bluuebunny/crossref_metadata_2025 huggingface dataset:
The oviduct musculature of the cockroach Leucophaea maderae and its response to various neurotransmitters and hormones
Authors: Cook Benjamin J. , Holman G. Mark , Meola Shirlee
Published: February 2005

The musculature of the oviduct consists of an outer, irregular layer of longitudinal muscle and an inner layer of circular muscle. The four basic modes of activity—compression, segmentation, peristalsis, and reverse peristalsis—were evident in the isolated oviduct. These spontaneous events often occurred in an organized sequence. In fact eggs could be transported down the lateral oviducts by this myogenic activity once the sphincter between the common oviduct and vagina was severed. Myographic recordings were made of only the contractions of the longitudinal muscles.

L‐glutamate caused a distinct phasic contraction at 2.2 × 10−5 M. The response became larger and more complex as the concentration of the amino acid was increased. Acetylcholine (1.6 × 10−5 M) caused either a phasic or tonic response, or a combination thereof. By contrast, 5HT and tyramine simply increased the frequency of small phasic contractions, although in some preparations both monoamines caused an inhibition. The ecdysones, a juvenile hormone analogue (1 × 10−6 M), and prostaglandin E2 had no effect on oviduct activity.

Initially high KCI solutions (162 mM) without Ca++ induced a strong contraction but subsequent additions failed to do so. However, when a high KCI solution (158 mM) with 2 mM Ca++ was added to the preparation the response was partially restored. Also the potent calcium antagonist Mn++ (2mM) can suppress spontaneous activity.
Dietary fatty acid effects on morphogenesis in bithorax mutants
Authors: Anastakis D. , Rapport E. , Rogers I.
Published: February 2005

Three bithorax alleles of Drosophila melanogaster were tested to determine if dietary additions of fatty acids would alter their gene expression. For the bx1 allele, myristic, oleic, and linoleic acids were all effective in reducing gene expression while fatty acid supplementation was ineffective with the bx3 and bx34e alleles. For bx1 the nutritionally sensitive period was found to occur in the first 48 h of larval life.
Purification of phenolic compounds and a phenoloxidase from larval cuticle of the red‐humped oakworm, Symmerista cannicosta francl
Authors: Barrett F. Michael
Published: February 2005

A phenoloxidase has been extracted, purified, and characterized from cuticle of last‐instar larvae of the red‐humped oakworm, Symmerista cannicosta. It is a typical tyrosinase (EC 1.10.3.1., o‐diphenol:O2 oxidoreductase), active toward o‐diphenols but not p‐diphenols, inhibited by thiourea and phenylthiourea, with a pH optimum between 6.0 and 7.2. In these respects it resembles enzyme A of C. vicina, one of the few species from which this presumed wound healing enzyme has been purified and characterized.

Hydrolysis of either exuviae or intact cuticle from last instar larvae yielded a number of ketocatechols of which the most abundant, 2‐hydroxy, 3′,4′‐dihydroxyacetophenone, represented 2.9% of the dry weight of head capsule exuviae, 0.3% of exuviae from the remainder of the body, and 4.6% of the dry weight of head capsule cuticle from previously frozen intact larvae. Differences in the type and amount of ketocatechol recovered from these cuticles are described.
Metabolism of Δ0‐, Δ5‐, and Δ7‐Sterols by Larvae of Heliothis zea
Authors: Ritter Karla S.
Published: February 2005

Heliothis zea was reared on artificial diets containing Δ5‐sterols (cholesterol, campesterol, or sitosterol), Δ7‐sterols (lathosterol, epifungisterol, or spinasterol), or Δ0‐sterols (cholestanol, epicoprostanol, campestanol, or sitostanol) in order to determine how different dietary sterols affect the type of sterols present in the tissues of the late‐sixth‐instar larva. Although all of the dietary sterols (except epicoprostanol) supported the growth of the larvae, not all of the sterols were metabolized to the same end products. In each case, at least 80% of the sterols in the tissues of the larvae retained the same nucleus as that of the dietary sterol, indicating that H. zea carries out very little metabolism of ring B of Δ5‐, Δ7‐, and Δ0‐sterols. The larvae dealkylated the Δ5‐, Δ7‐, and Δ0‐alkylsterols to 24‐desalkylsterols, but a greater percentage of the Δ5‐alkylsterols were metabolized in this manner. The sterols present as free sterols in the larva were also present as esterifed sterols which accounted for 2–4% of the total sterols. Therefore, the sterol composition of the tissues of H. zea can be altered by varying the dietary sterols.
Microsomal marker enzymes of Manduca sexta (L) midgut
Authors: Weirich Gunter F. , Adams Jean R.
Published: February 2005

The subcellular distribution of four enzymes (glucose‐6‐phosphatase, phosphodiesterase I, NADPH‐cytochrome c reductase, and p‐nitroanisole O‐demethylase) in the midgut of “wandering” fifth‐instar larvae of the tobacco hornworm, Manduca sexta (L), was determined and the composition of mitochondrial and microsomal pellets was examined by electron microscopy. Most of the glucose‐6‐phosphatase activity and one‐third of the phosphodiesterase I activity were found in the high‐speed supernatant. NADPH‐cytochrome c reductase activity was marginal and O‐demethylase activity was undetectable in the supernatant. The highest specific activities for phosphodiesterase I, NADPH‐cytochrome c reductase, and p‐nitroanisole O‐demethylase were measured in microsomes, but the relative specific activity of phosphodiesterase I was only half that obtained with the latter two enzymes. In all subcellular preparations the relative specific activities of NADPH‐cytochrome c reductase and p‐nitroanisole O‐demethylase were closely correlated. It is concluded that glucose‐6‐phosphatase and phosphodiesterase I are not microsomal marker enzymes in the midgut, but the activities of NADPH‐cytochrome c reductase and p‐nitroanisole O‐demethylase are quantitative measures of microsomal content.
Neuromuscular and hormonal control of post‐eclosion processes in flies
Authors: Fraenkel Gottfried , Su Jack , Zdarek Jan
Published: February 2005

