bluuebunny/crossref_metadata_2025_split huggingface dataset:
Primer and interview: Epithelial to mesenchymal transition
Authors: Kiefer Julie C. 
Published: September 2008

AbstractA complex body plan would not be possible without the evolution of the epithelial to mesenchymal (EMT) transition. This primer introduces the hallmarks of EMT, molecular mechanisms underlying the process, and its role in development and disease. Accompanying the primer is a discussion of current topics in the field with EMT experts Angela Nieto, Ph.D., and Jean Paul Thiery, Ph.D. Developmental Dynamics 237:2769–2774, 2008. © 2008 Wiley‐Liss, Inc.
Baf60c is a component of the neural progenitor‐specific BAF complex in developing retina
Authors: Lamba Deepak A. , Hayes Susan , Karl Mike O. , Reh Thomas 
Published: September 2008

AbstractRemodeling of the chromatin network plays an important role regulating embryonic development as well as differentiation. The SWI/SNF complex is an ATP‐dependent chromatin‐remodeling complex. It consists of several proteins, including an ATPase subunit, either Brg1 or Brm. Two subunits of this complex, Baf53a and Baf45, have been previously identified as being neural progenitor‐specific. In this study, we show that Baf60c, another important part of this large complex, acts in a similar neural progenitor–specific manner. We show that during development Baf60c is expressed in neural progenitors in human retinas as well as mouse retina, cortex and spinal cord. Baf60c expression is lost during neural differentiation and its overexpression keeps the progenitors in a proliferative state through its interaction with the Notch pathway. Finally, we show that Baf60c is re‐expressed in the Müller glial cells that re‐enter the cell cycle after neurotoxic damage. Developmental Dynamics 237:3016–3023, 2008. © 2008 Wiley‐Liss, Inc.
Androgen receptor gene expression in the developing and adult zebrafish brain
Authors: Gorelick Daniel A. , Watson William , Halpern Marnie E. 
Published: September 2008

AbstractAndrogens play a central role in the regulation of male sexual differentiation and behavior in many vertebrates, including zebrafish. Their signaling is mediated by activation of the androgen receptor. A single androgen receptor (ar) gene was recently identified in zebrafish, which encodes a protein that binds androgens in vitro. However, the tissue‐specific expression pattern of this receptor in vivo has not been described. Using whole‐mount RNA in situ hybridization, we characterized expression of the ar gene in developing zebrafish and in the adult brain. In embryos, transcripts were found in the presumptive pronephros and in olfactory placodes. By 3–5 days postfertilization, ar transcripts were also detected in the pineal organ anlage and the retina. In the adult brain, ar was expressed in discrete regions of the telencephalon, in the preoptic area, and throughout the periventricular hypothalamus, regions previously implicated in the regulation of sexually dimorphic behaviors in mammals. Developmental Dynamics 237:2987–2995, 2008. © 2008 Wiley‐Liss, Inc.
Generation of oocyte‐specifically expressed cre transgenic zebrafish for female germline excision of loxp‐flanked transgene
Authors: Liu Xingjun , Li Zhen , Emelyanov Alexander , Parinov Serguei , Gong Zhiyuan 
Published: September 2008

AbstractIn this communication, we report the generation of a cre transgenic zebrafish line under an oocyte‐specific promoter, zp3. The transgenic line Tg(zp3:cre; krt8:rfp) also contains a co‐integrated rfp transgene under the skin epithelial promoter krt8 to allow selection of cre transgenic fish based on RFP fluorescence in the skin. We demonstrated in this transgenic line that cre mRNA was specifically expressed in growing oocytes like endogenous zp3 mRNA. When Tg(zp3:cre; krt8:rfp) was crossed with a loxP transgenic line, the floxed DNA was specifically eliminated from female, but not male, germline. Tg(zp3:cre; krt8:rfp) fish also have maternal cre mRNA in early embryos to cause Cre‐mediated recombination; this feature can be used to activate other loxP transgenic lines in early embryos. Furthermore, after crossing with another loxP transgenic line, Tg(EF:loxP‐mCherry‐loxP‐egfp), we confirmed that our cre line was capable of activating a loxP‐blocked EGFP reporter gene by both maternal and oocyte‐expressed Cre. Developmental Dynamics 237:2955–2962, 2008. © 2008 Wiley‐Liss, Inc.
Dynamic GATA6 expression in primitive endoderm formation and maturation in early mouse embryogenesis
Authors: Cai Kathy Q. , Capo‐Chichi Callinice D. , Rula Malgorzata E. , Yang Dong‐Hua , Xu Xiang‐Xi 
Published: September 2008

