad Laboratories, Richmond, CA, prepared following manufacturer's instructions), and used to purify OP-l from serum. Human serum then was passed over the column and eluted with 3M K-thiocyanate. K-thiocyanante fractions then were dialyzed in 6M urea, 20mM PO., pH 7.0, applied to a C8 HPLC column, and eluted with a 20 minute, 25-50% acetonitrile/0.1% TFA gradient. Mature, recombinantly produced OP-l homodimers elute between 20-22 minutes. Fractions then were collected and tested for the presence of OP-l by standard immunoblot. Fig. 4 is an immunoblot showing OP-l in human sera under reducing and oxidized conditions. In the figure, lanes 1 and 4 are OP-l standards, run under oxidized (lane 1) and reduced (lane 4) conditions. Lane 5 shows molecular weight markers at 17, 27 and 39 kDa. Lanes 2 and 3 are human sera OP-l, run under oxidized (lane 2) and reduced (lane 3) conditions. Morphogens may be used in diagnostic applications by comparing the quantity of morphogen present in a body fluid sample with a predetermined reference value, with fluctuations in fluid morphogen levels indicating a change in the status of nerve tissue. Alternatively, fluctuations in the level of endogenous morphogen antibodies may be detected by this method, most likely in serum, using an antibody or other binding protein capable of interacting specifically with the endogenous morphogen antibody. Detected fluctuations in the levels of the endogenous antibody may be used as indicators of a change in tissue status. Example 10. Alleviation of Immune Response-Mediated Nerve Tissue Damage The morphogens described herein may be used to alleviate immunologically-related damage to nerve tissue. Details of this damage and the use of morphogens to alleviate this injury are disclosed in international application US92/07358 (WO93/04692) . A primary source of such damage to nerve tissue follows hypoxia or ischemia-reperfusion of a blood supply to a neural pathway, such as may result from an embolic stroke, or may be induced during a surgical procedure. As described in international application US92/07358 (WO93/04692) , morphogens have been shown to alleviate damage to myocardial tissue following ischemia- reperfusion of the blood supply to the tissue. The 5 effect of morphogens on alleviating immunologically- related damage to nerve tissue may be assessed using methodologies and models known to those skilled in the art and described below. 10 For example, the rabbit embolic stroke model provides a useful method for assessing the effect of morphogens on tissue injury following cerebral ischemia-reperfusion. The protocol disclosed below is essentially that of Phillips et al. (1989) Annals of 1. eurology 2JS:281-285, the disclosure of which is herein ticorporated by reference. Briefly, white New England abbits (2-3kg) are anesthetized and placed on a respirator. The intracranial circulation then is selectively catheterized by the Seldinger technique. 20 Baseline cerebral angiography then is performed, employing a digital substration unit. The distal internal carotid artery or its branches then is selectively embolized with 0.035 ml of 18-hour-aged autol-jgous thrombus. Arterial occlusion is documented 5 by repeat angiography immediately after embolization. After a time sufficient to induce cerebral infarcts (15 minutes or 90 minutes), reperfusion is induced by administering a bolus of a reperfusion agent such as the TPA analogue FB-FB-CF (e.g., 0.8 mg/kg over 2 0 minutes). The effect of morphogen on cerebral infarcts can be assessed by administering varying concentrations of morphogens, e.g., OP-l, at different times following 35 embolization and/or reperfusion. The rabbits are sacrificed 3-14 days post embolization and their brains prepared for neuropathological examination by fixing by immersion in 10% neutral buffered formation for at least 2 weeks. The brains then are sectioned in a coronal plane at 2-3 mm intervals, numbered and submitted for standard histological processing in paraffin, and the degree of nerve tissue necrosis determined visually. Morphogen-treated animals are anticipated to reduce or significantly inhibit nerve tissue necrosis following cerebral ischemia-reperfusion in the test animals as determined by histology comparison with nontreated animals. Example 11. Animal Model for Assessing Morphogen Efficacy In Vivo The in vivo activities of the morphogens described herein also are assessed readily in an animal model as described herein. A suitable animal, preferably exhibiting nerve tissue damage, for example, genetically or environmentally induced, is injected intracerebrally with an effective amount of a morphogen in a suitable therapeutic formulation, such as phosphate-buffered saline, pH 7. The morphogen preferably is injected within the area of the affected neurons. The affected tissue is excised at a subsequent time point and the tissue evaluated morphologically and/or by evaluation of an appropriate biochemical marker (e.g., by morphogen or N-CAM localization; or by measuring the dose-dependent effect on a biochemical marker for CNS neurotrophic activity or for CNS tissue damage, using for example, glial fibrillary acidic protein as the marker. The dosage and incubation time will vary with the animal to be tested. Suitable dosage ranges for different species may be determined by comparison with established animal models. Presented below is an exemplary protocol for a rat brain stab model. Briefly, male Long Evans rats, obtained from standard commercial sources, are anesthesized and the head area prepared for surgery. The calvariae is exposed using standard surgical procedures and a hole drilled toward the center of each lobe using a 0.035K wire, just piercing the calvariae. 25μl solutions containing either morphogen (e.g., OP-l, 25μg) or PBS then is provided to each of the holes by Hamilton syringe. Solutions are delivered to a depth approximately 3 mm below the surface, into the underlying cortex, corpus callosum and hippocampus. The skin then is sutured and the animal allowed to recover. Three days post surgery, rats are sacrificed by decapitation and their brains processed for sectioning. Scar tissue formation is evaluated by immunofluoresence staining for glial fibrillary acidic protein, a marker protein for glial scarring, to qualitatively determine the degree of scar formation. Glial fibrillary acidic protein antibodies are available commercially, e.g., from Sigma Chemical Co., St. Louis, MO. Sections also are probed with anti-OP-1 antibodies to determine the presence of OP-l. Reduced levels of glial fibrillary acidic protein are anticipated in the tissue sections of animals treated with the morphogen, evidencing the ability of morphogens to inhibit glial scar formation and stimulate nerve regeneration. Example 12. In Vitro Model for Evaluating Morphogen Species Transport Across the Blood-Brain Barrier. Described below is an in vitro method for evaluating the facility with which selected morphogen species likely will pass across the blood-brain barrier. A detailed description of the model and protocol are provided by Audus et al. (1987) Ann. N.Y. Acad. Sci. 507:9-18, the disclosure of which is incorporated herein by reference. Briefly, microvessel endothelial cells are isolated from the cerebral gray matter of fresh bovine brains. Brains are obtained from a local slaughter house and transported to the laboratory in ice cold minimum essential medium (MEM) with antibiotics. Under sterile conditions the large surface blood vessels and meninges are removed using standard dissection procedures. The cortical gray matter is removed by aspiration, then minced into cubes of about 1mm. The minced gray matter then is incubated with 0.5% dispase (BMB, Indianapolis, IN) for 3 hours at 37° C in a shaking water bath. Following the 3 hour digestion, the mixture is concentrated by centrifugation (1000 x g for 10 min.), then resuspended in 13% dextran and centrifuged for 10 min. at 5800 x g. Supernatant fat, cell debris and myelin are discarded and the crude microvessel pellet resuspended in 1 mg/ml collagenase/dispase and incubated in a shaking water bath for 5 hours at 37° C. After the 5-hour digestion, the microvessel suspension is applied to a pre-established 50% Percoll gradient and centrifuged for 10 min at 1000 x g. The band containing purified endothelial cells (second band from the top of the gradient) is removed and washed two times with culture medium (e.g., 50% MEM/50% F-12 nutrient mix). The cells are frozen ( -80° C.) in medium containing 20% DMSO and 10% horse serum for later use. After isolation, approximately 5 x 10 s cells/cm 2 are plated on culture dishes or 5-12 mμ pore size polycarbonate filters that are coated with rat collagen and fibronectin. 10-12 days after seeding the cells, cell monolayers are inspected for confluency by microscopy. Characterization of the morphological, histochemical and biochemical properties of these cells has shown that these cells possess many of the salient features of the blood-brain barrier. These features include: tight intercellular junctions, lack of membrane fenestrations, low levels of pinocytotic activity, and the presence of gamma-glutamyl transpeptidase, alkaline phosphatase, and Factor VIII antigen activities. The cultured cells can be used in a wide variety of experiments where a model for polarized binding or transport is required. By plating the cells in multi-well plates, receptor and non-receptor binding of both large and small molecules can be conducted. In order to conduct transendothelial cell flux measurements, the cells are grown on porous polycarbonate membrane filters (e.g., from Nucleopore, Pleasanton, CA) . Large pore size filters (5-12 mμ) are used to avoid the possibility of the filter becoming the rate-limiting barrier to molecular flux. The use of these large-pore filters does not permit cell growth under the filter and allows visual inspection of the cell monolayer. Once the cells reach confluency, they are placed in a side-by-side diffusion cell apparatus (e.g., from Crown Glass, Sommerville, NJ) . For flux measurements, the donor chamber of the diffusion cell is pulsed with a test substance, then at various times following the pulse, an aliquot is removed from the receiver chamber for analysis. Radioactive or fluorescently-labelled substances permit reliable quantitation of molecular flux. Monolayer integrity is simultaneously measured by the addition of a non-transportable test substance such as sucrose or inulin and replicates of at least 4 determinations are measured in order to ensure statistical significance. Example 13. Screening Assay for Candidate Compounds which Alter Endogenous Morphogen Levels Candidate compound(s) which may be administered to affect the level of a given morphogen may be found using the following screening assay, in which the level of morphogen production by a cell type which produces measurable levels of the morphogen is determined with and without incubating the cell in culture with the compound, in order to assess the effects of the compound on the cell. This can be accomplished by detection of the morphogen either at the protein or RNA level. A more detailed description also may be found in international application US92/07359 (WO92/05172) . 