Flies (exemplified by Sarcophaga bullata) expand after eclosion from the puparium by processes of “pulsing” (slow rhythmical abdominal contractions) and “pumping” of air (fast rhythmical contractions of the cibarial pump). Pulsing and pumping are inhibited if a newly eclosed fly is kept in an enclosed space (sand, a glass tube, an empty puparium). This inhibition no longer applies if such flies are injected with either hemolymph from flies 10–15 min old or cAMP, or are confined at the age of 10 min. This suggests a hormonal control of pulsing and pumping. Pumping alone, without pulsing, occurs in flies treated with certain paralyzing agents like ether, tetrodotoxin, bee venom, or “FlyNap,” or have the connectives in the neck cut or interrupted by cauterization. Application of FlyNap or neck cauterization leads to excessive pumping which results in bloating. Expansion by bloating is confined to the soft membranes, leaving sclerites and wings largely unexpanded. The function of pulsing is probably that of “plasticizing” and stretching the cuticle to make it respond to increased steady pressure by air‐pumping. Flies ligated at the proboscis show almost regular pulsing and pumping, but without intake of air, and consequently no expansion. Cuticle (sclerites) and wings, however, become plasticized. Some plasticization occurs even in the absence, or reduction, of pulsing (in a neck‐cauterized fly), brought about by a hormonal process. Eclosion from the puparium is also initiated by a hormonal action. Thus, the following processes during fly emergence are controlled by hormones: eclosion proper, pulsing, pumping, plasticization, and tanning. These hormones are separate entities, with the possible exception of the pulsing/pumping hormone(s).
Ecdysteroid titre and metabolism to novel apolar derivatives in adult female Boophilus microplus (Ixodidae)
Authors: Wigglesworth Kim P. , Lewis David , Rees Huw H.
Published: February 2005

The free ecdysteroid titre determined by radioimmunoassay in adult female Boophilus microplus showed a peak just prior to full engorgement and detachment of the ticks and decreased subsequently to a very low value. In contrast, the titre of polar ecdysteroid conjugates was very low. Ecdysone was the major ecdysteroid at peak titre and was accompanied by much lower levels of 20‐hydroxyecdysone. In newly detached ticks, injected [3H]ecdysone was metabolized primarily (80%) into much less polar compounds, which could be resolved into at least three groups by reversed‐phase h.p.l.c. These [3H] “apolar” metabolites were transferred to the newly laid eggs, where they accounted for the vast preponderance of ecdysteroids, the level of free hormone being low. Hydrolysis of the three groups of compounds with an esterase preparation from porcine liver yielding [3H]ecdysone, together with the release of [3H] ecdysteroid and fatty acids upon alkaline saponification of the compounds, suggests that they are of a fatty acyl ester nature. The chemical transformation of these “esters” into the corresponding acetonide derivatives indicates that the 2‐ and 3‐hydroxyls of ecdysone remain unsubstituted in these compounds. Several tick tissues, including Malpighian tubules, ovaries, gut, and fat body, metabolized [3H]ecdysone in vitro forming the “apolar esters” as major products. The maternal ecdysteroid “esters” may function as storage forms of hormone (presumably hormonally inactive), which could be hydrolysed enzymically during embryogenesis releasing free ecdysteroids. Such enzymic hydrolysis of [3H]ecdysone “esters” by homogenates from developing eggs of B. microplus has been demonstrated.
Characterization of proteolytic enzymes of the midgut and excreta of the biting fly Stomoxys calcitrans
Authors: Borovsky Dov
Published: February 2005

Proteolytic enzymes were characterized in the midgut and the excreta of the stable fly Stomoxys calcitrans (L) with proteins, synthetic substrates, and inhibitors. Inhibition studies suggested trypsinlike activity in sugar‐fed fly midguts, whereas excreta and blood‐fed fly guts exhibited other proteases.

Trypsinlike activity in midguts removed 20 and 30 h after a blood meal increased from 20% to 50% of the total proteolytic enzymes present. Trypsinlike activity was inhibited with human sera, trypsin‐specific inhibitors, and a protein isolated from the stable fly thorax. When human albumin and globulin fractions were incubated with trypsinlike enzymes isolated from the midgut and excreta, the albumin fraction was less inhibitory than the globulin fractions and was readily hydrolyzed by the proteolytic enzymes. These results may indicate that the proteolytic enzymes produce an abortive complex with the globulin fractions of the sera. Such a complex may explain the temporary inhibition of proteolysis by the blood meal.

Soybean trypsin inhibitor fed to stable flies caused 50% inhibition in proteolytic activity in the midguts of sugar‐fed stable flies and 25% inhibition in the midguts of blood‐fed stable flies. Complete inhibition of proteolytic enzyme activity was achieved only in vitro.

pH profiles of proteolytic enzyme activity isolated from the excreta of blood‐fed stable flies indicated that several proteolytic enzymes were excreted.
N‐acetylglucosaminyl transferases from the pupal instar of the stable fly, Stomoxys calcitrans
Authors: Mayer Richard T. , Chen Andrew C.
Published: February 2005

N‐acetylglucosaminyl transferases from pupae of Stomoxys calcitrans (L.) were studied in 10,000g pellet suspensions. Characterization of these enzymes was based on formation of glycolipids (ie, Dol·PP‐GlcNAc and Dol·PP‐(GlcNAc)2), oligosaccharide lipids, and giycoproteins. Studies on transferase activity during the pupal instar showed that there were two peaks of activity; the first peak was on day 0 (prepupae) and the second at 3 days after pupation. Subcellular fractionation indicated that 10,000g and 100,000g pellets contained most of the transferase activities. The transferases required divalent cations (either Mn2+ or Mg2+). The pH optimum, which varied for each of the products formed, was 7.5 for glycolipids, 7.0 for oligosaccharide lipids, and 6.5 for glycoprotein. Inclusion of dolichol monophosphate doubled the amount of Dol·PP‐GlcNAc and Dol·PP·(GlcNAc)2 formed, but had little effect on oligosaccharide lipid and glycoprotein formation.