AbstractThe derivation of the primitive endoderm layer from the pluripotent cells of the inner cell mass is one of the earliest differentiation and morphogenic events in embryonic development. GATA4 and GATA6 are the key transcription factors in the formation of extraembryonic endoderms, but their specific contribution to the derivation of each endoderm lineage needs clarification. We further analyzed the dynamic expression and mutant phenotypes of GATA6 in early mouse embryos. GATA6 and GATA4 are both expressed in primitive endoderm cells initially. At embryonic day (E) 5.0, parietal endoderm cells continue to express both GATA4 and GATA6; however, visceral endoderm cells express GATA4 but exhibit a reduced expression of GATA6. By and after E5.5, visceral endoderm cells no longer express GATA6. We also found that GATA6 null embryos did not form a morphologically recognizable primitive endoderm layer, and subsequently failed to form visceral and parietal endoderms. Thus, the current study establishes that GATA6 is essential for the formation of primitive endoderm, at a much earlier stage then previously recognized, and expression of GATA6 discriminates parietal endoderm from visceral endoderm lineages. Developmental Dynamics 237:2820–2829, 2008. © 2008 Wiley‐Liss, Inc.
Essential role for fibrillin‐2 in zebrafish notochord and vascular morphogenesis
Authors: Gansner John M. , Madsen Erik C. , Mecham Robert P. , Gitlin Jonathan D. 
Published: September 2008

AbstractRecent studies demonstrate that lysyl oxidase cuproenzymes are critical for zebrafish notochord formation, but the molecular mechanisms of copper‐dependent notochord morphogenesis are incompletely understood. We, therefore, conducted a forward genetic screen for zebrafish mutants that exhibit notochord sensitivity to lysyl oxidase inhibition, yielding a mutant with defects in notochord and vascular morphogenesis, puff daddygw1 (pfdgw1). Meiotic mapping and cloning reveal that the pfdgw1 phenotype results from disruption of the gene encoding the extracellular matrix protein fibrillin‐2, and the spatiotemporal expression of fibrillin‐2 is consistent with the pfdgw1 phenotype. Furthermore, each aspect of the pfdgw1 phenotype is recapitulated by morpholino knockdown of fibrillin‐2. Taken together, the data reveal a genetic interaction between fibrillin‐2 and the lysyl oxidases in notochord formation and demonstrate the importance of fibrillin‐2 in specific early developmental processes in zebrafish. Developmental Dynamics 237:2844–2861, 2008. © 2008 Wiley‐Liss, Inc.
Maternal Tgif1 regulates nodal gene expression in Xenopus
Authors: Kerr Tyler C. , Cuykendall Tawny N. , Luettjohann Laura C. , Houston Douglas W. 
Published: September 2008

AbstractIn Xenopus, the maternal transcription factor VegT is necessary and sufficient to initiate the expression of nodal‐related genes, which are central to many aspects of early development. However, little is known about regulation of VegT activity. Using maternal loss‐of‐function experiments, we show that the maternal homeoprotein, Tgif1, antagonizes VegT and plays a central role in anteroposterior patterning by negatively regulating a subset of nodal‐related genes. Depletion of Tgif1 causes the anteriorization of embryos and the up‐regulation of nodal paralogues nr5 and nr6. Furthermore, Tgif1 inhibits activation of nr5 by VegT in a manner that requires a C‐terminal Sin3 corepressor‐interacting domain. Tgif1 has been implicated in the transcriptional corepression of transforming growth factor‐beta (TGFβ) and retinoid signaling. However, we show that Tgif1 does not inhibit these pathways in early development. These results identify an essential role for Tgif1 in the control of nodal expression and provide insight into Tgif1 function and mechanisms controlling VegT activity. Developmental Dynamics 237:2862–2873, 2008. © 2008 Wiley‐Liss, Inc.
Toward understanding the morphogenesis of siliceous spicules in freshwater sponge: Differential mRNA expression of spicule‐type‐specific silicatein genes in Ephydatia fluviatilis
Authors: Mohri Kurato , Nakatsukasa Mikiko , Masuda Yoshiki , Agata Kiyokazu , Funayama Noriko 
Published: September 2008

AbstractSiliceous spicules of sponges are morphologically diverse and provide good models for understanding the morphogenesis of biomineralized products. The silica deposition enzyme silicatein is a component of siliceous spicules of sponges and is thought to be the key molecule determining the morphology of spicules. Here, we focused on the silicateins of the freshwater sponge Ephydatia fluviatilis, which has two types of morphologically and functionally different spicules, called megascleres and gemmoscleres. We isolated six isoforms of silicateins and examined their mRNA expression in the cells producing megascleres and gemmoscleres. The spicule‐type‐specific mRNA expression of these isoforms and differential expression during spicule development suggest that the characteristic morphology of spicules is due to the specific properties and combinatory functions of silicatein isoforms. Developmental Dynamics 237:3024–3039, 2008. © 2008 Wiley‐Liss, Inc.
Gli3‐deficient mice exhibit cleft palate associated with abnormal tongue development
Authors: Huang Xi , Goudy Steven L. , Ketova Tatiana , Litingtung Ying , Chiang Chin 
Published: September 2008