13.1 Growth of Cells in Culture Cell cultures of kidney, adrenals, urinary bladder, brain, or other organs, may be prepared as described widely in the literature. For example, kidneys may be explanted from neonatal or new born or young or adult rodents (mouse or rat) and used in organ culture as whole or sliced (1-4 mm) tissues. Primary tissue cultures and established cell lines, also derived from kidney, adrenals, urinary, bladder, brain, mammary, or other tissues may be established in multiwell plates (6 well or 24 well) according to conventional cell culture techniques, and are cultured in the absence or presence of serum for a period of time (1-7 days). Cells may be cultured, for example, in Dulbecco's Modified Eagle medium (Gibco, Long Island, NY) containing serum (e.g., fetal calf serum at 1%-10%, Gibco) or in serum-deprived medium, as desired, or in defined medium (e.g., containing insulin, transferrin, glucose, albumin, or other growth factors) . Samples for testing the level of morphogen production includes culture supernatants or cell lysates, collected periodically and evaluated for OP-l production by immunoblot analysis (Sambrook et al., eds., 1989, Molecular Cloning, Cold Spring Harbor Press, Cold Spring Harbor, NY), or a portion of the cell culture itself, collected periodically and used to prepare polyA+ RNA for RNA analysis. To monitor de novo OP-l synthesis, some cultures are labeled according to conventional procedures with an 35 S-methionine/ 35 S-cysteine mixture for 6-24 hours and then evaluated to OP-l synthesis by conventional immunoprecipitation methods. 13.2 Determination of Level of Morphogenic Protein In order to quantitate the production of a morphogenic protein by a cell type, an immunoassay may be performed to detect the morphogen using a polyclonal or monoclonal antibody specific for that protein. For example, OP-l may be detected using a polyclonal antibody specific for OP-l in an ELISA, as follows. 1 μg/100 μl of affinity-purified polyclonal rabbit IgG specific for OP-l is added to each well of a 96-well plate and incubated at 37°C for an hour. The wells are washed four times with 0.167M sodium borate buffer with 0.15 M NaCl (BSB), pH 8.2, containing 0.1% Tween 20. To minimize non-specific binding, the wells are blocked by filling completely with 1% bovine serum albumin (BSA) in BSB and incubating for 1 hour at 37°C. The wells are then washed four times with BSB containing 0.1% Tween 20. A 100 μl aliquot of an appropriate dilution of each of the test samples of cell culture supernatant is added to each well in triplicate and incubated at 37°C for 30 min. After incubation, 100 μl biotinylated rabbit anti-OP-1 serum (stock solution is about 1 mg/ml and diluted 1:400 in BSB containing 1% BSA before use) is added to each well and incubated at 37°C for 30 min. The wells are then washed four times with BSB containing 0.1% Tween 20. 100 μl strepavidin-alkaline (Southern Biotechnology Associates, Inc. Birmingham, Alabama, diluted 1:2000 in BSB containing 0.1% Tween 20 before use) is added to each well and incubated at 37°C for 30 min. The plates are washed four times with 0.5M Tris buffered Saline (TBS), pH 7.2. 50μl substrate (ELISA Amplification System Kit, Life Technologies, Inc., Bethesda, MD) is added to each well incubated at room temperature for 15 min. Then, 50 μl amplifier (from the same amplification system kit) is added and incubated for another 15 min at room temperature. The reaction is stopped by the addition of 50 μl 0.3 M sulphuric acid. The OD at 490 nm of the solution in each well is recorded. To quantitate OP-l in culture media, a OP-l standard curve is performed in parallel with the test samples. Polyclonal antibody may be prepared as follows. Each rabbit is given a primary immunization of 100 ug/500 μl E. coli produced OP-l monomer (amino acids 328-431 in SEQ ID NO:5) in 0.1% SDS mixed with 500 μl Complete Freund's Adjuvant. The antigen is injected subcutaneously at multiple sites on the back and flanks of the animal. The rabbit is boosted after a month in the same manner using incomplete Freund's Adjuvant. Test bleeds are taken from the ear vein seven days later. Two additional boosts and test bleeds are performed at monthly intervals until antibody against OP-l is detected in the serum using an ELISA assay. Then, the rabbit is boosted monthly with 100 μg of antigen and bled (15 ml per bleed) at days seven and ten after boosting. Monoclonal antibody specific for a given morphogen may be prepared as follows. A mouse is given two injections of E. coli produced OP-l monomer. The first injection contains lOOμg of OP-l in complete Freund's adjuvant and is given subcutaneously. The second injection contains 50 μg of OP-l in incomplete adjuvant and is given intraperitoneally. The mouse then receives a total of 230 μg of OP-l (amino acids 307-431 in SEQ ID NO:5) in four intraperitoneal injections at various times over an eight month period. One week prior to fusion, both mice are boosted intraperitoneally with 100 μg of OP-l (307-431) and 30 μg of the N-terminal peptide (Ser 2g3 -Asn 309 -Cys) conjugated through the added cysteine to bovine serum albumin with SMCC crosslinking agent. This boost was repeated five days (IP), four days (IP), three days (IP) and one day (IV) prior to fusion. The mouse spleen cells are then fused to myeloma (e.g., 653) cells at a ratio of 1:1 using PEG 1500 (Boeringer Mannheim) , and the cell fusion is plated and screened for OP-1-specific antibodies using OP-l (307-431) as antigen. The cell fusion and monoclonal screening then are according to standard procedures well described in standard texts widely available in the art. The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. SEQUENCE LISTING (1) GENERAL INFORMATION: (i) APPLICANT: (A) NAME: CREATIVE BIOMOLECULES, INC. (B) STREET: 35 SOUTH STREET (C) CITY: HOPKINTON (D) STATE: MASSACHUSETTS (E) COUNTRY: USA (F) POSTAL CODE (ZIP): 01748 (G) TELEPHONE: 1-508-435-9001 (H) TELEFAX: 1-508-435-0454 (I) TELEX: (ii) TITLE OF INVENTION: MORPHOGEN-INDUCED NERVE REGENERATION AND REPAIR (iii) NUMBER OF SEQUENCES: .33 (iv) CORRESPONDENCE ADDRESS: (A) ADDRESSEE: CREATIVE BIOMOLECULES, INC. (B) STREET: 35 SOUTH STREET (C) CITY: HOPKINTON (D) STATE: MASSACHUSETTS (E) COUNTRY: USA (F) ZIP: 01748 (v) COMPUTER READABLE FORM: (A) MEDIUM TYPE: Floppy disk (B) COMPUTER: IBM PC compatible (C) OPERATING SYSTEM: PC-DOS/MS-DOS (D) SOFTWARE: Patentln Release #1.0, Version #1.25 (viii) ATTORNEY/AGENT INFORMATION: (A) NAME: KELLEY, ROBIN D. (B) REGISTRATION NUMBER: 34,637 (C) REFERENCE/DOCKET NUMBER: CRP-070 (ix) TELECOMMUNICATION INFORMATION: (A) TELEPHONE: 617/248-7000 (B) TELEFAX: 617/248-7100 (2) INFORMATION FOR SEQ ID NO:l: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 97 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..97 (D) OTHER INFORMATION: /label= GENERIC-SEQ1 /note= "WHEREIN EACH XAA INDEPENDENTLY INDICATES ONE OF THE 20 NATURALLY-OCCURING L-ISOMER, A-AMINO ACIDS, OR A DERIVATIVE THEREOF." (xi) SEQUENCE DESCRIPTION: SEQ ID NO:l: Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 1 5 10 15 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Xaa Xaa Xaa Cys Xaa Xaa Xaa 20 25 30 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Cys Xaa Xaa 50 55 60 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 65 70 75 80 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Xaa Cys 85 90 95 Xaa (2) INFORMATION FOR SEQ ID NO:2: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 97 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..97 (D) OTHER INFORMATION: /label= GENERIC-SEQ2 /note= "WHEREIN EACH XAA INDEPENDENTLY INDICATES ONE OF THE 20 NATURALLY OCCURING L-ISOMER A-AMINO ACIDS, OR A DERIVATIVE THEREOF." (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2: Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 1 5 10 15 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Xaa Xaa Xaa Cys Xaa Xaa Xaa 20 25 30 Xaa Xaa Xaa Cys Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Cys Xaa Xaa 50 55 60 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 65 70 75 80 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Xaa Cys 85 90 95 Xaa (2) INFORMATION FOR SEQ ID NO:3: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 97 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..97 (D) OTHER INFORMATION: /label= GENERIC-SEQ3 /note= "WHEREIN EACH XAA IS INDEPENDENTLY SELECTED FROM A GROUP OF ONE OR MORE SPECIFIED AMINO ACIDS AS DEFINED IN THE SPECIFICATION." - Ill - (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3: Leu Tyr Val Xaa Phe Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa Xaa Ala 1 5 10 15 Pro Xaa Gly Xaa Xaa Ala Xaa Tyr Cys Xaa Gly Xaa Cys Xaa Xaa Pro 20 25 30 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asn His Ala Xaa Xaa Xaa Xaa Leu 35 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Cys Xaa Pro 50 55 60 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Leu Xaa Xaa Xaa Xaa Xaa Xaa Xaa 65 70 75 80 Val Xaa Leu Xaa Xaa Xaa Xaa Xaa Met Xaa Val Xaa Xaa Cys Gly Cys 85 90 95 Xaa (2) INFORMATION FOR SEQ ID NO:4: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /label= GENERIC-SEQ4 /note= "WHEREIN EACH XAA IS INDEPENDENTLY SELECTED FROM A GROUP OF ONE OR MORE SPECIFIED AMINO ACIDS AS DEFINED IN THE SPECIFICATION." ( i) SEQUENCE DESCRIPTION: SEQ ID NO:4: Cys Xaa Xaa Xaa Xaa Leu Tyr Val Xaa Phe Xaa Xaa Xaa Gly Trp Xaa 1 5 10 15 Xaa Trp Xaa Xaa Ala Pro Xaa Gly Xaa Xaa Ala Xaa Tyr Cys Xaa Gly 20 25 30 Xaa Cys Xaa Xaa Pro Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asn His Ala 35 40 45 Xaa Xaa Xaa Xaa Leu Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55 60 Xaa Cys Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Leu Xaa Xaa 65 70 75 80 Xaa Xaa Xaa Xaa Xaa Val Xaa Leu Xaa Xaa Xaa Xaa Xaa Met Xaa Val 85 90 95 Xaa Xaa Cys Gly Cys Xaa 100 (2) INFORMATION FOR SEQ ID NO:5: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 139 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein ( i) ORIGINAL SOURCE: (A) ORGANISM: Homo sapiens (F) TISSUE TYPE: HIPPOCAMPUS (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..139 (D) OTHER INFORMATION: /label= hOPl-MATURE (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5: Ser Thr Gly Ser Lys Gin Arg Ser Gin Asn Arg Ser Lys Thr Pro Lys 1 5 10 15 Asn Gin Glu Ala Leu Arg Met Ala Asn Val Ala Glu Asn Ser Ser Ser 20 25 30 Asp Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr Val Ser Phe Arg 35 40 45 Asp Leu Gly Trp Gin Asp Trp He He Ala Pro Glu Gly Tyr Ala Ala 50 55 60 Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser Tyr Met Asn 65 70 75 80 Ala Thr Asn His Ala He Val Gin Thr Leu Val His Phe He Asn Pro 85 90 95 Glu Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin Leu Asn Ala He 100 105 110 Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn Val He Leu Lys Lys Tyr 115 120 125 Arg Asn Met Val Val Arg Ala Cys Gly Cys His 130 135 (2) INFORMATION FOR SEQ ID NO:6: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 139 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: MURIDAE (F) TISSUE TYPE: EMBRYO (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..139 (D) OTHER INFORMATION: /label= MOP1-MATURE ( i) SEQUENCE DESCRIPTION: SEQ ID NO:6: Ser Thr Gly Gly Lys Gin Arg Ser Gin Asn Arg Ser Lys Thr Pro Lys 1 5 10 15 Asn Gin Glu Ala Leu Arg Met Ala Ser Val Ala Glu Asn Ser Ser Ser 20 25 30 Asp Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr Val Ser Phe Arg 35 40 45 Asp Leu Gly Trp Gin Asp Trp He He Ala Pro Glu Gly Tyr Ala Ala 50 55 60 Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser Tyr Met Asn 65 70 75 80 Ala Thr Asn His Ala He Val Gin Thr Leu Val His Phe He Asn Pro 85 90 95 Asp Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin Leu Asn Ala He 100 105 110 Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn Val He Leu Lys Lys Tyr 115 120 125 Arg Asn Met Val Val Arg Ala Cys Gly Cys His 130 135 (2) INFORMATION FOR SEQ ID NO:7: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 139 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (F) TISSUE TYPE: HIPPOCAMPUS (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..139 (D) OTHER INFORMATION: /label= H0P2-MATURE (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7: Ala Val Arg Pro Leu Arg Arg Arg Gin Pro Lys Lys Ser Asn Glu Leu 1 5 10 15 Pro Gin Ala Asn Arg Leu Pro Gly He Phe Asp Asp Val His Gly Ser 20 25 30 His Gly Arg Gin Val Cys Arg Arg His Glu Leu Tyr Val Ser Phe Gin 35 40 45 Asp Leu Gly Trp Leu Asp Trp Val He Ala Pro Gin Gly Tyr Ser Ala 50 55 60 Tyr Tyr Cys Glu Gly Glu Cys Ser Phe Pro Leu Asp Ser Cys Met Asn 65 70 75 80 Ala Thr Asn His Ala He Leu Gin Ser Leu Val His Leu Met Lys Pro 85 90 95 Asn Ala Val Pro Lys Ala Cys Cys Ala Pro Thr Lys Leu Ser Ala Thr 100 105 110 Ser Val Leu Tyr Tyr Asp Ser Ser Asn Asn Val He Leu Arg Lys His 115 120 125 Arg Asn Met Val Val Lys Ala Cys Gly Cys His 130 135 (2) INFORMATION FOR SEQ ID NO:8: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 139 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: MURIDAE (F) TISSUE TYPE: EMBRYO (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..139 (D) OTHER INFORMATION: /label= M0P2-MATURE (xi) SEQUENCE DESCRIPTION: SEQ ID N0:8: Ala Ala Arg Pro Leu Lys Arg Arg Gin Pro Lys Lys Thr Asn Glu Leu 1 5 10 15 Pro His Pro Asn Lys Leu Pro Gly He Phe Asp Asp Gly His Gly Ser 20 25 30 Arg Gly Arg Glu Val Cys Arg Arg His Glu Leu Tyr Val Ser Phe Arg 35 40 45 Asp Leu Gly Trp Leu Asp Trp Val He Ala Pro Gin Gly Tyr Ser Ala 50 55 60 Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asp Ser Cys Met Asn 65 70 75 80 Ala Thr Asn His Ala He Leu Gin Ser Leu Val His Leu Met Lys Pro 85 90 95 Asp Val Val Pro Lys Ala Cys Cys Ala Pro Thr Lys Leu Ser Ala Thr 100 105 110 Ser Val Leu Tyr Tyr Asp Ser Ser Asn Asn Val He Leu Arg Lys His 115 120 125 Arg Asn Met Val Val Lys Ala Cys Gly Cys His 130 135 (2) INFORMATION FOR SEQ ID NO:9: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 101 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: bovinae (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..101 (D) OTHER INFORMATION: /label= CBMP-2A-FX ( i) SEQUENCE DESCRIPTION: SEQ ID NO:9: Cys Lys Arg His Pro Leu Tyr Val Asp Phe Ser Asp Val Gly Trp Asn 1 5 10 15 Asp Trp He Val Ala Pro Pro Gly Tyr His Ala Phe Tyr Cys His Gly 20 25 30 Glu Cys Pro Phe Pro Leu Ala Asp His Leu Asn Ser Thr Asn His Ala 35 40 45 He Val Gin Thr Leu Val Asn Ser Val Asn Ser Lys He Pro Lys Ala 50 55 60 Cys Cys Val Pro Thr Glu Leu Ser Ala He Ser Met Leu Tyr Leu Asp 65 70 75 80 Glu Asn Glu Lys Val Val Leu Lys Asn Tyr Gin Asp Met Val Val Glu 85 90 95 Gly Cys Gly Cys Arg 100 (2) INFORMATION FOR SEQ ID NO:10: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 101 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (F) TISSUE TYPE: hippocampus (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..101 (D) OTHER INFORMATION: /label= CBMP-2B-FX (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10: Cys Arg Arg His Ser Leu Tyr Val Asp Phe Ser Asp Val Gly Trp Asn 1 5 10 15 Asp Trp He Val Ala Pro Pro Gly Tyr Gin Ala Phe Tyr Cys His Gly 20 25 30 Asp Cys Pro Phe Pro Leu Ala Asp His Leu Asn Ser Thr Asn His Ala 35 40 45 He Val Gin Thr Leu Val Asn Ser Val Asn Ser Ser He Pro Lys Ala 50 55 60 Cys Cys Val Pro Thr Glu Leu Ser Ala He Ser Met Leu Tyr Leu Asp 65 70 75 80 Glu Tyr Asp Lys Val Val Leu Lys Asn Tyr Gin Glu Met Val Val Glu 85 90 95 Gly Cys Gly Cys Arg 100 (2) INFORMATION FOR SEQ ID NO:11: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: DROSOPHILA MELANOGASTER (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..101 (D) OTHER INFORMATION: /label= DPP-FX (xi) SEQUENCE DESCRIPTION: SEQ ID NO:11: Cys Arg Arg His Ser Leu Tyr Val Asp Phe Ser Asp Val Gly Trp Asp 1 5 10 15 Asp Trp He Val Ala Pro Leu Gly Tyr Asp Ala Tyr Tyr Cys His Gly 20 25 30 Lys Cys Pro Phe Pro Leu Ala Asp His Phe Asn Ser Thr Asn His Ala 35 40 45 Val Val Gin Thr Leu Val Asn Asn Asn Asn Pro Gly Lys Val Pro Lys 50 55 60 Ala Cys Cys Val Pro Thr Gin Leu Asp Ser Val Ala Met Leu Tyr Leu 65 70 75 80 Asn Asp Gin Ser Thr Val Val Leu Lys Asn Tyr Gin Glu Met Thr Val 85 90 95 Val Gly Cys Gly Cys Arg 100 (2) INFORMATION FOR SEQ ID NO:12: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: XENOPUS (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /label= VGL-FX (xi) SEQUENCE DESCRIPTION: SEQ ID NO:12; Cys Lys Lys Arg His Leu Tyr Val Glu Phe Lys Asp Val Gly Trp Gin 1 5 10 15 Asn Trp Val He Ala Pro Gin Gly Tyr Met Ala Asn Tyr Cys Tyr Gly 20 25 30 Glu Cys Pro Tyr Pro Leu Thr Glu He Leu Asn Gly Ser Asn His Ala 35 40 45 He Leu Gin Thr Leu Val His Ser He Glu Pro Glu Asp He Pro Leu 50 55 60 Pro Cys Cys Val Pro Thr Lys Met Ser Pro He Ser Met Leu Phe Tyr 65 70 75 80 Asp Asn Asn Asp Asn Val Val Leu Arg His Tyr Glu Asn Met Ala Val 85 90 95 Asp Glu Cys Gly Cys Arg 100 (2) INFORMATION FOR SEQ ID NO:13: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: MURIDAE (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /label= VGR-l-FX (xi) SEQUENCE DESCRIPTION: SEQ ID NO:13: Cys Lys Lys His Glu Leu Tyr Val Ser Phe Gin Asp Val Gly Trp Gin 1 5 10 15 Asp Trp He He Ala Pro Lys Gly Tyr Ala Ala Asn Tyr Cys Asp Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His Ala 35 40 45 He Val Gin Thr Leu Val His Val Met Asn Pro Glu Tyr Val Pro Lys 50 55 60 Pro Cys Cys Ala Pro Thr Lys Val Asn Ala He Ser Val Leu Tyr Phe 65 70 75 80 Asp Asp Asn Ser Asn Val He Leu Lys Lys Tyr Arg Asn Met Val Val 85 90 95 Arg Ala Cys Gly Cys His 100 (2) INFORMATION FOR SEQ ID NO:14: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 106 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (iii) HYPOTHETICAL: NO (iv) ANTI-SENSE: NO (vi) ORIGINAL SOURCE: (A) ORGANISM: Homo sapiens (F) TISSUE TYPE: brain (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..106 (D) OTHER INFORMATION: /note= "GDF-1 (fx)" (xi) SEQUENCE DESCRIPTION: SEQ ID N0:Ϊ4: Cys Arg Ala Arg Arg Leu Tyr Val Ser Phe Arg Glu Val Gly Trp His 1 5 10 15 Arg Trp Val He Ala Pro Arg Gly Phe Leu Ala Asn Tyr Cys Gin Gly 20 25 30 Gin Cys Ala Leu Pro Val Ala Leu Ser Gly Ser Gly Gly Pro Pro Ala 35 40 45 Leu Asn His Ala Val Leu Arg Ala Leu Met His Ala Ala Ala Pro Gly 50 55 60 Ala Ala Asp Leu Pro Cys Cys Val Pro Ala Arg Leu Ser Pro He Ser 65 70 75 80 Val Leu Phe Phe Asp Asn Ser Asp Asn Val Val Leu Arg Gin Tyr Glu 85 90 95 Asp Met Val Val Asp Glu Cys Gly Cys Arg 100 105 (2) INFORMATION FOR SEQ ID NO:15: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 5 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO:15: Cys Xaa Xaa Xaa Xaa 1 5 (2) INFORMATION FOR SEQ ID NO:16: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1822 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (iii) HYPOTHETICAL: NO (iv) ANTI-SENSE: NO (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (F) TISSUE TYPE: HIPPOCAMPUS (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 49..1341 (C) IDENTIFICATION METHOD: experimental (D) OTHER INFORMATION: /function= "OSTEOGENIC PROTEIN" /product= "OP1" /evidence EXPERIMENTAL /standard name= "OP1" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:16: GGTGCGGGCC CGGAGCCCGG AGCCCGGGTA GCGCGTAGAG CCGGCGCG ATG CAC GTG 57 Met His Val 1 CGC TCA CTG CGA GCT GCG GCG CCG CAC AGC TTC GTG GCG CTC TGG GCA 105 Arg Ser Leu Arg Ala Ala Ala Pro His Ser Phe Val Ala Leu Trp Ala 5 10 15 CCC CTG TTC CTG CTG CGC TCC GCC CTG GCC GAC TTC AGC CTG GAC AAC 153 Pro Leu Phe Leu Leu Arg Ser Ala Leu Ala Asp Phe Ser Leu Asp Asn 20 25 30 35 GAG GTG CAC TCG AGC TTC ATC CAC CGG CGC CTC CGC AGC CAG GAG CGG 201 Glu Val His Ser Ser Phe He His Arg Arg Leu Arg Ser Gin Glu Arg 40 45 50 CGG GAG ATG CAG CGC GAG ATC CTC TCC ATT TTG GGC TTG CCC CAC CGC 249 Arg Glu Met Gin Arg Glu He Leu Ser He Leu Gly Leu Pro His Arg 55 60 65 CCG CGC CCG CAC CTC CAG GGC AAG CAC AAC TCG GCA CCC ATG TTC ATG 297 Pro Arg Pro His Leu Gin Gly Lys His Asn Ser Ala Pro Met Phe Met 70 75 80 CTG GAC CTG TAC AAC GCC ATG GCG GTG GAG GAG GGC GGC GGG CCC GGC 345 Leu Asp Leu Tyr Asn Ala Met Ala Val Glu Glu Gly Gly Gly Pro Gly 85 90 95 GGC CAG GGC TTC TCC TAC CCC TAC AAG GCC GTC TTC AGT ACC CAG GGC 393 Gly Gin Gly Phe Ser Tyr Pro Tyr Lys Ala Val Phe Ser Thr Gin Gly 100 105 110 115 CCC CCT CTG GCC AGC CTG CAA GAT AGC CAT TTC CTC ACC GAC GCC GAC 441 Pro Pro Leu Ala Ser Leu Gin Asp Ser His Phe Leu Thr Asp Ala Asp 120 125 130 ATG GTC ATG AGC TTC GTC AAC CTC GTG GAA CAT GAC AAG GAA TTC TTC 489 Met Val Met Ser Phe Val Asn Leu Val Glu His Asp Lys Glu Phe Phe 135 140 145 CAC CCA CGC TAC CAC CAT CGA GAG TTC CGG TTT GAT CTT TCC AAG ATC 537 His Pro Arg Tyr His His Arg Glu Phe Arg Phe Asp Leu Ser Lys He 150 155 160 CCA GAA GGG GAA GCT GTC ACG GCA GCC GAA TTC CGG ATC TAC AAG GAC 585 Pro Glu Gly Glu Ala Val Thr Ala Ala Glu Phe Arg He Tyr Lys Asp 165 170 175 TAC ATC CGG GAA CGC TTC GAC AAT GAG ACG TTC CGG ATC AGC GTT TAT 633 Tyr He Arg Glu Arg Phe Asp Asn Glu Thr Phe Arg He Ser Val Tyr 180 185 190 195 CAG GTG CTC CAG GAG CAC TTG GGC AGG GAA TCG GAT CTC TTC CTG CTC 681 Gin Val Leu Gin Glu His Leu Gly Arg Glu Ser Asp Leu Phe Leu Leu 200 205 210 GAC AGC CGT ACC CTC TGG GCC TCG GAG GAG GGC TGG CTG GTG TTT GAC 729 Asp Ser Arg Thr Leu Trp Ala Ser Glu Glu Gly Trp Leu Val Phe Asp 215 220 225 ATC ACA GCC ACC AGC AAC CAC TGG GTG GTC AAT CCG CGG CAC AAC CTG 777 He Thr Ala Thr Ser Asn His Trp Val Val Asn Pro Arg His Asn Leu 230 235 240 GGC CTG CAG CTC TCG GTG GAG ACG CTG GAT GGG CAG AGC ATC AAC CCC 825 Gly Leu Gin Leu Ser Val Glu Thr Leu Asp Gly Gin Ser He Asn Pro 245 250 255 AAG TTG GCG GGC CTG ATT GGG CGG CAC GGG CCC CAG AAC AAG CAG CCC 873 Lys Leu Ala Gly Leu He Gly Arg His Gly Pro Gin Asn Lys Gin Pro 260 265 270 275 TTC ATG GTG GCT TTC TTC AAG GCC ACG GAG GTC CAC TTC CGC AGC ATC 921 Phe Met Val Ala Phe Phe Lys Ala Thr Glu Val His Phe Arg Ser He 280 285 290 CGG TCC ACG GGG AGC AAA CAG CGC AGC CAG AAC CGC TCC AAG ACG CCC 969 Arg Ser Thr Gly Ser Lys Gin Arg Ser Gin Asn Arg Ser Lys Thr Pro 295 300 305 AAG AAC CAG GAA GCC CTG CGG ATG GCC AAC GTG GCA GAG AAC AGC AGC 1017 Lys Asn Gin Glu Ala Leu Arg Met Ala Asn Val Ala Glu Asn Ser Ser 310 315 320 AGC GAC CAG AGG CAG GCC TGT AAG AAG CAC GAG CTG TAT GTC AGC TTC 1065 Ser Asp Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr Val Ser Phe 325 * 330 335 CGA GAC CTG GGC TGG CAG GAC TGG ATC ATC GCG CCT GAA GGC TAC GCC 1113 Arg Asp Leu Gly Trp Gin Asp Trp He He Ala Pro Glu Gly Tyr Ala 340 345 350 355 GCC TAC TAC TGT GAG GGG GAG TGT GCC TTC CCT CTG AAC TCC TAC ATG 1161 