Tunicamycin was a potent inhibitor of glycolipid formation with an I50 of 1.8–4.8 nM. It was confirmed that tunicamycin acts by preventing the transfer of GlcNAc‐1‐P from UDP‐GlcNAc to Dol·P. UMP reverses glycolipid formation, yielding UDP‐GlcNAc. Some characterization of the products was performed. Glycolipids were shown to be Dol·PP‐GlcNAc and Dol·PP‐(GlcNAc)2. Glycoprotein was rapidly solubilized by protease and detergent treatments, whereas oligosaccharide lipids appeared to be acid‐labile, pyrophosphate‐containing lipids. The apparent kinetic constants for the formation of glycolipids were as follows: UDP‐GlcNAc Km = 1.55 ± 0.47 μM, Vmax = 0.66 ± 0.21 pmol·min−1·mg−1; Dol·P Km = 2.08 ± 0.85 μM, Vmax = 0.13 ± 0.06 pmol·min−1·mg−1 protein.
Binding of [3H]phencyclidine to membranes from housefly thoracic muscles
Authors: Filbin Marie T. , Eldefrawi Mohyee E. , Eldefrawi Amira T.
Published: February 2005

The binding of [3H]phencyclidine ([3H]PCP) to a preparation of housefly thoracic muscle membranes was studied. Specific [3H]PCP binding saturated with both time and at concentrations of the radiolabeled ligand greater than 20 nM. One binding site with a KD of 10.7 nM and a Bmax of 3.9 pmol/mg protein was observed. Specific [3H]PCP binding was also readily reversible with a half‐time of dissociation (t1/2) of 13.8 min and varied proportionately with tissue concentration. Of the drugs tested, specific [3H]PCP binding was inhibited by PCP analogs, antipsychotics, antidepressants, Ca2+ channel antagonists, and K+ channel blockers. [3H]PCP binding was unaffected by addition of carbamylcholine or L‐glutamate in absence or presence of ATP, GTP, cAMP, or cGMP. Though the identity of the [3H]PCP binding protein in housefly muscle membranes is still unclear, it is more likely to be an ionic channel such as K+ or Ca2+ channels than a neurotransmitter receptor.
Effects of octopamine on fluid secretion by isolated salivary glands of a feeding ixodid tick
Authors: Pannabecker Tom , Needham Glen R.
Published: February 2005

Octopamine elicited a dose‐related secretory response by salivary glands isolated from the feeding female tick Amblyomma americanum. Half‐maximal stimulation occurred at about 60 μM. Phentolamine (10 μM) failed to inhibit the octopamine‐mediated response; however, thioridazine (50 μM) inhibited both octopamine (1,000 μM) and dopamine‐stimulated (0.1 μM) secretion. Maximal stimulation by dopamine (1.0 μM) showed no further increase in the rate of secretion after adding octopamine (1,000 or 0.1 μM). Glands responded to octopamine (100 μM) with rates significantly lower than controls following exposure to amphetamine (1,000 μM). Octopamine receptors do not appear to mediate the secretory response, and octopamine may stimulate secretion by releasing catecholamines from presynaptic neurons. These results support the hypothesis that dopamine is the natural transmitter mediating fluid secretion in the feeding tick salivary gland.
Synthesis and deposition of chitin in larvae of the Australian sheep blowfly, Lucilia cuprina
Authors: Retnakaran A. , Hackman R. H.
Published: February 2005

Chitin synthesis in third‐instar Lucilia cuprina larvae cultured at 23 °C was investigated using in vivo and in vitro systems, the latter with whole and with homogenized integuments. Synthesis was at a maximum between 24 and 48h after ecdysis from the second instar. Chitin was deposited in layers, and labeled GlcNAc was rapidly cleared from the hemolymph. In in vitro homogenate systems, the rapid conversion of UDP‐([14C]GlcN)Ac to ([14C]GlcN)Ac and its 1‐phosphate derivative contributed to the low incorporation of this precursor into chitin. The extent of the conversion was reduced by the addition of KCN or phenylthiourea. In in vivo and in vitro tissue systems the level of incorporation of ([14C]ClcN)Ac was higher than that of UDP‐([14C]GlcN)Ac. However, in in vitro homogenate systems there was no difference unless UTP was added when the level of incorporation of only ([14C]GlcN)Ac was increased (by a factor of 9). Incorporation of UDP‐([14C]GlcN)Ac, but not that of ([14C]GlcN)Ac, was decreased when larvae were deprived of food. Soluble oligosaccharides were detected in in vitro homogenate systems. They were formed during chitin synthesis and may represent newly initiated chitin chains. A reappraisal of current ideas on chitin synthesis in insects is needed.
Purification and partial characterization of mosquito egg development neurosecretory hormone: Evidence for gonadotropic and steroidogenic effects
Authors: Borovsky Dov , Thomas Billy R.
Published: February 2005

Egg development neurosecretory hormone (EDNH), a hormone that stimulates vitellogenesis in mosquitoes, was purified 10,000‐fold from the mosquito Aedes aegypti. The purification procedure included chromatography on hydrophobic, ion exchange, and gel filtration columns, and preparative electrophoresis to give an almost homogeneous preparation. The hormone is a polypeptide monomer of molecular weight of 18,700 ± 500 as determined from SDS electrophoresis and gel filtration chromatography. Using lowpressure chromatography throughout the purification procedure, the hormone was recovered at a high yield (39%). The amount of EDNH in a mosquito is about 0.6‐1.6 ng, corresponding to 32–85 fmol.