Ala Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser Tyr Met 360 365 370 AAC GCC ACC AAC CAC GCC ATC GTG CAG ACG CTG GTC CAC TTC ATC AAC 1209 Asn Ala Thr Asn His Ala He Val Gin Thr Leu Val His Phe He Asn 375 380 385 CCG GAA ACG GTG CCC AAG CCC TGC TGT GCG CCC ACG CAG CTC AAT GCC 1257 Pro Glu Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin Leu Asn Ala 390 395 400 ATC TCC GTC CTC TAC TTC GAT GAC AGC TCC AAC GTC ATC CTG AAG AAA 1305 He Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn Val He Leu Lys Lys 405 410 415 TAC AGA AAC ATG GTG GTC CGG GCC TGT GGC TGC CAC TAGCTCCTCC 1351 Tyr Arg Asn Met Val Val Arg Ala Cys Gly Cys His 420 425 430 GAGAATTCAG ACCCTTTGGG GCCAAGTTTT TCTGGATCCT CCATTGCTCG CCTTGGCCAG 1411 GAACCAGCAG ACCAACTGCC TTTTGTGAGA CCTTCCCCTC CCTATCCCCA ACTTTAAAGG 1471 TGTGAGAGTA TTAGGAAACA TGAGCAGCAT ATGGCTTTTG ATCAGTTTTT CAGTGGCAGC 1531 ATCCAATGAA CAAGATCCTA CAAGCTGTGC AGGCAAAACC TAGCAGGAAA AAAAAACAAC 1591 GCATAAAGAA AAATGGCCGG GCCAGGTCAT TGGCTGGGAA GTCTCAGCCA TGCACGGACT 1651 CGTTTCCAGA GGTAATTATG AGCGCCTACC AGCCAGGCCA CCCAGCCGTG GGAGGAAGGG 1711 GGCGTGGCAA GGGGTGGGCA CATTGGTGTC TGTGCGAAAG GAAAATTGAC CCGGAAGTTC 1771 CTGTAATAAA TGTCACAATA AAACGAATGA ATGAAAAAAA AAAAAAAAAA A 1822 (2) INFORMATION FOR SEQ ID NO:17: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 431 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein ( i) SEQUENCE DESCRIPTION: SEQ ID NO:17: Met His Val Arg Ser Leu Arg Ala Ala Ala Pro His Ser Phe Val Ala 1 5 10 15 Leu Trp Ala Pro Leu Phe Leu Leu Arg Ser Ala Leu Ala Asp Phe Ser 20 25 30 Leu Asp Asn Glu Val His Ser Ser Phe He His Arg Arg Leu Arg Ser 35 40 45 Gin Glu Arg Arg Glu Met Gin Arg Glu He Leu Ser He Leu Gly Leu 50 55 60 Pro His Arg Pro Arg Pro His Leu Gin Gly Lys His Asn Ser Ala Pro 65 70 75 80 Met Phe Met Leu Asp Leu Tyr Asn Ala Met Ala Val Glu Glu Gly Gly 85 90 95 Gly Pro Gly Gly Gin Gly Phe Ser Tyr Pro Tyr Lys Ala Val Phe Ser 100 105 110 Thr Gin Gly Pro Pro Leu Ala Ser Leu Gin Asp Ser His Phe Leu Thr 115 120 125 Asp Ala Asp Met Val Met Ser Phe Val Asn Leu Val Glu His Asp Lys 130 135 140 Glu Phe Phe His Pro Arg Tyr His His Arg Glu Phe Arg Phe Asp Leu 145 150 155 160 Ser Lys He Pro Glu Gly Glu Ala Val Thr Ala Ala Glu Phe Arg He 165 170 175 Tyr Lys Asp Tyr He Arg Glu Arg Phe Asp Asn Glu Thr Phe Arg He 180 185 190 Ser Val Tyr Gin Val Leu Gin Glu His Leu Gly Arg Glu Ser Asp Leu 195 200 205 Phe Leu Leu Asp Ser Arg Thr Leu Trp Ala Ser Glu Glu Gly Trp Leu 210 215 220 Val Phe Asp He Thr Ala Thr Ser Asn His Trp Val Val Asn Pro Arg 225 230 235 240 His Asn Leu Gly Leu Gin Leu Ser Val Glu Thr Leu Asp Gly Gin Ser 245 250 255 He Asn Pro Lys Leu Ala Gly Leu He Gly Arg His Gly Pro Gin Asn 260 265 270 Lys Gin Pro Phe Met Val Ala Phe Phe Lys Ala Thr Glu Val His Phe 275 280 285 Arg Ser He Arg Ser Thr Gly Ser Lys Gin Arg Ser Gin Asn Arg Ser 290 295 300 Lys Thr Pro Lys Asn Gin Glu Ala Leu Arg Met Ala Asn Val Ala Glu 305 310 315 320 Asn Ser Ser Ser Asp Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr 325 330 335 Val Ser Phe Arg Asp Leu Gly Trp Gin Asp Trp He He Ala Pro Glu 340 345 350 Gly Tyr Ala Ala Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn 355 360 365 Ser Tyr Met Asn Ala Thr Asn His Ala He Val Gin Thr Leu Val His 370 375 380 Phe He Asn Pro Glu Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin 385 390 395 400 Leu Asn Ala He Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn Val He 405 410 415 Leu Lys Lys Tyr Arg Asn Met Val Val Arg Ala Cys Gly Cys His 420 425 430 (2) INFORMATION FOR SEQ ID NO:18: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1873 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (iii) HYPOTHETICAL: NO (iv) ANTI-SENSE: NO (vi) ORIGINAL SOURCE: (A) ORGANISM: MURIDAE (F) TISSUE TYPE: EMBRYO (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 104..1393 (D) OTHER INFORMATION: /function= "OSTEOGENIC PROTEIN" /product- "MOPl" /note= "MOPl (CDNA)" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:18: CTGCAGCAAG TGACCTCGGG TCGTGGACCG CTGCCCTGCC CCCTCCGCTG CCACCTGGGG 60 CGGCGCGGGC CCGGTGCCCC GGATCGCGCG TAGAGCCGGC GCG ATG CAC GTG CGC 115 Met His Val Arg 1 TCG CTG CGC GCT GCG GCG CCA CAC AGC TTC GTG GCG CTC TGG GCG CCT 163 Ser Leu Arg Ala Ala Ala Pro His Ser Phe Val Ala Leu Trp Ala Pro 5 10 15 20 CTG TTC TTG CTG CGC TCC GCC CTG GCC GAT TTC AGC CTG GAC AAC GAG 211 Leu Phe Leu Leu Arg Ser Ala Leu Ala Asp Phe Ser Leu Asp Asn Glu 25 30 35 GTG CAC TCC AGC TTC ATC CAC CGG CGC CTC CGC AGC CAG GAG CGG CGG 259 Val His Ser Ser Phe He His Arg Arg Leu Arg Ser Gin Glu Arg Arg 40 45 50 GAG ATG CAG CGG GAG ATC CTG TCC ATC TTA GGG TTG CCC CAT CGC CCG 307 Glu Met Gin Arg Glu He Leu Ser He Leu Gly Leu Pro His Arg Pro 55 60 65 CGC CCG CAC CTC CAG GGA AAG CAT AAT TCG GCG CCC ATG TTC ATG TTG 355 Arg Pro His Leu Gin Gly Lys His Asn Ser Ala Pro Met Phe Met Leu 70 75 80 GAC CTG TAC AAC GCC ATG GCG GTG GAG GAG AGC GGG CCG GAC GGA CAG 403 Asp Leu Tyr Asn Ala Met Ala Val Glu Glu Ser Gly Pro Asp Gly Gin 85 90 95 100 GGC TTC TCC TAC CCC TAC AAG GCC GTC TTC AGT ACC CAG GGC CCC CCT 451 Gly Phe Ser Tyr Pro Tyr Lys Ala Val Phe Ser Thr Gin Gly Pro Pro 105 110 115 TTA GCC AGC CTG CAG GAC AGC CAT TTC CTC ACT GAC GCC GAC ATG GTC 499 Leu Ala Ser Leu Gin Asp Ser His Phe Leu Thr Asp Ala Asp Met Val 120 125 130 ATG AGC TTC GTC AAC CTA GTG GAA CAT GAC AAA GAA TTC TTC CAC CCT 547 Met Ser Phe Val Asn Leu Val Glu His Asp Lys Glu Phe Phe His Pro 135 140 145 CGA TAC CAC CAT CGG GAG TTC CGG TTT GAT CTT TCC AAG ATC CCC GAG 595 Arg Tyr His His Arg Glu Phe Arg Phe Asp Leu Ser Lys He Pro Glu 150 155 160 GGC GAA CGG GTG ACC GCA GCC GAA TTC AGG ATC TAT AAG GAC TAC ATC 643 Gly Glu Arg Val Thr Ala Ala Glu Phe Arg He Tyr Lys Asp Tyr He 165 170 175 180 CGG GAG CGA TTT GAC AAC GAG ACC TTC CAG ATC ACA GTC TAT CAG GTG 691 Arg Glu Arg Phe Asp Asn Glu Thr Phe Gin He Thr Val Tyr Gin Val 185 190 195 CTC CAG GAG CAC TCA GGC AGG GAG TCG GAC CTC TTC TTG CTG GAC AGC 739 Leu Gin Glu His Ser Gly Arg Glu Ser Asp Leu Phe Leu Leu Asp Ser 200 205 210 CGC ACC ATC TGG GCT TCT GAG GAG GGC TGG TTG GTG TTT GAT ATC ACA 787 Arg Thr He Trp Ala Ser Glu Glu Gly Trp Leu Val Phe Asp He Thr 215 220 225 GCC ACC AGC AAC CAC TGG GTG GTC AAC CCT CGG CAC AAC CTG GGC TTA 835 Ala Thr Ser Asn His Trp Val Val Asn Pro Arg His Asn Leu Gly Leu 230 235 240 CAG CTC TCT GTG GAG ACC CTG GAT GGG CAG AGC ATC AAC CCC AAG TTG 883 Gin Leu Ser Val Glu Thr Leu Asp Gly Gin Ser He Asn Pro Lys Leu 245 250 255 260 GCA GGC CTG ATT GGA CGG CAT GGA CCC CAG AAC AAG CAA CCC TTC ATG 931 Ala Gly Leu He Gly Arg His Gly Pro Gin Asn Lys Gin Pro Phe Met 265 270 275 GTG GCC TTC TTC AAG GCC ACG GAA GTC CAT CTC CGT AGT ATC CGG TCC 979 Val Ala Phe Phe Lys Ala Thr Glu Val His Leu Arg Ser He Arg Ser 280 285 290 ACG GGG GGC AAG CAG CGC AGC CAG AAT CGC TCC AAG ACG CCA AAG AAC 1027 Thr Gly Gly Lys Gin Arg Ser Gin Asn Arg Ser Lys Thr Pro Lys Asn 295 300 305 CAA GAG GCC CTG AGG ATG GCC AGT GTG GCA GAA AAC AGC AGC AGT GAC 1075 Gin Glu Ala Leu Arg Met Ala Ser Val Ala Glu Asn Ser Ser Ser Asp 310 315 320 CAG AGG CAG GCC TGC AAG AAA CAT GAG CTG TAC GTC AGC TTC CGA GAC 1123 Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr Val Ser Phe Arg Asp 325 330 335 340 CTT GGC TGG CAG GAC TGG ATC ATT GCA CCT GAA GGC TAT GCT GCC TAC 1171 Leu Gly Trp Gin Asp Trp He He Ala Pro Glu Gly Tyr Ala Ala Tyr 345 350 355 TAC TGT GAG GGA GAG TGC GCC TTC CCT CTG AAC TCC TAC ATG AAC GCC 1219 Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser Tyr Met Asn Ala 360 365 370 ACC AAC CAC GCC ATC GTC CAG ACA CTG GTT CAC TTC ATC AAC CCA GAC 1267 Thr Asn His Ala He Val Gin Thr Leu Val His Phe He Asn Pro Asp 375 380 385 ACA GTA CCC AAG CCC TGC TGT GCG CCC ACC CAG CTC AAC GCC ATC TCT 1315 Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin Leu Asn Ala He Ser 390 395 400 GTC CTC TAC TTC GAC GAC AGC TCT AAT GTC GAC CTG AAG AAG TAC AGA 1363 Val Leu Tyr Phe Asp Asp Ser Ser Asn Val Asp Leu Lys Lys Tyr Arg 405 410 415 420 AAC ATG GTG GTC CGG GCC TGT GGC TGC CAC TAGCTCTTCC TGAGACCCTG 1413 Asn Met Val Val Arg Ala Cys Gly Cys His 425 430 ACCTTTGCGG GGCCACACCT TTCCAAATCT TCGATGTCTC ACCATCTAAG TCTCTCACTG 1473 CCCACCTTGG CGAGGAGAAC AGACCAACCT CTCCTGAGCC TTCCCTCACC TCCCAACCGG 1533 AAGCATGTAA GGGTTCCAGA AACCTGAGCG TGCAGCAGCT GATGAGCGCC CTTTCCTTCT 1593 GGCACGTGAC GGACAAGATC CTACCAGCTA CCACAGCAAA CGCCTAAGAG CAGGAAAAAT 1653 GTCTGCCAGG AAAGTGTCCA GTGTCCACAT GGCCCCTGGC GCTCTGAGTC TTTGAGGAGT 1713 AATCGCAAGC CTCGTTCAGC TGCAGCAGAA GGAAGGGCTT AGCCAGGGTG GGCGCTGGCG 1773 TCTGTGTTGA AGGGAAACCA AGCAGAAGCC ACTGTAATGA TATGTCACAA TAAAACCCAT 1833 GAATGAAAAA AAAAAAAAAA AAAAAAAAAA AAAAGAATTC 1873 (2) INFORMATION FOR SEQ ID NO:19: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 430 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (Xi) SEQUENCE DESCRIPTION: SEQ ID NO:19: Met His Val Arg Ser Leu Arg Ala Ala Ala Pro His Ser Phe Val Ala 1 5 10 15 Leu Trp Ala Pro Leu Phe Leu Leu Arg Ser Ala Leu Ala Asp Phe Ser 20 25 30 Leu Asp Asn Glu Val His Ser Ser Phe He His Arg Arg Leu Arg Ser 35 40 45 Gin Glu Arg Arg Glu Met Gin Arg Glu He Leu Ser He Leu Gly Leu 50 55 60 Pro His Arg Pro Arg Pro His Leu Gin Gly Lys His Asn Ser Ala Pro 65 70 75 80 Met Phe Met Leu Asp Leu Tyr Asn Ala Met Ala Val Glu Glu Ser Gly 85 90 95 Pro Asp Gly Gin Gly Phe Ser Tyr Pro Tyr Lys Ala Val Phe Ser Thr 100 105 110 Gin Gly Pro Pro Leu Ala Ser Leu Gin Asp Ser His Phe Leu Thr Asp 115 120 125 Ala Asp Met Val Met Ser Phe Val Asn Leu Val Glu His Asp Lys Glu 130 135 140 Phe Phe His Pro Arg Tyr His His Arg Glu Phe Arg Phe Asp Leu Ser 145 150 155 160 Lys He Pro Glu Gly Glu Arg Val Thr Ala Ala Glu Phe Arg He Tyr 165 170 175 Lys Asp Tyr He Arg Glu Arg Phe Asp Asn Glu Thr Phe Gin He Thr 180 185 190 Val Tyr Gin Val Leu Gin Glu His Ser Gly Arg Glu Ser Asp Leu Phe 195 200 205 Leu Leu Asp Ser Arg Thr He Trp Ala Ser Glu Glu Gly Trp Leu Val 210 215 220 Phe Asp He Thr Ala Thr Ser Asn His Trp Val Val Asn Pro Arg His 225 230 235 240 Asn Leu Gly Leu Gin Leu Ser Val Glu Thr Leu Asp Gly Gin Ser He 245 250 255 Asn Pro Lys Leu Ala Gly Leu He Gly Arg His Gly Pro Gin Asn Lys 260 265 270 Gin Pro Phe Met Val Ala Phe Phe Lys Ala Thr Glu Val His Leu Arg 275 280 285 Ser He Arg Ser Thr Gly Gly Lys Gin Arg Ser Gin Asn Arg Ser Lys 290 295 300 Thr Pro Lys Asn Gin Glu Ala Leu Arg Met Ala Ser Val Ala Glu Asn 305 310 315 320 Ser Ser Ser Asp Gin Arg Gin Ala Cys Lys Lys His Glu Leu Tyr Val 325 330 335 Ser Phe Arg Asp Leu Gly Trp Gin Asp Trp He He Ala Pro Glu Gly 340 345 350 Tyr Ala Ala Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser 355 360 365 Tyr Met Asn Ala Thr Asn His Ala He Val Gin Thr Leu Val His Phe 370 375 380 He Asn Pro Asp Thr Val Pro Lys Pro Cys Cys Ala Pro Thr Gin Leu 385 390 395 400 Asn Ala He Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn Val Asp Leu 405 410 415 Lys Lys Tyr Arg Asn Met Val Val Arg Ala Cys Gly Cys His 420 425 430 (2) INFORMATION FOR SEQ ID NO:20: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1723 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (vi) ORIGINAL SOURCE: (A) ORGANISM: Homo sapiens (F) TISSUE TYPE: HIPPOCAMPUS (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 490..1696 (D) OTHER INFORMATION: /function- "OSTEOGENIC PROTEIN" /product- "hOP2-PP" /note- "hOP2 (cDNA)" (xi) SEQUENCE DESCRIPTION: SEQ ID N0:20: GGCGCCGGCA GAGCAGGAGT GGCTGGAGGA GCTGTGGTTG GAGCAGGAGG TGGCACGGCA 60 GGGCTGGAGG GCTCCCTATG AGTGGCGGAG ACGGCCCAGG AGGCGCTGGA GCAACAGCTC 120 CCACACCGCA CCAAGCGGTG GCTGCAGGAG CTCGCCCATC GCCCCTGCGC TGCTCGGACC 180 GCGGCCACAG CCGGACTGGC GGGTACGGCG GCGACAGAGG CATTGGCCGA GAGTCCCAGT 240 CCGCAGAGTA GCCCCGGCCT CGAGGCGGTG GCGTCCCGGT CCTCTCCGTC CAGGAGCCAG 300 GACAGGTGTC GCGCGGCGGG GCTCCAGGGA CCGCGCCTGA GGCCGGCTGC CCGCCCGTCC 360 CGCCCCGCCC CGCCGCCCGC CGCCCGCCGA GCCCAGCCTC CTTGCCGTCG GGGCGTCCCC 420 AGGCCCTGGG TCGGCCGCGG AGCCGATGCG CGCCCGCTGA GCGCCCCAGC TGAGCGCCCC 480 CGGCCTGCC ATG ACC GCG CTC CCC GGC CCG CTC TGG CTC CTG GGC CTG 528 Met Thr Ala Leu Pro Gly Pro Leu Trp Leu Leu Gly Leu 1 5 10 GCG CTA TGC GCG CTG GGC GGG GGC GGC CCC GGC CTG CGA CCC CCG CCC 576 Ala Leu Cys Ala Leu Gly Gly Gly Gly Pro Gly Leu Arg Pro Pro Pro 15 20 25 GGC TGT CCC CAG CGA CGT CTG GGC GCG CGC GAG CGC CGG GAC GTG CAG 624 Gly Cys Pro Gin Arg Arg Leu Gly Ala Arg Glu Arg Arg Asp Val Gin 30 35 40 45 CGC GAG ATC CTG GCG GTG CTC GGG CTG CCT GGG CGG CCC CGG CCC CGC 672 Arg Glu He Leu Ala Val Leu Gly Leu Pro Gly Arg Pro Arg Pro Arg 50 55 60 GCG CCA CCC GCC GCC TCC CGG CTG CCC GCG TCC GCG CCG CTC TTC ATG 720 Ala Pro Pro Ala Ala Ser Arg Leu Pro Ala Ser Ala Pro Leu Phe Met 65 70 75 CTG GAC CTG TAC CAC GCC ATG GCC GGC GAC GAC GAC GAG GAC GGC GCG 768 Leu Asp Leu Tyr His Ala Met Ala Gly Asp Asp Asp Glu Asp Gly Ala 80 85 90 CCC GCG GAG CGG CGC CTG GGC CGC GCC GAC CTG GTC ATG AGC TTC GTT 816 Pro Ala Glu Arg Arg Leu Gly Arg Ala Asp Leu Val Met Ser Phe Val 95 100 105 AAC ATG GTG GAG CGA GAC CGT GCC CTG GGC CAC CAG GAG CCC CAT TGG 864 Asn Met Val Glu Arg Asp Arg Ala Leu Gly His Gin Glu Pro His Trp 110 115 120 125 AAG GAG TTC CGC TTT GAC CTG ACC CAG ATC CCG GCT GGG GAG GCG GTC 912 Lys Glu Phe Arg Phe Asp Leu Thr Gin He Pro Ala Gly Glu Ala Val 130 135 140 ACA GCT GCG GAG TTC CGG ATT TAC AAG GTG CCC AGC ATC CAC CTG CTC 960 Thr Ala Ala Glu Phe Arg He Tyr Lys Val Pro Ser He His Leu Leu 145 150 155 AAC AGG ACC CTC CAC GTC AGC ATG TTC CAG GTG GTC CAG GAG CAG TCC 1008 Asn Arg Thr Leu His Val Ser Met Phe Gin Val Val Gin Glu Gin Ser 160 165 170 AAC AGG GAG TCT GAC TTG TTC TTT TTG GAT CTT CAG ACG CTC CGA GCT 1056 Asn Arg Glu Ser Asp Leu Phe Phe Leu Asp Leu Gin Thr Leu Arg Ala 175 180 185 GGA GAC GAG GGC TGG CTG GTG CTG GAT GTC ACA GCA GCC AGT GAC TGC 1104 Gly Asp Glu Gly Trp Leu Val Leu Asp Val Thr Ala Ala Ser Asp Cys 190 195 200 205 TGG TTG CTG AAG CGT CAC AAG GAC CTG GGA CTC CGC CTC TAT GTG GAG 1152 Trp Leu Leu Lys Arg His Lys Asp Leu Gly Leu Arg Leu Tyr Val Glu 210 215 220 ACT GAG GAC GGG CAC AGC GTG GAT CCT GGC CTG GCC GGC CTG CTG GGT 1200 Thr Glu Asp Gly His Ser Val Asp Pro Gly Leu Ala Gly Leu Leu Gly 225 230 235 CAA CGG GCC CCA CGC TCC CAA CAG CCT TTC GTG GTC ACT TTC TTC AGG 1248 Gin Arg Ala Pro Arg Ser Gin Gin Pro Phe Val Val Thr Phe Phe Arg 240 245 250 GCC AGT CCG AGT CCC ATC CGC ACC CCT CGG GCA GTG AGG CCA CTG AGG 1296 Ala Ser Pro Ser Pro He Arg Thr Pro Arg Ala Val Arg Pro Leu Arg 255 260 265 AGG AGG CAG CCG AAG AAA AGC AAC GAG CTG CCG CAG GCC AAC CGA CTC 1344 Arg Arg Gin Pro Lys Lys Ser Asn Glu Leu Pro Gin Ala Asn Arg Leu 270 275 280 285 CCA GGG ATC TTT GAT GAC GTC CAC GGC TCC CAC GGC CGG CAG GTC TGC 1392 Pro Gly He Phe Asp Asp Val His Gly Ser His Gly Arg Gin Val Cys 290 295 300 CGT CGG CAC GAG CTC TAC GTC AGC TTC CAG GAC CTC GGC TGG CTG GAC 1440 Arg Arg His Glu Leu Tyr Val Ser Phe Gin Asp Leu Gly Trp Leu Asp 305 310 315 TGG GTC ATC GCT CCC CAA GGC TAC TCG GCC TAT TAC TGT GAG GGG GAG 1488 Trp Val He Ala Pro Gin Gly Tyr Ser Ala Tyr Tyr Cys Glu Gly Glu 320 325 330 TGC TCC TTC CCA CTG GAC TCC TGC ATG AAT GCC ACC AAC CAC GCC ATC 1536 Cys Ser Phe Pro Leu Asp Ser Cys Met Asn Ala Thr Asn His Ala He 335 340 345 CTG CAG TCC CTG GTG CAC CTG ATG AAG CCA AAC GCA GTC CCC AAG GCG 1584 Leu Gin Ser Leu Val His Leu Met Lys Pro Asn Ala Val Pro Lys Ala 350 355 360 365 TGC TGT GCA CCC ACC AAG CTG AGC GCC ACC TCT GTG CTC TAC TAT GAC 1632 Cys Cys Ala Pro Thr Lys Leu Ser Ala Thr Ser Val Leu Tyr Tyr Asp 370 375 380 AGC AGC AAC AAC GTC ATC CTG CGC AAA GCC CGC AAC ATG GTG GTC AAG 1680 Ser Ser Asn Asn Val He Leu Arg Lys Ala Arg Asn Met Val Val Lys 385 390 395 GCC TGC GGC TGC CAC T GAGTCAGCCC GCCCAGCCCT ACTGCAG 1723 Ala Cys Gly Cys His 400 (2) INFORMATION FOR SEQ ID NO:21: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 402 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:21: Met Thr Ala Leu Pro Gly Pro Leu Trp Leu Leu Gly Leu Ala Leu Cys 1 5 10 15 Ala Leu Gly Gly Gly Gly Pro Gly Leu Arg Pro Pro Pro Gly Cys Pro 20 25 30 Gin Arg Arg Leu Gly Ala Arg Glu Arg Arg Asp Val Gin Arg Glu He 35 40 45 Leu Ala Val Leu Gly Leu Pro Gly Arg Pro Arg Pro Arg Ala Pro Pro 50 55 60 Ala Ala Ser Arg Leu Pro Ala Ser Ala Pro Leu Phe Met Leu Asp Leu 65 70 75 80 Tyr His Ala Met Ala Gly Asp Asp Asp Glu Asp Gly Ala Pro Ala Glu 85 90 95 Arg Arg Leu Gly Arg Ala Asp Leu Val Met Ser Phe Val Asn Met Val 100 105 110 Glu Arg Asp Arg Ala Leu Gly His Gin Glu Pro His Trp Lys Glu Phe 115 120 125 Arg Phe Asp Leu Thr Gin He Pro Ala Gly Glu Ala Val Thr Ala Ala 130 135 140 Glu Phe Arg He Tyr Lys Val Pro Ser He His Leu Leu Asn Arg Thr 145 150 155 160 Leu His Val Ser Met Phe Gin Val Val Gin Glu Gin Ser Asn Arg Glu 165 170 175 Ser Asp Leu Phe Phe Leu Asp Leu Gin Thr Leu Arg Ala Gly Asp Glu 180 185 190 Gly Trp Leu Val Leu Asp Val Thr Ala Ala Ser Asp Cys Trp Leu Leu 195 200 205 Lys Arg His Lys Asp Leu Gly Leu Arg Leu Tyr Val Glu Thr Glu Asp 210 215 220 Gly His Ser Val Asp Pro Gly Leu Ala Gly Leu Leu Gly Gin Arg Ala 225 230 235 240 Pro Arg Ser Gin Gin Pro Phe Val Val Thr Phe Phe Arg Ala Ser Pro 245 250 255 Ser Pro He Arg Thr Pro Arg Ala Val Arg Pro Leu Arg Arg Arg Gin 260 265 270 Pro Lys Lys Ser Asn Glu Leu Pro Gin Ala Asn Arg Leu Pro Gly He 275 280 285 Phe Asp Asp Val His Gly Ser His Gly Arg Gin Val Cys Arg Arg His 290 295 300 Glu Leu Tyr Val Ser Phe Gin Asp Leu Gly Trp Leu Asp Trp Val He 305 310 315 320 Ala Pro Gin Gly Tyr Ser Ala Tyr Tyr Cys Glu Gly Glu Cys Ser Phe 325 330 335 Pro Leu Asp Ser Cys Met Asn Ala Thr Asn His Ala He Leu Gin Ser 340 345 350 Leu Val His Leu Met Lys Pro Asn Ala Val Pro Lys Ala Cys Cys Ala 355 360 365 Pro Thr Lys Leu Ser Ala Thr Ser Val Leu Tyr Tyr Asp Ser Ser Asn 370 375 380 Asn Val He Leu Arg Lys Ala Arg Asn Met Val Val Lys Ala Cys Gly 385 390 395 400 Cys His (2) INFORMATION FOR SEQ ID NO:22: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1926 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (vi) ORIGINAL SOURCE: (A) ORGANISM: MURIDAE (F) TISSUE TYPE: EMBRYO (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 93..1289 (D) OTHER INFORMATION: /function- "OSTEOGENIC PROTEIN" /product- "mOP2-PP" /note- "mOP2 cDNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:22: GCCAGGCACA GGTGCGCCGT CTGGTCCTCC CCGTCTGGCG TCAGCCGAGC CCGACCAGCT 60 ACCAGTGGAT GCGCGCCGGC TGAAAGTCCG AG ATG GCT ATG CGT CCC GGG CCA 113 Met Ala Met Arg Pro Gly Pro 1 5 CTC TGG CTA TTG GGC CTT GCT CTG TGC GCG CTG GGA GGC GGC CAC GGT 161 Leu Trp Leu Leu Gly Leu Ala Leu Cys Ala Leu Gly Gly Gly His Gly 10 15 20 CCG CGT CCC CCG CAC ACC TGT CCC CAG CGT CGC CTG GGA GCG CGC GAG 209 Pro Arg Pro Pro His Thr Cys Pro Gin Arg Arg Leu Gly Ala Arg Glu 25 30 35 CGC CGC GAC ATG CAG CGT GAA ATC CTG GCG GTG CTC GGG CTA CCG GGA 257 Arg Arg Asp Met Gin Arg Glu He Leu Ala Val Leu Gly Leu Pro Gly 40 45 50 55 CGG CCC CGA CCC CGT GCA CAA CCC GCC GCT GCC CGG CAG CCA GCG TCC 305 Arg Pro Arg Pro Arg Ala Gin Pro Ala Ala Ala Arg Gin Pro Ala Ser 60 65 70 GCG CCC CTC TTC ATG TTG GAC CTA TAC CAC GCC ATG ACC GAT GAC GAC 353 Ala Pro Leu Phe Met Leu Asp Leu Tyr His Ala Met Thr Asp Asp Asp 75 80 85 GAC GGC GGG CCA CCA CAG GCT CAC TTA GGC CGT GCC GAC CTG GTC ATG 401 Asp Gly Gly Pro Pro Gin Ala His Leu Gly Arg Ala Asp Leu Val Met 90 95 100 AGC TTC GTC AAC ATG GTG GAA CGC GAC CGT ACC CTG GGC TAC CAG GAG 449 Ser Phe Val Asn Met Val Glu Arg Asp Arg Thr Leu Gly Tyr Gin Glu 105 110 115 CCA CAC TGG AAG GAA TTC CAC TTT GAC CTA ACC CAG ATC CCT GCT GGG 497 Pro His Trp Lys Glu Phe His Phe Asp Leu Thr Gin He Pro Ala Gly 120 125 130 135 GAG GCT GTC ACA GCT GCT GAG TTC CGG ATC TAC AAA GAA CCC AGC ACC 545 Glu Ala Val Thr Ala Ala Glu Phe Arg He Tyr Lys Glu Pro Ser Thr 140 145 150 CAC CCG CTC AAC ACA ACC CTC CAC ATC AGC ATG TTC GAA GTG GTC CAA 593 His Pro Leu Asn Thr Thr Leu His He Ser Met Phe Glu Val Val Gin 155 160 165 GAG CAC TCC AAC AGG GAG TCT GAC TTG TTC TTT TTG GAT CTT CAG ACG 641 Glu His Ser Asn Arg Glu Ser Asp Leu Phe Phe Leu Asp Leu Gin Thr 170 175 180 CTC CGA TCT GGG GAC GAG GGC TGG CTG GTG CTG GAC ATC ACA GCA GCC 689 Leu Arg Ser Gly Asp Glu Gly Trp Leu Val Leu Asp He Thr Ala Ala 185 190 195 AGT GAC CGA TGG CTG CTG AAC CAT CAC AAG GAC CTG GGA CTC CGC CTC 737 Ser Asp Arg Trp Leu Leu Asn His His Lys Asp Leu Gly Leu Arg Leu 200 205 210 215 TAT GTG GAA ACC GCG GAT GGG CAC AGC ATG GAT CCT GGC CTG GCT GGT 785 Tyr Val Glu Thr Ala Asp Gly His Ser Met Asp Pro Gly Leu Ala Gly 220 225 230 CTG CTT GGA CGA CAA GCA CCA CGC TCC AGA CAG CCT TTC ATG GTA ACC 833 Leu Leu Gly Arg Gin Ala Pro Arg Ser Arg Gin Pro Phe Met Val Thr 235 240 245 TTC TTC AGG GCC AGC CAG AGT CCT GTG CGG GCC CCT CGG GCA GCG AGA 881 Phe Phe Arg Ala Ser Gin Ser Pro Val Arg Ala Pro Arg Ala Ala Arg 250 255 260 CCA CTG AAG AGG AGG CAG CCA AAG AAA ACG AAC GAG CTT CCG CAC CCC 929 Pro Leu Lys Arg Arg Gin Pro Lys Lys Thr Asn Glu Leu Pro His Pro 265 270 275 AAC AAA CTC CCA GGG ATC TTT GAT GAT GGC CAC GGT TCC CGC GGC AGA 977 Asn Lys Leu Pro Gly He Phe Asp Asp Gly His Gly Ser Arg Gly Arg 280 285 290 295 GAG GTT TGC CGC AGG CAT GAG CTC TAC GTC AGC TTC CGT GAC CTT GGC 1025 Glu Val Cys Arg Arg His Glu Leu Tyr Val Ser Phe Arg Asp Leu Gly 300 305 310 TGG CTG GAC TGG GTC ATC GCC CCC CAG GGC TAC TCT GCC TAT TAC TGT 1073 Trp Leu Asp Trp Val He Ala Pro Gin Gly Tyr Ser Ala Tyr Tyr Cys 315 320 325 GAG GGG GAG TGT GCT TTC CCA CTG GAC TCC TGT ATG AAC GCC ACC AAC 1121 Glu Gly Glu Cys Ala Phe Pro Leu Asp Ser Cys Met Asn Ala Thr Asn 330 335 340 CAT GCC ATC TTG CAG TCT CTG GTG CAC CTG ATG AAG CCA GAT GTT GTC 1169 His Ala He Leu Gin Ser Leu Val His Leu Met Lys Pro Asp Val Val 345 350 355 CCC AAG GCA TGC TGT GCA CCC ACC AAA CTG AGT GCC ACC TCT GTG CTG 1217 Pro Lys Ala Cys Cys Ala Pro Thr Lys Leu Ser Ala Thr Ser Val Leu 360 365 370 375 TAC TAT GAC AGC AGC AAC AAT GTC ATC CTG CGT AAA CAC CGT AAC ATG 1265 Tyr Tyr Asp Ser Ser Asn Asn Val He Leu Arg Lys His Arg Asn Met 380 385 390 GTG GTC AAG GCC TGT GGC TGC CAC TGAGGCCCCG CCCAGCATCC TGCTTCTACT 1319 Val Val Lys Ala Cys Gly Cys His 395 ACCTTACCAT CTGGCCGGGC CCCTCTCCAG AGGCAGAAAC CCTTCTATGT TATCATAGCT 1379 CAGACAGGGG CAATGGGAGG CCCTTCACTT CCCCTGGCCA CTTCCTGCTA AAATTCTGGT 1439 CTTTCCCAGT TCCTCTGTCC TTCATGGGGT TTCGGGGCTA TCACCCCGCC CTCTCCATCC 1499 TCCTACCCCA AGCATAGACT GAATGCACAC AGCATCCCAG AGCTATGCTA ACTGAGAGGT 1559 CTGGGGTCAG CACTGAAGGC CCACATGAGG AAGACTGATC CTTGGCCATC CTCAGCCCAC 1619 AATGGCAAAT TCTGGATGGT CTAAGAAGGC CCTGGAATTC TAAACTAGAT GATCTGGGCT 1679 CTCTGCACCA TTCATTGTGG CAGTTGGGAC ATTTTTAGGT ATAACAGACA CATACACTTA 1739 GATCAATGCA TCGCTGTACT CCTTGAAATC AGAGCTAGCT TGTTAGAAAA AGAATCAGAG 1799 CCAGGTATAG CGGTGCATGT CATTAATCCC AGCGCTAAAG AGACAGAGAC AGGAGAATCT 1859 CTGTGAGTTC AAGGCCACAT AGAAAGAGCC TGTCTCGGGA GCAGGAAAAA AAAAAAAAAC 1919 GGAATTC 1926 (2) INFORMATION FOR SEQ ID NO:23: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 399 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:23: Met Ala Met Arg Pro