Injection of purified EDNH into female mosquitoes resulted in the conversion of [14C]cholesterol into labeled ecdysone and 20‐hydroxyecdysone which were separated and identified using thin‐layer chromatography and high‐performance liquid chromatography separation procedures.

Egg development and vitellogenin synthesis were also induced when EDNH was injected into several mosquito species, indicating that the hormone is not species‐specific.

This report is the first to show that a purified preparation of EDNH has both steroidogenic and a gonadotropic effects on female mosquitoes.
Isolation of an agent affecting the development of an internal parasitoid
Authors: Hotchkin Phyllis G. , Kaya Harry K.
Published: February 2005

The development of an internal braconid parasitoid, Glyptapanteles militaris, is adversely affected when its host, Pseudaletia unipuncta, is infected with the Hawaiian strain of granulosis virus. A plasma‐derived agent, isolated from virus‐infected hosts, was shown to elicit developmental aberrations in the parasitoid similar to those observed in virus‐infected hosts. This agent was isolated by ammonium sulfate precipitation, gel filtration, and anion exchange chromatography, and its molecular weight, established by gel filtration and SDS‐polyacrylamide gel electrophoresis, was determined to be about 64,000. The dilution end point of the agent and some stability properties were also established.
Identification of male‐specific exocrine secretions from predatory stink bugs (Hemiptera, pentatomidae)
Authors: Aldrich J. R. , Oliver J. E. , Lusby W. R. , Kochansky J. P.
Published: February 2005

In the nearctic predaceous stink bugs (Asopinae), Perillus bioculatus and Stiretrus anchorago, and the neotropical asopine, Oplomus severus, males possess conspicuous sternal glands that are absent in females. In each of these species, the male sternal gland secretion contains predominantly a single compound; 6,10,13‐trimethyltetradecyl isovalerate in the allopatric species, P. bioculatus and O. severus, and 6,10,13‐trimethyltetradecanol in S. anchorago, a species sympatric with P. bioculatus. The function of the sternal gland secretions from asopine hemipterans is unknown.
Feedback inhibition of ecdysone production by 20‐hydroxyecdysone during pupal—adult metamorphosis of Mamestra configurata wlk
Authors: Bodnaryk Robert P.
Published: February 2005

Large peaks of ecdysone (E, 2,875 ng/g live wt) and 20‐hydroxyecdysone (20‐HE, 2,150 ng/g live wt) occur on days 8 and 12, respectively, of postdiapause pupal‐adult metamorphosis at 20°C in the bertha armyworm, Mamestra configurata, and then decline to low levels (< 100 ng/g live wt) prior to eclosion of the moth (50% eclosion at day 31.8). These peaks of E and 20‐HE can be suppressed by treating the developing pupae with a physiological dose (2,500 ng/g live wt) of 20‐HE. Suppression of E and 20‐HE by 20‐HE treatment was dose dependent, rapid (within 24 h of treatment) and permanent. The peaks of E and 20‐HE were suppressed by 20‐HE treatment on days 1, 3, 5, and 7 but the 20‐HE peak was not suppressed by treatment on days 9 or 11.

It is proposed that the mechanism by which 20‐HE suppresses the production of E and thereby its own production forms a negative feedback loop that operates during the first 0.4 units of pupal‐adult development in M. configurata. The function of the transitory peaks of E and 20‐HE that form this feedback loop is currently unknown. Since most adults from pupae that had their ecdysteroid levels experimentally suppressed by 20‐HE treatment were morphologically normal, it seems that the peaks of E and 20‐HE have little or no function in controlling morphological development in pupae of M. configurata.
Cuticular lipids for species recognition of mole crickets (Orthoptera: Gryllotalpidae): II. Scapteriscus abbreviatus, S. acletus, S. vicinus, S. sp., and Neocurtilla hexadactyla
Authors: Castner James L. , Nation James L.
Published: February 2005

Qualitative analyses were made from whole‐body cuticular extracts of Scapteriscus abbreviatus, Scapteriscus acletus, Scapteriscus vicinus, and Neocurtilla hexadactyla by isothermal and temperature‐programmed gas chromatography. Adults of both sexes and nymphs of each species were collected in Florida. The chromatographic profiles of peaks were distinct and easily recognizable for each species, regardless of sex or developmental stage. Distinct sexual differences were found in S. acletus and S. abbreviatus. Specimens of S. abbreviatus from Puerto Rico and S. vicinus from Bolivia produced gas chromatography (GC) traces very similar to those of conspecifics collected in Florida. Evidence is presented to illustrate the potential importance of volatile cuticular lipid analysis as a tool for mole cricket identification. Cuticular extracts of an undescribed short‐winged species of Scapteriscus from Bolivia were also examined and produced GC traces unlike those of any other species analyzed to date.
Isolation and characterization of Brush border fragments from mosquito mesenterons
Authors: Houk Edward J. , Arcus Yvonne M. , Hardy James L.
Published: February 2005

Brush border fragments were isolated from homogenates of mesenterons from the mosquito, Culex tarsalis, by a combination of Ca2+ precipitation and differential centrifugation. These preparations were routinely enriched seven‐ to eightfold for the brush border marker enzyme, leucine aminopeptidase. Alkaline phosphatase, a putative brush border marker for both vertebrate and invertebrate brush borders, was found to be unsuitable for Cx. tarsalis. Isoelectric focusing electrophoresis coupled with histochemical enzyme detection was used to enumerate isozymic species of nonspecific esterases [3], leucine aminopeptidase [1], and alkaline phosphatase [1] in isolated brush border fragments. Leucine aminopeptidase activity was solubilized by papain digestion, suggesting an extrinsic active site for this membrane‐bound enzyme. The predominant nonspecific esterase isozyme remained membrane‐bound. Conventional staining (ie, Coomassie Blue and silver) of proteins separated by isoelectric focusing, sodium dodecylsulfate, and two‐dimensional electrophoresis indicated a simple pattern for brush border fragments, with two proteins predominating among the 11–14 routinely detected.
Ecdysteroids in Developing ovarian follicles of Hyalophora cecropia
Authors: Rubenstein Elaine C. , Kelly Thomas J. , Culbert Laura , Woods Charles W. , Weeks Benjamin
Published: February 2005