Gly Pro Leu Trp Leu Leu Gly Leu Ala Leu Cys 1 5 10 15 Ala Leu Gly Gly Gly His Gly Pro Arg Pro Pro His Thr Cys Pro Gin 20 25 30 Arg Arg Leu Gly Ala Arg Glu Arg Arg Asp Met Gin Arg Glu He Leu 35 40 45 Ala Val Leu Gly Leu Pro Gly Arg Pro Arg Pro Arg Ala Gin Pro Ala 50 55 60 Ala Ala Arg Gin Pro Ala Ser Ala Pro Leu Phe Met Leu Asp Leu Tyr 65 70 75 80 His Ala Met Thr Asp Asp Asp Asp Gly Gly Pro Pro Gin Ala His Leu 85 90 95 Gly Arg Ala Asp Leu Val Met Ser Phe Val Asn Met Val Glu Arg Asp 100 105 110 Arg Thr Leu Gly Tyr Gin Glu Pro His Trp Lys Glu Phe His Phe Asp 115 120 125 Leu Thr Gin He Pro Ala Gly Glu Ala Val Thr Ala Ala Glu Phe Arg 130 135 140 He Tyr Lys Glu Pro Ser Thr His Pro Leu Asn Thr Thr Leu His He 145 150 155 160 Ser Met Phe Glu Val Val Gin Glu His Ser Asn Arg Glu Ser Asp Leu 165 170 175 Phe Phe Leu Asp Leu Gin Thr Leu Arg Ser Gly Asp Glu Gly Trp Leu 180 185 190 Val Leu Asp He Thr Ala Ala Ser Asp Arg Trp Leu Leu Asn His His 195 200 205 Lys Asp Leu Gly Leu Arg Leu Tyr Val Glu Thr Ala Asp Gly His Ser 210 215 220 Met Asp Pro Gly Leu Ala Gly Leu Leu Gly Arg Gin Ala Pro Arg Ser 225 230 235 240 Arg Gin Pro Phe Met Val Thr Phe Phe Arg Ala Ser Gin Ser Pro Val 245 250 255 Arg Ala Pro Arg Ala Ala Arg Pro Leu Lys Arg Arg Gin Pro Lys Lys 260 265 270 Thr Asn Glu Leu Pro His Pro Asn Lys Leu Pro Gly He Phe Asp Asp 275 280 285 Gly His Gly Ser Arg Gly Arg Glu Val Cys Arg Arg His Glu Leu Tyr 290 295 300 Val Ser Phe Arg Asp Leu Gly Trp Leu Asp Trp Val He Ala Pro Gin 305 310 315 320 Gly Tyr Ser Ala Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asp 325 330 335 Ser Cys Met Asn Ala Thr Asn His Ala He Leu Gin Ser Leu Val His 340 345 350 Leu Met Lys Pro Asp Val Val Pro Lys Ala Cys Cys Ala Pro Thr Lys 355 360 365 Leu Ser Ala Thr Ser Val Leu Tyr Tyr Asp Ser Ser Asn Asn Val He 370 375 380 Leu Arg Lys His Arg Asn Met Val Val Lys Ala Cys Gly Cys His 385 390 395 (2) INFORMATION FOR SEQ ID NO:24: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1368 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 1..1368 (xi) SEQUENCE DESCRIPTION: SEQ ID N0:24: ATG TCG GGA CTG CGA AAC ACC TCG GAG GCC GTT GCA GTG CTC GCC TCC 48 Met Ser Gly Leu Arg Asn Thr Ser Glu Ala Val Ala Val Leu Ala Ser 1 5 10 15 CTG GGA CTC GGA ATG GTT CTG CTC ATG TTC GTG GCG ACC ACG CCG CCG 96 Leu Gly Leu Gly Met Val Leu Leu Met Phe Val Ala Thr Thr Pro Pro 20 25 30 GCC GTT GAG GCC ACC CAG TCG GGG ATT TAC ATA GAC AAC GGC AAG GAC 144 Ala Val Glu Ala Thr Gin Ser Gly He Tyr He Asp Asn Gly Lys Asp 35 40 45 CAG ACG ATC ATG CAC AGA GTG CTG AGC GAG GAC GAC AAG CTG GAC GTC 192 Gin Thr He Met His Arg Val Leu Ser Glu Asp Asp Lys Leu Asp Val 50 55 60 TCG TAC GAG ATC CTC GAG TTC CTG GGC ATC GCC GAA CGG CCG ACG CAC 240 Ser Tyr Glu He Leu Glu Phe Leu Gly He Ala Glu Arg Pro Thr His 65 70 75 80 CTG AGC AGC CAC CAG TTG TCG CTG AGG AAG TCG GCT CCC AAG TTC CTG 288 Leu Ser Ser His Gin Leu Ser Leu Arg Lys Ser Ala Pro Lys Phe Leu 85 90 95 CTG GAC GTC TAC CAC CGC ATC ACG GCG GAG GAG GGT CTC AGC GAT CAG 336 Leu Asp Val Tyr His Arg He Thr Ala Glu Glu Gly Leu Ser Asp Gin 100 105 110 GAT GAG GAC GAC GAC TAC GAA CGC GGC CAT CGG TCC AGG AGG AGC GCC 384 Asp Glu Asp Asp Asp Tyr Glu Arg Gly His Arg Ser Arg Arg Ser Ala 115 120 125 GAC CTC GAG GAG GAT GAG GGC GAG CAG CAG AAG AAC TTC ATC ACC GAC 432 Asp Leu Glu Glu Asp Glu Gly Glu Gin Gin Lys Asn Phe He Thr Asp 130 135 140 CTG GAC AAG CGG GCC ATC GAC GAG AGC GAC ATC ATC ATG ACC TTC CTG 480 Leu Asp Lys Arg Ala He Asp Glu Ser Asp He He Met Thr Phe Leu 145 150 155 160 AAC AAG CGC CAC CAC AAT GTG GAC GAA CTG CGT CAC GAG CAC GGC CGT 528 Asn Lys Arg His His Asn Val Asp Glu Leu Arg His Glu His Gly Arg 165 170 175 CGC CTG TGG TTC GAC GTC TCC AAC GTG CCC AAC GAC AAC TAC CTG GTG 576 Arg Leu Trp Phe Asp Val Ser Asn Val Pro Asn Asp Asn Tyr Leu Val 180 ' 185 190 ATG GCC GAG CTG CGC ATC TAT CAG AAC GCC AAC GAG GGC AAG TGG CTG 624 Met Ala Glu Leu Arg He Tyr Gin Asn Ala Asn Glu Gly Lys Trp Leu 195 200 205 ACC GCC AAC AGG GAG TTC ACC ATC ACG GTA TAC GCC ATT GGC ACC GGC 672 Thr Ala Asn Arg Glu Phe Thr He Thr Val Tyr Ala He Gly Thr Gly 210 215 220 ACG CTG GGC CAG CAC ACC ATG GAG CCG CTG TCC TCG GTG AAC ACC ACC 720 Thr Leu Gly Gin His Thr Met Glu Pro Leu Ser Ser Val Asn Thr Thr 225 230 235 240 GGG GAC TAC GTG GGC TGG TTG GAG CTC AAC GTG ACC GAG GGC CTG CAC 768 Gly Asp Tyr Val Gly Trp Leu Glu Leu Asn Val Thr Glu Gly Leu His 245 250 255 GAG TGG CTG GTC AAG TCG AAG GAC AAT CAT GGC ATC TAC ATT GGA GCA 816 Glu Trp Leu Val Lys Ser Lys Asp Asn His Gly He Tyr He Gly Ala 260 265 270 CAC GCT GTC AAC CGA CCC GAC CGC GAG GTG AAG CTG GAC GAC ATT GGA 864 His Ala Val Asn Arg Pro Asp Arg Glu Val Lys Leu Asp Asp He Gly 275 280 285 CTG ATC CAC CGC AAG GTG GAC GAC GAG TTC CAG CCC TTC ATG ATC GGC 912 Leu He His Arg Lys Val Asp Asp Glu Phe Gin Pro Phe Met He Gly 290 295 300 TTC TTC CGC GGA CCG GAG CTG ATC AAG GCG ACG GCC CAC AGC AGC CAC 960 Phe Phe Arg Gly Pro Glu Leu He Lys Ala Thr Ala His Ser Ser His 305 310 315 320 CAC AGG AGC AAG CGA AGC GCC AGC CAT CCA CGC AAG CGC AAG AAG TCG 1008 His Arg Ser Lys Arg Ser Ala Ser His Pro Arg Lys Arg Lys Lys Ser 325 330 335 GTG TCG CCC AAC AAC GTG CCG CTG CTG GAA CCG ATG GAG AGC ACG CGC 1056 Val Ser Pro Asn Asn Val Pro Leu Leu Glu Pro Met Glu Ser Thr Arg 340 345 350 AGC TGC CAG ATG CAG ACC CTG TAC ATA GAC TTC AAG GAT CTG GGC TGG 1104 Ser Cys Gin Met Gin Thr Leu Tyr He Asp Phe Lys Asp Leu Gly Trp 355 360 365 CAT GAC TGG ATC ATC GCA CCA GAG GGC TAT GGC GCC TTC TAC TGC AGC 1152 His Asp Trp He He Ala Pro Glu Gly Tyr Gly Ala Phe Tyr Cys Ser 370 375 380 GGC GAG TGC AAT TTC CCG CTC AAT GCG CAC ATG AAC GCC ACG AAC CAT 1200 Gly Glu Cys Asn Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His 385 390 395 400 GCG ATC GTC CAG ACC CTG GTC CAC CTG CTG GAG CCC AAG AAG GTG CCC 1248 Ala He Val Gin Thr Leu Val His Leu Leu Glu Pro Lys Lys Val Pro 405 410 415 AAG CCC TGC TGC GCT CCG ACC AGG CTG GGA GCA CTA CCC GTT CTG TAC 1296 Lys Pro Cys Cys Ala Pro Thr Arg Leu Gly Ala Leu Pro Val Leu Tyr 420 425 430 CAC CTG AAC GAC GAG AAT GTG AAC CTG AAA AAG TAT AGA AAC ATG ATT 1344 His Leu Asn Asp Glu Asn Val Asn Leu Lys Lys Tyr Arg Asn Met He 435 440 445 GTG AAA TCC TGC GGG TGC CAT TGA 1368 Val Lys Ser Cys Gly Cys His 450 455 (2) INFORMATION FOR SEQ ID NO:25: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 455 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:25: Met Ser Gly Leu Arg Asn Thr Ser Glu Ala Val Ala Val Leu Ala Ser 1 5 10 15 Leu Gly Leu Gly Met Val Leu Leu Met Phe Val Ala Thr Thr Pro Pro 20 25 30 Ala Val Glu Ala Thr Gin Ser Gly He Tyr He Asp Asn Gly Lys Asp 35 40 45 Gin Thr He Met His Arg Val Leu Ser Glu Asp Asp Lys Leu Asp Val 50 55 60 Ser Tyr Glu He Leu Glu Phe Leu Gly He Ala Glu Arg Pro Thr His 65 70 75 80 Leu Ser Ser His Gin Leu Ser Leu Arg Lys Ser Ala Pro Lys Phe Leu 85 90 95 Leu Asp Val Tyr His Arg He Thr Ala Glu Glu Gly Leu Ser Asp Gin 100 105 110 Asp Glu Asp Asp Asp Tyr Glu Arg Gly His Arg Ser Arg Arg Ser Ala 115 120 125 Asp Leu Glu Glu Asp Glu Gly Glu Gin Gin Lys Asn Phe He Thr Asp 130 135 140 Leu Asp Lys Arg Ala He Asp Glu Ser Asp He He Met Thr Phe Leu 145 150 155 160 Asn Lys Arg His His Asn Val Asp Glu Leu Arg His Glu His Gly Arg 165 170 175 Arg Leu Trp Phe Asp Val Ser Asn Val Pro Asn Asp Asn Tyr Leu Val 180 185 190 Met Ala Glu Leu Arg He Tyr Gin Asn Ala Asn Glu Gly Lys Trp Leu 195 200 205 Thr Ala Asn Arg Glu Phe Thr He Thr Val Tyr Ala He Gly Thr Gly 210 215 220 Thr Leu Gly Gin His Thr Met Glu Pro Leu Ser Ser Val Asn Thr Thr 225 230 235 240 Gly Asp Tyr Val Gly Trp Leu Glu Leu Asn Val Thr Glu Gly Leu His 245 250 255 Glu Trp Leu Val Lys Ser Lys Asp Asn His Gly He Tyr He Gly Ala 260 265 270 His Ala Val Asn Arg Pro Asp Arg Glu Val Lys Leu Asp Asp He Gly 275 280 285 Leu He His Arg Lys Val Asp Asp Glu Phe Gin Pro Phe Met He Gly 290 295 300 Phe Phe Arg Gly Pro Glu Leu He Lys Ala Thr Ala His Ser Ser His 305 310 315 320 His Arg Ser Lys Arg Ser Ala Ser His ?ro Arg Lys Arg Lys Lys Ser 325 330 335 Val Ser Pro Asn Asn Val Pro Leu Leu Glu Pro Met Glu Ser Thr Arg 340 345 350 Ser Cys Gin Met Gin Thr Leu Tyr He Asp Phe Lys Asp Leu Gly Trp 355 360 365 His Asp Trp He He Ala Pro Glu Gly Tyr Gly Ala Phe Tyr Cys Ser 370 375 380 Gly Glu Cys Asn Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His 385 390 395 400 Ala He Val Gin Thr Leu Val His Leu Leu Glu Pro Lys Lys Val Pro 405 410 415 Lys Pro Cys Cys Ala Pro Thr Arg Leu Gly Ala Leu Pro Val Leu Tyr 420 425 430 His Leu Asn Asp Glu Asn Val Asn Leu Lys Lys Tyr Arg Asn Met He 435 440 445 Val Lys Ser Cys Gly Cys His 450 455 (2) INFORMATION FOR SEQ ID N0:26: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 104 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..104 (D) OTHER INFORMATION: /note- "BMP3" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:26: Cys Ala Arg Arg Tyr Leu Lys Val Asp Phe Ala Asp He Gly Trp Ser 1 5 10 15 Glu Trp He He Ser Pro Lys Ser Phe Asp Ala Tyr Tyr Cys Ser Gly 20 25 30 Ala Cys Gin Phe Pro Met Pro Lys Ser Leu Lys Pro Ser Asn His Ala 35 40 45 Thr He Gin Ser He Val Ala Arg Ala Val Gly Val Val Pro Gly He 50 55 60 Pro Glu Pro Cys Cys Val Pro Glu Lys Met Ser Ser Leu Ser He Leu 65 70 75 80 Phe Phe Asp Glu Asn Lys Asn Val Val Leu Lys Val Tyr Pro Asn Met 85 90 95 Thr Val Glu Ser Cys Ala Cys Arg 100 (2) INFORMATION FOR SEQ ID NO:27: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /note- "BMP5" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:27: Cys Lys Lys His Glu Leu Tyr Val Ser Phe Arg Asp Leu Gly Trp Gin 1 5 10 15 Asp Trp He He Ala Pro Glu Gly Tyr Ala Ala Phe Tyr Cys Asp Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His Ala 35 40 45 He Val Gin Thr Leu Val His Leu Met Phe Pro Asp His Val Pro Lys 50 55 60 Pro Cys Cys Ala Pro Thr Lys Leu Asn Ala He Ser Val Leu Tyr Phe 65 70 75 80 Asp Asp Ser Ser Asn Val He Leu Lys Lys Tyr Arg Asn Met Val Val 85 90 95 Arg Ser Cys Gly Cys His 100 (2) INFORMATION FOR SEQ ID NO:28: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /note- "BMP6" (xi) SEQUENCE DESCRIPTION: SEQ ID N0:28: Cys Arg Lys His Glu Leu Tyr Val Ser Phe Gin Asp Leu Gly Trp Gin 1 5 10 15 Asp Trp He He Ala Pro Lys Gly Tyr Ala Ala Asn Tyr Cys Asp Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His Ala 35 40 45 He Val Gin Thr Leu Val His Leu Met Asn Pro Glu Tyr Val Pro Lys 50 55 60 Pro Cys Cys Ala Pro Thr Lys Leu Asn Ala He Ser Val Leu Tyr Phe 65 70 75 80 Asp Asp Asn Ser Asn Val He Leu Lys Lys Tyr Arg Trp Met Val Val 85 90 95 Arg Ala Cys Gly Cys His 100 (2) INFORMATION FOR SEQ ID NO:29: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /label- OPX /note- "WHEREIN EACH XAA IS INDEPENDENTLY SELECTED FROM A GROUP OF ONE OR MORE SPECIFIED AMINO ACIDS AS DEFINED IN THE SPECIFICATION (SECTION II.B.2.)" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:29: Cys Xaa Xaa His Glu Leu Tyr Val Xaa Phe Xaa Asp Leu Gly Trp Xaa 1 5 10 15 Asp Trp Xaa He Ala Pro Xaa Gly Tyr Xaa Ala Tyr Tyr Cys Glu Gly 20 25 30 Glu Cys Xaa Phe Pro Leu Xaa Ser Xaa Met Asn Ala Thr Asn His Ala 35 40 45 He Xaa Gin Xaa Leu Val His Xaa Xaa Xaa Pro Xaa Xaa Val Pro Lys 50 55 60 Xaa Cys Cys Ala Pro Thr Xaa Leu Xaa Ala Xaa Ser Val Leu Tyr Xaa 65 70 75 80 Asp Xaa Ser Xaa Asn Val Xaa Leu Xaa Lys Xaa Arg Asn Met Val Val 85 90 95 Xaa Ala Cys Gly Cys His 100 (2) INFORMATION FOR SEQ ID NO:30: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 97 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..97 (D) OTHER INFORMATION: /label- GENERIC-SEQ5 /note- "WHEREIN EACH XAA IS INDEPENDENTLY SELECTED FROM A GROUP OF ONE OR MORE SPECIFIED AMINO ACIDS AS DEFINED IN THE SPECIFICATION." (xi) SEQUENCE DESCRIPTION: SEQ ID NO:30: Leu Xaa Xaa Xaa Phe Xaa Xaa Xaa Gly Trp Xaa Xaa Trp Xaa Xaa Xaa 1 5 10 15 Pro Xaa Xaa Xaa Xaa Ala Xaa Tyr Cys Xaa Gly Xaa Cys Xaa Xaa Pro 20 25 30 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asn His Ala Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Cys Xaa Pro 50 55 60 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Leu Xaa Xaa Xaa Xaa Xaa Xaa Xaa 65 70 75 80 Val Xaa Leu Xaa Xaa Xaa Xaa Xaa Met Xaa Val Xaa Xaa Cys Xaa Cys 85 90 95 Xaa (2) INFORMATION FOR SEQ ID NO:31: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 102 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) HOLECULE TYPE: protein (ix) FEATURE: (A) NAME/KEY: Protein (B) LOCATION: 1..102 (D) OTHER INFORMATION: /label- GENERIC-SEQ6 /note- "WHEREIN EACH XAA IS INDEPENDENTLY SELECTED FROM A GROUP OF ONE OR MORE SPECIFIED AMINO ACIDS AS DEFINED IN THE SPECIFICATION. " (xi) SEQUENCE DESCRIPTION: SEQ ID N0:31: Cys Xaa Xaa Xaa Xaa Leu Xaa Xaa Xaa Phe Xaa Xaa Xaa Gly Trp Xaa 1 5 10 15 Xaa Trp Xaa Xaa Xaa Pro Xaa Xaa Xaa Xaa Ala Xaa Tyr Cys Xaa Gly 20 25 30 Xaa Cys Xaa Xaa Pro Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asn His Ala 35 40 45 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55 60 Xaa Cys Cys Xaa Pro Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Leu Xaa Xaa 65 70 75 80 Xaa Xaa Xaa Xaa Xaa Val Xaa Leu Xaa Xaa Xaa Xaa Xaa Met Xaa Val 85 90 95 Xaa Xaa Cys Xaa Cys Xaa 100 (2) INFORMATION FOR SEQ ID NO:32: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1247 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (vi) ORIGINAL SOURCE: (A) ORGANISM: HOMO SAPIENS (F) TISSUE TYPE: BRAIN (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 84..1199 (D) OTHER INFORMATION: /product- "GDF-1" /note- "GDF-1 CDNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:32: GGGGACACCG GCCCCGCCCT CAGCCCACTG GTCCCGGGCC GCCGCGGACC CTGCGCACTC 60 TCTGGTCATC GCCTGGGAGG AAG ATG CCA CCG CCG CAG CAA GGT CCC TGC 110 Met Pro Pro Pro Gin Gin Gly Pro Cys 1 5 GGC CAC CAC CTC CTC CTC CTC CTG GCC CTG CTG CTG CCC TCG CTG CCC 158 Gly His His Leu Leu Leu Leu Leu Ala Leu Leu Leu Pro Ser Leu Pro 10 15 20 25 CTG ACC CGC GCC CCC GTG CCC CCA GGC CCA GCC GCC GCC CTG CTC CAG 206 Leu Thr Arg Ala Pro Val Pro Pro Gly Pro Ala Ala Ala Leu Leu Gin 30 35 40 GCT CTA GGA CTG CGC GAT GAG CCC CAG GGT GCC CCC AGG CTC CGG CCG 254 Ala Leu Gly Leu Arg Asp Glu Pro Gin Gly Ala Pro Arg Leu Arg Pro 45 50 55 GTT CCC CCG GTC ATG TGG CGC CTG TTT CGA CGC CGG GAC CCC CAG GAG 302 Val Pro Pro Val Met Trp Arg Leu Phe Arg Arg Arg Asp Pro Gin Glu 60 65 70 ACC AGG TCT GGC TCG CGG CGG ACG TCC CCA GGG GTC ACC CTG CAA CCG 350 Thr Arg Ser Gly Ser Arg Arg Thr Ser Pro Gly Val Thr Leu Gin Pro 75 80 85 TGC CAC GTG GAG GAG CTG GGG GTC GCC GGA AAC ATC GTG CGC CAC ATC 398 Cys His Val Glu Glu Leu Gly Val Ala Gly Asn He Val Arg His He 90 95 100 105 CCG GAC CGC GGT GCG CCC ACC CGG GCC TCG GAG CCT GTC TCG GCC GCG 446 Pro Asp Arg Gly Ala Pro Thr Arg Ala Ser Glu Pro Val Ser Ala Ala 110 115 120 GGG CAT TGC CCT GAG TGG ACA GTC GTC TTC GAC CTG TCG GCT GTG GAA 494 Gly His Cys Pro Glu Trp Thr Val Val Phe Asp Leu Ser Ala Val Glu 125 130 135 CCC GCT GAG CGC CCG AGC CGG GCC CGC CTG GAG CTG CGT TTC GCG GCG 542 Pro Ala Glu Arg Pro Ser Arg Ala Arg Leu Glu Leu Arg Phe Ala Ala 140 145 150 GCG GCG GCG GCA GCC CCG GAG GGC GGC TGG GAG CTG AGC GTG GCG CAA 590 Ala Ala Ala Ala Ala Pro Glu Gly Gly Trp Glu Leu Ser Val Ala Gin 155 160 165 GCG GGC CAG GGC GCG GGC GCG GAC CCC GGG CCG GTG CTG CTC CGC CAG 638 Ala Gly Gin Gly Ala Gly Ala Asp Pro Gly Pro Val Leu Leu Arg Gin 170 175 180 185 TTG GTG CCC GCC CTG GGG CCG CCA GTG CGC GCG GAG CTG CTG GGC GCC 686 Leu Val Pro Ala Leu Gly Pro Pro Val Arg Ala Glu Leu Leu Gly Ala 190 195 200 GCT TGG GCT CGC AAC GCC TCA TGG CCG CGC AGC CTC CGC CTG GCG CTG 734 Ala Trp Ala Arg Asn Ala Ser Trp Pro Arg Ser Leu Arg Leu Ala Leu 205 210 215 GCG CTA CGC CCC CGG GCC CCT GCC GCC TGC GCG CGC CTG GCC GAG GCC 782 Ala Leu Arg Pro Arg Ala Pro Ala Ala Cys Ala Arg Leu Ala Glu Ala 220 225 230 TCG CTG CTG CTG GTG ACC CTC GAC CCG CGC CTG TGC CAC CCC CTG GCC 830 Ser Leu Leu Leu Val Thr Leu Asp Pro Arg Leu Cys His Pro Leu Ala 235 240 245 CGG CCG CGG CGC GAC GCC GAA CCC GTG TTG GGC GGC GGC CCC GGG GGC 878 Arg Pro Arg Arg Asp Ala Glu Pro Val Leu Gly Gly Gly Pro Gly Gly 250 255 260 265 GCT TGT CGC GCG CGG CGG CTG TAC GTG AGC TTC CGC GAG GTG GGC TGG 926 Ala Cys Arg Ala Arg Arg Leu Tyr Val Ser Phe Arg Glu Val Gly Trp 270 275 280 CAC CGC TGG GTC ATC GCG CCG CGC GGC TTC CTG GCC AAC TAC TGC CAG 974 His Arg Trp Val He Ala Pro Arg Gly Phe Leu Ala Asn Tyr Cys Gin 285 290 295 GGT CAG TGC GCG CTG CCC GTC GCG CTG TCG GGG TCC GGG GGG CCG CCG 1022 Gly Gin Cys Ala Leu Pro Val Ala Leu Ser Gly Ser Gly Gly Pro Pro 300 305 310 GCG CTC AAC CAC GCT GTG CTG CGC GCG CTC ATG CAC GCG GCC GCC CCG 1070 Ala Leu Asn His Ala Val Leu Arg Ala Leu Met His Ala Ala Ala Pro 315 320 325 GGA GCC GCC GAC CTG CCC TGC TGC GTG CCC GCG CGC CTG TCG CCC ATC 1118 Gly Ala Ala Asp Leu Pro Cys Cys Val Pro Ala Arg Leu Ser Pro He 330 335 340 345 TCC GTG CTC TTC TTT GAC AAC AGC GAC AAC GTG GTG CTG CGG CAG TAT 1166 Ser Val Leu Phe Phe Asp Asn Ser Asp Asn Val Val Leu Arg Gin Tyr 350 355 360 GAG GAC ATG GTG GTG GAC GAG TGC GGC TGC CGC TAACCCGGGG CGGGCAGGGA 1219 Glu Asp Met Val Val Asp Glu Cys Gly Cys Arg 365 370 CCCGGGCCCA ACAATAAATG CCGCGTGG 1247 (2) INFORMATION FOR SEQ ID NO:33: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 372 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:33: Met Pro Pro Pro Gin Gin Gly Pro Cys Gly His His Leu Leu Leu Leu 1 5 10 15 Leu Ala Leu Leu Leu Pro Ser Leu Pro Leu Thr Arg Ala Pro Val Pro 20 25 30 Pro Gly Pro Ala Ala Ala Leu Leu Gin Ala Leu Gly Leu Arg Asp Glu 35 40 45 Pro Gin Gly Ala Pro Arg Leu Arg Pro Val Pro Pro Val Met Trp Arg 50 55 60 Leu Phe Arg Arg Arg Asp Pro Gin Glu Thr Arg Ser Gly Ser Arg Arg 65 70 75 80 Thr Ser Pro Gly Val Thr Leu Gin Pro Cys His Val Glu Glu Leu Gly 85 90 95 Val Ala Gly Asn He Val Arg His He Pro Asp Arg Gly Ala Pro Thr 100 105 110 Arg Ala Ser Glu Pro Val Ser Ala Ala Gly His Cys Pro Glu Trp Thr 115 120 125 Val Val Phe Asp Leu Ser Ala Val Glu Pro Ala Glu Arg Pro Ser Arg 130 135 140 Ala Arg Leu Glu Leu Arg Phe Ala Ala Ala Ala Ala Ala Ala Pro Glu 145 150 155 160 Gly Gly Trp Glu Leu Ser Val Ala Gin Ala Gly Gin Gly Ala Gly Ala 165 170 175 Asp Pro Gly Pro Val Leu Leu Arg Gin Leu Val Pro Ala Leu Gly Pro 180 185 190 Pro Val Arg Ala Glu Leu Leu Gly Ala Ala Trp Ala Arg Asn Ala Ser 195 200 205 Trp Pro Arg Ser Leu Arg Leu Ala Leu Ala Leu Arg Pro Arg Ala Pro 210 215 220 Ala Ala Cys Ala Arg Leu Ala Glu Ala Ser Leu Leu Leu Val Thr Leu 225 230 235 240 Asp Pro Arg Leu Cys His Pro Leu Ala Arg Pro Arg Arg Asp Ala Glu 245 250 255 Pro Val Leu Gly Gly Gly Pro Gly Gly Ala Cys Arg Ala Arg Arg Leu 260 265 270 Tyr Val Ser Phe Arg Glu Val Gly Trp His Arg Trp Val He Ala Pro 275 280 285 Arg Gly Phe Leu Ala Asn Tyr Cys Gin Gly Gin Cys Ala Leu Pro Val 290 295 300 Ala Leu Ser Gly Ser Gly Gly Pro Pro Ala Leu Asn His Ala Val Leu 305 310 315 320 Arg Ala Leu Met His Ala Ala Ala Pro Gly Ala Ala Asp Leu Pro Cys 325 330 335 Cys Val Pro Ala Arg Leu Ser Pro He Ser Val Leu Phe Phe Asp Asn 340 345 350 Ser Asp Asn Val Val Leu Arg Gin Tyr Glu Asp Met Val Val Asp Glu 355 360 365 Cys Gly Cys Arg 370

Claims: What is claimed is: 1. The use of a morphogen in the manufacture of a pharmaceutical for enhancing survival of neural cells at risk of dying. 2. A method for enhancing survival of neural cells at risk of dying, the method comprising providing a morphogen to said cells at a concentration and for a time sufficient to enhance survival of said cells. 3. The invention of claim 1 or 2 wherein said cells are at risk of dying due to chemical or mechanical trauma to nerve tissue comprising said cells. 4. The invention of claim 3 wherein said trauma comprises a transected nerve. 5. The invention of claim 3 wherein said morphogen is provided to said cells prior to said trauma. 6. The invention of claim 3 wherein said trauma results in demyelination of said cells. 7. The invention of claim 3 wherein said trauma results from exposure of said cells to a cellular toxin. 8. The invention of claim 7 wherein said toxin comprises ethanol. 9. The invention of claim 1 or 2 wherein said cells are at risk of dying due to a neuropathy. 10. The invention of claim 9 wherein the etiology of said neuropathy is metabolic, infectious, toxic, autoimmune, nutritional, or ischemic. 11. The invention of claim 10 wherein said neuropathy comprises Parkinson's disease, Huntington's chorea, amyotrophic lateral sclerosis, multiple sclerosis or Alzheimer's disease. 12. The invention of_claim 1 or 2 wherein said cells are at risk of ying due a neoplastic lesion associated with nerve tissue comprising said cells. 13. The invention of claim 12 wherein said lesion results from a neoplasm comprising cells of neuronal origin. 14. The invention of claim 13 wherein said neoplasm comprises a neuroblastoma or a retinoblastoma. 15. The invention of claim 12 wherein said lesion results from a neoplasm comprising glial cells. 16. The invention of claim 1 or 2 wherein said neural cells at risk of dying comprise part of the central nervous system. 17. The invention of claim 16 wherein said cells comprise striatal basal ganglia neurons. 18. The invention of claim 16 wherein said cells comprise neurons of the substantia nigra. 19. The invention of claim 1 or 2 wherein said cells at risk of dying comprise part of the peripheral nervous system. 20. The invention of claim 1 or 2 wherein said morphogen stimulates cell adhesion molecule production in said cells. 21. The invention of claim 20 wherein said cell adhesion molecule is a nerve cell adhesion molecule. 22. The invention of claim 21 wherein nerve cell adhesion molecule is selected from the group consisting of N-CAM-120, N-CAM-140 and N-CAM-180. 23. The invention of claim 1 or 2 wherein said morphogen comprises an amino acid sequence sharing at least 70% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-l(fx) and 60A(fx). 24. The invention of claim 23 wherein said morphogen comprises an amino acid sequence sharing at least 80% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-1(fx), and 60A (fx). 25. The invention of claim 24 wherein said morphogen comprises an amino acid sequence having greater than 60% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 26. The invention of claim 25 wherein said morphogen comprises an amino acid sequence having greater than 65% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 27. The invention of claim 22 wherein said morphogen comprises an amino acid sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl), including allelic and species variants thereof. 28. A method for enhancing the survival of neural cells at risk of dying in a mammal, the method comprising the step of administering to said mammal an effective amount of an agent capable of stimulating production of an endogenous morphogen. 29. The method of claim 28 wherein said agent stimulates production of an endogenous morphogen in the tissue comprising said neural cells. 