Developing ovarian follicles of the silkmoth Hyalophora cecropia accumulate large amounts of ecdysteroids during oogenesis. As measured by an ecdysteroid radioimmunoassay (RIA), this accumulation begins near the end of vitellogenesis, just prior to nurse cell collapse, and continues through the beginning of chorion formation. Analysis of ovarian ecdysteroids by a combination of high‐performance liquid chromatography and RIA demonstrates that the major proportion of these are present in a highly polar form, most likely as conjugates; ecdysone and 20‐hydroxyecdysone were present as well, in much lower proportions. Light microscopic autoradiographs of photoactivated follicles after in vivo incubation with [3H]ecdysone indicate that within the oocyte ecdysteroids are associated with the yolk sphere membranes.
Qualitative and quantitative changes in hemolymph proteins during an ovarian cycle and after insemination in Thermobia domestica (packard) (thysanura, lepismatidae)
Authors: Rousset André , Lapalisse Jacques
Published: February 2005

Qualitative and quantitative investigations on the hemolymph proteins in the adult firebrat Thermobia domestica were performed during an ovarian cycle in inseminated and noninseminated females. Variations of hemolymph protein concentration were determined by Lowry's method. In addition, the proteins were studied by gradient slab gel electrophoresis using nondenaturing conditions and microdensitometry. Besides five major protein fractions, which are present in both sexes, three female‐specific protein bands (vitellogenins) are found in the hemolymph and in maturing oocytes. These vitellogenins have molecular masses of 430, 300 and 240 kiloDalton. In fact, associated with the main 300‐kD band, there were two smaller bands (320 and 280 kD) indistinguishable by densitometric measurement. Quantitative changes of vitellogenins are linked to oocyte maturation. These proteins appeared in the hemolymph before ecdysis, at the same time as the first yolk granules in the basal oocytes. They increased after ecdysis during the intense vitellogenic phase and decreased during chorion formation. In noninseminated females, in which all maturing oocytes are resorbed before chorion formation, the level of the 300 kD vitellogenins remained lower than in inseminated females. The quantity of vitellogenins fell only after complete oosorption. Thus insemination caused changes in the relative quantities of the different vitellogenic proteins.
Isolation and in vitro synthesis of trypsin from the biting fly, Stomoxys calcitrans
Authors: Borovsky Dov
Published: February 2005

The synthesis of [3H]trypsinlike enzyme by the fat body was followed in Stomoxys calcitransin vitro using a radioimmunoassay (RIA) developed against mammalian trypsin. Using high specific activity [3H]valine, trypsinlike activity was followed in midgut epithelial cells, thoracic muscle, and fat body removed from sugar‐fed flies. Excreta protease of S. calcitrans was partially purified using charge and hydroxylapatite gel chromatography. Seventy‐five percent of the enzyme eluted from these gels was inhibited by tosyl‐L‐lysine chloromethyl ketone HCI (TLCK) and was classified as trypsinlike. Electrophoresis of the trypsinlike enzyme indicated that it was only 50% pure. Trypsinlike activity from S. calcitrans bound to α1‐globulin IV‐I and formed a complex that was dissociated on a P‐100 Bio‐Gel column. Binding between the protease and the α1‐gobulin IV‐I caused a 1.4‐fold increase in the apparent molecular weight of the protease on the P‐100 Bio‐Gel column. Trypsinlike activity was characterized in the midgut and excreta by affinity binding to covalently linked TLCK and tosyl‐L‐lysine chloromethyl ketone HCI (TAME)Sepharose 4B gels. Between 50% and 55% of the excreta protease and 5669% of the midgut protease bound to the affinity gels and was trypsinlike. Protease activity that did not bind to the gels was not inhibited by TLCK and did not have the esterolytic activity of trypsin.
[N‐Methyl‐3H]Scopolamine binding sites in the central nervous system of the cockroach Periplaneta americana
Authors: Lummis Sarah C. R. , Sattelle David B.
Published: February 2005

The binding of [N‐methyl‐3H]scopolamine to a cockroach nerve cord preparation has been investigated. Specific [N‐methyl‐3H]scopolamine binding was found to be saturable and of high affinity (Kd = 13.9 nM). Muscarinic ligands were found to displace [N‐methyl‐3H]scopolamine binding more effectively than nicotinic ligands. The distribution of these [N‐methyl‐3H]scopolamine binding sites was examined in the metathoracic ganglion at the light microscope level by autoradiographical techniques. Specific binding was found to be localized to distinct regions of the neuropile. This pattern showed certain similarities to that seen when the ganglion was stained for acetylcholinesterase, suggesting a functional role for these insect muscarinic acetylcholine receptors.
Utilization of Δ5,7 ‐ and Δ8‐sterols by larvae of Heliothis zea
Authors: Ritter Karla S.
Published: February 2005

Larvae from two populations of Heliothis zea were reared on artificial diets containing various sterols, which supported suboptimal growth, and their tissue sterols were characterized in order to determine how these dietary sterols are utilized by this insect. The sterols studied included Δ5,7‐sterols (7‐dehydrocholesterol or ergosterol), Δ8‐sterols (lanosterol and/or 24‐dihydrolanosterol), and a Δ5‐sterol (4,4‐dimethylcholesterol). Although larvae did not develop on 4,4‐dimethylcholesterol, those fed primarily Δ8‐4,4,14‐trimethylsterols developed to the third instar. When the latter sterols were spared with cholesterol, the larvae reached the sixth instar and contained 4,4,14‐trimethylsterols as well as cholesterol in their tissues. When larvae were fed 7‐dehydrocholesterol, <1% of the larvae from one population developed to the sixth instar and these larvae contained 7‐dehydrocholesterol as their principal sterol. The other larvae successfully completed their larval stage when they were transferred from the diet containing 7‐dehydrocholesterol (or no sterol) to a diet containing cholesterol within at least 9 days. The sterol composition of larvae transferred from a diet containing cholesterol to a diet containing 7‐dehydrocholesterol, after they had reached 60% of their final weight, was 54% cholesterol and 46% 7‐dehydrocholesterol. The major sterol isolated from the tissues of the larvae fed ergosterol was also 7‐dehydrocholesterol. Therefore, although the larva of H. zea can dealkylate and saturate the side chain of the Δ5,7,22‐24β‐methylsterol, it carries out little metabolism of the B ring of the nucleus. These studies demonstrate that, when Δ5,7‐ or Δ8‐sterols are the principal sterols in the diet of H. zea, they are absorbed and incorporated into its tissues, although they slow the rate of growth and may prevent complete development of the larva.
Presence and regulation of trehalose in the body of adult Phormia regina
Authors: Anelli Carol M. , Friedman Stanley
Published: February 2005

Trehalose, the major blood sugar of Phormia regina, is present within its tissues in an amount exceeding that in the total blood volume. A major part of the reserve is found in the abdominal fat body. An investigation of trehalose regulation, pursued with the use of a trehalose tolerance test, indicates that within a period of 4 h the adult fly can remove from its blood amounts of this sugar in excess of twice its normal level. The surplus is dealt with in an as yet unknown way, being either sequestered in the tissues (not as trehalose or glucose), metabolized, or excreted in a form other than trehalose or glucose. The process is regulated by the head, and a link between the body and the head must be maintained throughout the entire period of activity.
Larval development, developmental arrest, and hormone levels in the couple Galleria mellonella (lepidoptera‐pyralidae)—Pseudoperichaeta nigrolineata (diptera‐tachinidae)
Authors: Plantevin G. , Grenier S. , Richard G. , Nardon C.
Published: February 2005

During their growth on the substitution host Galleria mellonella, about onethird of Pseudoperichaeta nigrolineata larvae undergo a developmental arrest in the middle of the second stage. To assess the extent of endocrine involvement, juvenile hormone (JH) and ecdysteroid (ECD) determinations by radioimmunoassays were made both on G. mellonella and P. nigrolineata throughout the larval development of this parasitoid. The transfer of G. mellonella larvae from the usual rearing temperature (27.5°C) to that required for infestation (21°C) significantly affects hormone titers: the JH level increases 10 to 20 times, while the ECD level becomes 10 times lower. The JH levels are lower in hosts with parasitoids in developmental arrest than in those with P. nigrolineata in continuous growth, but the high variability makes it seem unlikely that the titer of this hormone is critical in regulating development of the parasitoid. ECD levels are depressed in the hosts with parasitoids in developmental arrest and are increased when the parasitoids resume growth. Therefore, we propose that the main cause of the developmental arrest of P. nigrolineata is the low ECD levels characterizing some G. mellonella larvae for which the transfer to 21°C has induced some physiological disturbances.
Disinhibition of oocyte growth in adult, virgin Periplaneta americana by corpus allatum denervation: Age dependency and relatedness to mating
Authors: Pipa Rudolph
Published: February 2005

Unilateral section of the nervi corporis allati I (NCA‐1) of isolated, starved, adult, virgin Periplaneta americana disinhibited oocyte growth during a specific period following their adult emergence. The effect required that the corpus allatum (CA) be free of NCA‐1 innervation for 4 days beyond the time the females were 7–8 days old. The onset of this sensitive period corresponds to when most isolated, starved virgins become sexually receptive. The results suggest that NCA‐1 inhibition of CA activity, initiated about 7 days, is relieved by mating. When done on sexually receptive, starved virgins, unilateral NCA‐1 section was as effective as insemination for stimulating growth and chorionation of the first generation of oocytes. Neural inhibition of juvenile hormone (JH) secretion by the CA may also explain diminished production of oocytes by isolated, fed virgins, for during 30 days following unilateral NCA‐1 section they produced 2.6 to 5 times more oothecae than did controls with a single CA removed or after the sham operation. The number of oothecae deposited by fed virgins was similarly increased after bilateral NCA‐1 section, but to a lesser extent than when the operation was done on fed, inseminated females of the same age.

Specificity of the response of the CA to denervation was substantiated by experiments in which the CA were extirpated and reimplanted, by topically applying C16JH, and by experiments in which the nervus corporis cardiaci 1 and 2 on the right or left side were severed.
Effect of conditioned media on three genotypes of Drosophila melanogaster: Physical, chemical, and biological aspects
Authors: Castro J. A. , Botella L. M. , Ménsua J. L.
Published: February 2005

The uric acid contents in larvae, pupae, and culture media were studied during larval and pupal development in three genotypes of Drosophila melanogaster reared in both crowded and noncrowded conditions. The uric acid content and the response of genotypes in media supplemented with 10 and 15 mg/ml of uric acid were correlated with the outcome obtained in conditioned media. In addition, the behavior of genotypes in conditioned media is explained in terms of the physicochemical properties of the conditioned media, which include uric acid content, the amount of food ingested, the degree of free water, the physical disturbance within the cultures, and the particular response of each genotype to uric acid.
Studies on binding and uptake of vitellogenin by follicles of the tobacco hornworm, Manduca sexta
Authors: Osir Ellie O. , Law John H.
Published: February 2005