30. A method for maintaining a neural pathway in a mammal, comprising: providing a morphogen to the neurons defining said pathway at a concentration and for a time sufficient to maintain said pathway. 31. The method of claim 30 wherein said morphogen is provided prior to injury to said pathway. 32. The method of claim 30 wherein said morphogen is sufficient to stimulate repair of a damaged neural pathway. 33. The method of claim 32 wherein said damaged neural pathway, results from mechanical or chemical trauma to said pathway. 34. The method of claim 33 wherein said trauma comprises a severed nerve. 35. The method of claim 33 wherein said trauma comprises demyelination of the neurons defining said pathway. 36. The method of claim 33 wherein said trauma results from exposure of the cells defining said pathway to a cellular toxin. 37. The method of claim 36 wherein said toxin comprises ethanol. 38. The method of claim 30 wherein said damaged neural pathway results from a neuropathy of the cells defining said pathway. 39. The method of claim 38 wherein the etiology of said neuropathy is metabolic, infectious, toxic, autoimmune, nutritional, or ischemic. 40. The method of claim 39 wherein said neuropathy comprises Parkinson's disease, Huntington's chorea, amyotrophic lateral sclerosis, multiple sclerosis, or Alzheimer's disease. 41. The method of claim 38 wherein said neuropathy comprises axonal degeneration. 42. The method of claim 38 wherein said neuropathy comprises a demyelinating neuropathy. 43. The method of claim 30 wherein said damaged neural pathway results from a neoplastic lesion. 44. The method of claim 43 wherein said neoplastic lesion is caused by a neuroblastoma or a glioma. 45. The method of claim 30 wherein said morphogen stimulates cell adhesion molecule production in a cell defining said pathway. 46. The method of claim 45 wherein said cell adhesion molecule is a nerve cell adhesion molecule. 47. The method of claim 46 wherein nerve cell adhesion molecule is selected from the group consisting of N-CAM-120, N-CAM-140 and N-CAM-180. 48. The method of claim 30 or 45 wherein said morphogen comprises an amino acid sequence sharing at least 70% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-l(fx) and 60A(fx). 49. The method of claim 48 wherein said morphogen comprises an amino acid sequence sharing at least 80% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-l(fx), and 60A (fx). 50. The method of claim 49 wherein said morphogen comprises an amino acid sequence having greater than 60% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 51. The method of claim 50 wherein said morphogen comprises an amino acid sequence having greater than 65% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 52. The method of claim 51 wherein said morphogen comprises an amino acid sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl), including allelic and species variants thereof. 53. The invention of claims 1, 2, 30 or 46 wherein said morphogen comprises a polypeptide chain encoded by a nucleic acid that hybridizes under stringent conditions with the DNA sequence defined by nucleotides 1036-1341 of Seq. Id No. 16 or nucleotides 1390-1695 of Seq. ID No. 20. 54. The invention of claims 1, 2, 26, 30, 45 or 51 wherein said morphogen comprises a dimeric protein species complexed with a peptide comprising a pro region of a member of the morphogen family, or an allelic, species or other sequence variant thereof. 55. The invention of claim 54 wherein said dimeric morphogen species is noncovalently complexed with said peptide. 56. The invention of claims 54 or 55 wherein said dimeric morphogen species is complexed with two said peptides. 57. The invention of claims 54 or 55 wherein said peptide comprises at least the first 18 amino acids of a sequence defining said pro region. 58. The invention of claim 57 wherein said peptide comprises the full length form of said pro region. 59. The invention of claims 54 or 55 wherein said peptide comprises a nucleic acid that hybridizes under stringent conditions with a DNA defined by nucleotides 136-192 of Seq. ID No. 16, or nucleotides 157-211 of Seq. ID No. 20. 60. The invention of claims 54 or 55 wherein said complex is further stabilized by exposure to a basic amino acid, a detergent or a carrier protein. 61. A method of maintaining a neural pathway in a mammal comprising: administering said mammal an effective amount of an agent capable of stimulating production of an endogenons morphogen in a cell defining said pathway. 62. A composition for promoting regeneration of a neural pathway at a site of injury in a mammal, comprising: a biocompatible, a\n vivo bioresorbable carrier suitable for maintaining a protein at a site in vivo, and a morphogen, such that said morphogen, when dispersed in said carrier and provided to said site of injury, is capable of stimulating neural pathway regeneration at said site. 63. The composition of claim 62 wherein said carrier is structurally sufficient to assist direction of axonal growth. 64. The composition of claim 63 wherein said carrier comprises a polymeric material. 65. The composition of claim 63 wherein said carrier comprises laminin or collagen. 66. A device for repairing a break in a neural pathway, the device comprising: a biocompatible tubular casing comprising an exterior and an interior surface and defining a channel through which a neural process may regenerate, said device having a shape and dimension sufficient to span a break in a neural pathway, and having openings adapted to receive the ends of a severed nerve, and a morphogen disposed within the channel defined by said tubular casing and accessible to severed nerve ends defining a break in a neural pathway, such that said morphogen stimulates neural pathway regeneration when disposed in said channel and accessible to said nerve ends. 67. The device of claim 66 wherein said morphogen is disposed in said channel together with a biocompatible, bioresorbable carrier suitable for maintaining a protein at a site q\n vivo. 68. The device of claim 67 wherein said carrier comprises sufficient structure to assist direction of axonal growth within said channel. 69. The device of claim 67 wherein the outer surface of said casing is substantially impermeable. 70. The device of claim 66 wherein said carrier comprises a polymer. 71. The device of claim 67 wherein said carrier comprises laminin or collagen. 72. A method for inducing the redifferentiation of transformed cells of neural origin, the method comprising the step of: contacting said transformed cells with a morphogen composition at a concentration and for a time sufficient to induce redifferentiation of said cells to a morphology characteristic of untransformed neuronal cells. 73. The method of claim 72 wherein said morphology characteristic of untransformed nerve cells includes formation of neurite outgrowths. 74. The method of claim 72 wherein said morphology characteristic of untransformed nerve cells includes cell aggregation and cell adhesion. 75. The method of claim 72 wherein said morphogen composition induces nerve cell adhesion molecule production in said cells. 76. The method of claim 72 wherein said induced nerve cell adhesion molecules include N-CAM-180, N-CAM- 140 and N-CAM-120. 77. The method of claim 72 wherein said transformed cells comprise neuroblastoma cells. 78. A kit for detecting a neuropathy in a mammal or for evaluating the efficacy of a therapy for treating a neuropathy in a mammal, the kit comprising: c) means for capturing a cell or body fluid sample obtained from a mammal; b) a binding protein that interacts specifically with a morphogen in said sample so as to form a binding protein-morphogen complex; c) means for detecting said complex. 79. The kit of claim 78 which said binding protein has specificity for an epitope defined by part or all of the pro region of a morphogen. 80. A method for detecting a neuropathy in a mammal, the method comprising the step of: detecting fluctuations in the physiological concentration of a morphogen present in the serum or cerebrospinal fluid of said mammal, said fluctuations being indicative of an increase in neuronal cell death. l 81. A method for detecting a neuropathy in a mammal, the method comprising the step of: detecting fluctuations in the physiological concentration of a morphogen antibody titer present in the serum or cerebrospinal fluid of said mammal, said fluctuations being indicative of an increase in neuronal cell death. 82. The invention of claims 78, 80 or 81 wherein said neuropathy results from a neurodegenerative disease, nerve demyelineation, myelin dysfunction, neuronal neoplasias, or nerve trauma. 83. A method of stimulating production of cell adhesion molecules in a tissue comprising the step of: providing a morphogen to said tissue for a time and at a concentration sufficient to induce production of cell adhesion molecules in cells of said tissue. 84. The method of claim 83 wherein said cell adhesion molecules comprises nerve cell adhesion molecules. 85. The method of claim 84 wherein said cells comprise neurons. 86. The method of claim 78, 80 or 81 wherein said morphogen comprises an amino acid sequence sharing at least 70% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-1(fx) and 60A(fx). 87. The method of claim 86 wherein said morphogen comprises an amino acid sequence sharing at least 80% homology with one of the sequences selected from the group consisting of: OP-l, OP-2, CBMP2, Vgl(fx), Vgr(fx), DPP(fx), GDF-l(fx) and 60A (fx). 88. The method of claim 87 wherein said morphogen comprises an amino acid sequence having greater than 60% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 89. The method of claim 88 wherein said morphogen comprises an amino acid sequence having greater than 65% amino acid identity with the sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl.) 90. The method of claim 89 wherein said morphogen comprises an amino acid sequence defined by residues 43-139 of Seq. ID No. 5 (hOPl), including allelic and species variants thereof. 91. The method of claim 78, 80 or 81 wherein said morphogen comprises an amino acid sequence encoded by a nucleic acid that hydridizes under stringent conditions with the sequence defined by nucleotides 1036-1341 of Seq. ID No. 16 or nucleotides 1390- 1695 of Seq. ID No. 20. 92. A composition for enhancing survival of neuronal cells at risk of dying comprising a morphogen in association with a molecule capable of enhancing the transport of said morphogen across the blood-brain barrier. 93. The invention of claims 62 or 67 wherein said carrier comprises brain tissue derived extracellular matrix.

Inventors: COHEN CHARLES M, KUBERASAMPATH THANGAVEL, OPPERMANN HERMANN, OZKAYNAK ENGIN, PANG ROY H L, RUEGER DAVID C, COHEN, CHARLES, M., KUBERASAMPATH, THANGAVEL, OPPERMANN, HERMANN, OZKAYNAK, ENGIN, PANG, ROY, H., L., RUEGER, DAVID, C.
Applicants: CREATIVE BIOMOLECULES INC, CREATIVE BIOMOLECULES, INC.
Application year: 1993
Main classification: A61K37
IPC codes: A61F2, A61K6, A61K38, A61K48, A61L27, A61P25, A61P35, A61P43, C07K14, C07K16, C12Q1, G01N33