An in vitro system for the uptake of 125l‐vitellogenin (VG) or vitellin into isolated follicles of the tobacco hornworm, Manduca sexta, is described. After incubation with 125l‐VG, follicles were disrupted and the internal yolk contents separated from the follicle membranes. The results showed that 125l‐VG was associated principally with the membranes (92%) after incubation at 4°C. However, at 27°C, 125l‐VG was mainly in the yolk (92%). Furthermore, trypsin treatment removed approximately 70% of VG bound to the follicles at 4°C. Labeled VG was shown to bind to sonicated follicle membranes with high specificity and affinity (KD ⋍ 1.3 × 10−8 M). This binding was sensitive to pH and calcium concentration. The total binding sites were estimated at 4 × 1014 sites/g of membrane protein. Competition studies showed that binding of 125l‐VG to follicle membranes was blocked by excess unlabeled vitellin and deglycosylated vitellogenin but not by lipophorin (the major hemolymph lipoprotein), microvitellogenin, a female‐specific protein (Mr ∼ 31,000) found in both hemolymph and eggs, and the smaller vitellogenin subunit, apovitellogenin‐II (Mr ∼ 45,000). These results suggest that selective uptake of M. sexta VG from the hemolymph involves binding to specific receptors located on the follicle membranes.
Neural correlates of flight activation and escape behavior in houseflies recovering from pyrethroid poisoning
Authors: Bloomquist J. R. , Miller T. A.
Published: February 2005

Recovery from pyrethroid poisoning was studied in groups of adult female houseflies treated with LD50 doses of trans‐permethrin or deltamethrin. The first overt sign of recovery was the appearance of normal posture, which was followed by jumping behavior and finally, coordinated flight when the flies had fully recovered. Prior to full recovery, treated houseflies were able to maintain normal posture and usually jump, but they could not fly. When tethered, these flightless houseflies responded to loss of tarsal contact by initiating normal patterned activity in the dorsolongitudinal flight muscles, yet the wings did not move. In flightless flies displaying jumping behavior, electrical stimulation of the brain evoked responses in the pleurosternal muscle, which controls thoracic tension during flight. Thus, many of the motor systems responsible for flight behavior seemed to be functional in flightless flies. Carbofuran, a carbamate anticholinesterase known to initiate spontaneous flight behavior from within the central nervous system, failed to elicit this response in flightless flies. These results suggested that the flightless condition was due to a disruption in central nervous pathways, and not to peripheral neuromuscular block. The pattern of recovery of different behaviors analyzed in this study was found to be consistent with the Jacksonian Hierarchy Principle, and the utility of this principle in guiding the design of new behavior‐modifying compounds is discussed.
Partial characterization of a major gut thiol proteinase from larvae of Callosobruchus maculatus F.
Authors: Kitch L. W. , Murdock L. L.
Published: February 2005

Much of the proteolytic activity in the digestive tract of Callosobruchus maculatus larvae can be attributed to a thiol proteinase(s) that hydrolyzes [3H]methemoglobin optimally at pH 5.0. Maximal hydrolysis of [3H]methemoglobin, [3H]alpha‐casein, and N‐benzoyl‐DL‐arginine napthylamide‐(BANA) required the presence of thiol reducing agents. Larval gut proteinase activity was strongly inhibited by p‐hydroxymercuribenzoic acid (pHMB), Nethylmaleimide (NEM), and iodoacetic acid (IAA) but was unaffected by the Bowman‐Birk and Kunitz proteinase inhibitors from soybeans or by lima bean trypsin inhibitor. L‐Trans‐epoxysuccinyl‐leucylamido‐(4‐guanidino)‐butane (E‐64), a specific inhibitor of thiol proteinases, potently inhibited proteolysis of [3H]methemoglobin by larval gut homogenates. Proteolytic activity in the larval gut was located in the lumen contents and thus appears to play a major role in extracellular digestion. The pH of the larval midgut is slightly acidic, and midgut contents exhibit a negative redox potential, conditions supporting the activity of a thiol proteinase. The significance of these findings is discussed with reference to the vulnerability of this digestive proteinase as a target for existing or genetically engineered plant chemical defenses.
The polypeptide structure of Vitellogenin and Vitellin from the cockroach, Leucophaea maderae
Authors: Brookes Victor J.
Published: February 2005

Vitellogenin (Vg) synthesized by the fat body of Leucophaea maderaeis made up of four polypeptides with molecular weights of 160,000, 105,000, 98,000, and 57,000. Other polypeptides previously reported as part of Vg are associated with other proteins. Vitellin (Vt), the yolk protein (YP) isolated from mature oocytes and from newly formed oothecae, is a protein with a sedimentation coefficient of 28s and consists of three polypeptides with molecular weights of 105,000, 85,000, and 57,000. During vitellogenesis, the YP of developing oocytes contains both Vt and a 14s component. The 14s component is made up of four polypeptides with molecular weights of 105,000, 90,000, 85,000, and 57,000. The data suggest that 14s may not be a discrete protein but rather a form in transition between Vg and Vt in which the 98,000 dalton polypeptide is converted to the 85,000 dalton polypeptide of Vt through a 90,000 dalton intermediate. The 160,000 dalton peptide of Vg does not appear to be a part of Vt. Under alkaline conditions, both the 14s component and Vt are reduced to a polypeptide with a lower sedimentation rate in sucrose gradients. When acid conditions are restored, a protein resembling 14s is obtained. This suggests that the YP is a loosely held aggregate of similar or identical proteins with a molecular weight of about 250,000.
Hormonal control of locust oviducts
Authors: Lange Angela B.
Published: February 2005

The oviducal muscles of the locust, Locusta migratoria, contract in a spontaneous and rhythmic fashion when isolated from the central nervous system. Hemolymph of ovipositing females, when added to isolated locust oviducts, altered the spontaneous contractility of the oviduct. This response was not evident after addition of hemolymph from a nonovipositing female and was still present after addition of the α‐aminergic receptor antagonist, phentolamine.

Oviducts in which mature eggs were present responded to homogenates of the corpus cardiacum by increasing both the frequency and amplitude of muscular contraction, whereas oviducts devoid of eggs showed no response. Extracts of ventral nerve cord also increased the spontaneous activity of the oviduct musculature. Although the muscles of the oviduct responded to homogenates of the brain, this response differed in two ways from the response due to corpus cardiacum homogenates. First, oviducts devoid of mature eggs responded to brain homogenates; and second, the response caused by the brain homogenates could be eliminated by the addition of 1 μM phenoxybenzamine. The significance of these results is discussed.
Posteclosion behavior of the flesh fly, Sarcophaga crassipalpis: A comparison of wild‐type and unicorn mutants
Authors: Žďárek Jan , Denlinger David L.
Published: February 2005

Newly emerged flies go through a stereotypic behavioral pattern of walking, grooming, abdomen contraction (pulsing), and active uptake of air (pumping). These behavioral activities can be readily distinguished on the basis of hemolymph pressure changes. Wild‐type flies and a unicorn mutant that fails to properly retract its ptilinum show identical patterns of posteclosion activity. However, a portion of the unicorns do not fully expand their wings and abdomen. Such flies are missing only the pumping component of the normal behavioral repertory, thus implying that pulsing and pumping are independently controlled.
Ecdysone metabolism in Pieris brassicae during the feeding last larval instar
Authors: Beydon Philippe , Girault Jean‐Pierre , Lafont René
Published: February 2005

Ecdysone metabolism in Pieris brassicae during the feeding last larval stage was investigated by using 3H‐labeled ecdysteroid injections followed by high‐performance liquid chromatographic (HPLC

Abbreviations: 3DE = 3‐dehydroecdysone; 3D20E = 3‐dehydro‐20‐hydroxyecdysone; 2026E = 20,26‐dihydroxyecdysone; E = ecdysone; Eoic = ecdysonoic acid; 2026E′ = 3‐epi‐20,26‐dihydroxyecdysone; E′ = 3‐epiecdysone; E′oic = 3‐epiecdysonoic acid; E′8P = 3‐epiecdysone 3‐phosphate; 20E′ = 3‐epi‐20‐hydroxyecdysone; 20E′3P = 3‐epi‐20‐hydroxyecdysone 3‐phosphate; FT = Fourier transform; HPLC = high‐performance liquid chromatography; 20E = 20‐hydroxyecdysone; 20Eoic = 20‐hydroxyecdysonoic acid; NMR = nuclear magnetic resonance; NP‐HPLC = normal phase HPLC; RP‐HPLC = reverse phase HPLC; TFA = trifluoroacetic acid; Tris = tris(hydroxymethyl)‐aminomethane.

) analysis of metabolites. Metabolites were generally identified by comigration with available references in different HPLC systems. Analysis of compounds for which no reference was available required a large‐scale preparation and purification for their identification by 1H nuclear magnetic resonance spectrometry.

The metabolic reactions affect the ecdysone molecule at C‐3, C‐20, and C‐26, leading to molecules which are modified at one, two, or three of these positions. At C‐20, hydroxylation leads to 20‐hydroxyecdysteroids. At C‐26, hydroxylation leads to 26‐hydroxyecdysteroids which can be further converted into 26‐oic derivatives (ecdysonoic acids) by oxidation. At C‐3, there are several possibilities: there may be oxidation into 3‐dehydroecdysteroids, or epimerization possibly followed by phosphate conjugation.

Thus, injected 20‐hydroxyecdysone was converted principally into 20‐hydroxyecdysonoic acid, 3‐dehydro‐20‐hydroxyecdysone, and 3‐epi‐20‐hydroxyecdysone 3‐phosphate. Labelled ecdysone mainly gave the same metabolites doubled by a homologous series lacking the 20‐hydroxyl group.
Carbohydrate metabolism in starved fifth instar larvae of Manduca sexta
Authors: Siegert Karl J.
Published: February 2005

The influence of starvation on carbohydrate metabolism in fifth instar larvae of Manduca sexta was studied. The percentage of active fat body glycogen phosphorylase increased from 10% to approximately 50% within 3 h of starvation; afterward the enzyme was slowly inactivated. The increase of phosphorylase activity might have been caused by a peptide(s) from the CC. The amount of fat body glycogen in starved animals decreased over 24 h by approximately 20 mg. The released glucose molecules seem to be converted mainly to trehalose because the hemolymph trehalose concentration in starved animals was always slightly higher than in the fed controls, and the glucose concentration decreased even when phosphorylase was activated. The chitosan content in starved larvae increased during the first 9 h of treatment to the same extent as in fed controls. It is suggested that fat body glycogen phosphorylase was activated during starvation to provide substrates for chitin synthesis and energy metabolism.
Synthesis of proteins and nucleic acids by the pea aphid Acyrthosiphon pisum (aphididae) in the absence of a full complement of dietary amino acids
Authors: Srivastava P. N. , Srivastava U. , Thakur M. , Auclair J. L.
Published: February 2005

Protein, nucleic acids, and nucleotide syntheses were studied in pea aphids, Acyrthosiphon pisum (Harris), by feeding them labeled 14C‐amino acids and [5‐3H]‐orotic acid in sucrose. It was demonstrated that in the absence of dietary essential amino acids, aphids were capable of synthesizing nucleic acids, nucleotides, and proteins when provided with a single dietary amino acid in sucrose. It is suggested that other required amino acids were possibly supplied by the symbionts present in the pea aphid and/or were obtained from the amino acid pool in the hemolymph or glucose, one of the end products of sucrose digestion. Of the various amino acids tested, synthesis of measurable amounts of protein or other compounds occurred when alanine, aspartic acid, glutamic acid, glycine, proline, or serine were provided, but no synthesis occurred with cysteine.