AbstractPalatogenesis depends on appropriate growth, elevation, and fusion of the palatal shelves and aberration in these processes can lead to palatal clefting. We observed a high incidence of palate clefting in mice deficient in Gli3, known for its role as a repressor in the absence of Shh signaling. In contrast with several current mouse models of cleft palate, Meckel's cartilage extension, cranial neural crest migration, palatal shelf proliferation, apoptosis, and key signaling components mediated by Shh, Bmp, Fgf, and Tgfβ, appeared unaffected in Gli3−/− mice. Palatal clefting in Gli3−/− mice was consistently associated with tongue abnormalities such as failure to flatten and improper positioning, implicating a critical role of Gli3 and normal tongue morphogenesis for timely palatal shelf elevation and joining. Furthermore, Gli3−/− palatal shelves grown in roller cultures without tongue can fuse suggesting that the abnormal tongue is likely an impediment for palatal shelf joining in Gli3−/− mutants. Developmental Dynamics 237:3079–3087, 2008. © 2008 Wiley‐Liss, Inc.
Retinoic acid down‐regulates Tbx1 expression and induces abnormal differentiation of tongue muscles in fetal mice
Authors: Okano Junko , Sakai Yasuo , Shiota Kohei 
Published: September 2008

AbstractExcess retinoic acid (RA) during pregnancy can cause various developmental anomalies in both humans and rodents. We investigated the mechanisms underlying the aberrant differentiation of tongue muscles in fetal mice exposed to exogenous RA in utero. RA‐degrading enzymes (Cyp26a1 and Cyp26b1) were expressed at early stages of normal tongue development, but exogenous RA perturbed their expression in the fetal tongue. RA is normally distributed in the developing tongue muscles but its localization was disrupted by exogenous RA. After RA treatment, myogenic determination factors were reduced and the differentiation was significantly suppressed in tongue muscles. Tbx1, a candidate gene of DiGeorge syndrome, was down‐regulated in the fetal tongue in response to excess RA. Moreover, Tbx1 as well as myogenic determination factors were not observed in tongue muscle primordia of Cyp26b1−/− fetuses. Our study suggests that RA signaling may play an essential role in tongue muscle differentiation via the regulation of Tbx1. Developmental Dynamics 237:3059–3070, 2008. © 2008 Wiley‐Liss, Inc.
Properties of branchiomeric and somite‐derived muscle development in Tbx1 mutant embryos
Authors: Grifone Raphälle , Jarry Thérèse , Dandonneau Mathieu , Grenier Julien , Duprez Delphine , Kelly Robert G. 
Published: September 2008

AbstractVertebrate craniofacial and trunk myogenesis are regulated by distinct genetic programs. Tbx1, homologue of the del22q11.2 syndrome candidate gene TBX1, controls branchiomeric craniofacial muscle development. Here, we demonstrate using immunohistochemistry that myogenic regulatory factors are activated in Tbx1‐positive cells within pharyngeal mesoderm. These cells are also Islet1 and Capsulin‐positive and in the absence of Tbx1 persist in the core of the first arch. Sporadic hypoplastic mandibular muscles in Tbx1−/− embryos contain Pax7‐positive myocytes with indistinguishable differentiation properties from wild‐type muscles and have normal tendon attachments and fiber‐type patterning. In contrast to TBX1 haploinsufficient del22q11.2 syndrome patients, no alteration in fiber‐type distribution was detected in Tbx1+/− adult masseter and pharyngeal constrictor muscles. Furthermore, Tbx1‐expressing limb muscles display normal patterning, differentiation, fiber‐type growth, fiber‐type distribution and fetal maturation in the absence of Tbx1. The critical requirement for Tbx1 during muscle development is thus in the robust onset of myogenic specification in pharyngeal mesoderm. Developmental Dynamics 237:3071–3078, 2008. © 2008 Wiley‐Liss, Inc.
Temporal and spatial expression of collagens during murine atrioventricular heart valve development and maintenance
Authors: Peacock Jacqueline D. , Lu Yinhui , Koch Manuel , Kadler Karl E. , Lincoln Joy 
Published: September 2008

AbstractHeart valve function is achieved by organization of matrix components including collagens, yet the distribution of collagens in valvular structures is not well defined. Therefore, we examined the temporal and spatial expression of select fibril‐, network‐, beaded filament‐forming, and FACIT collagens in endocardial cushions, remodeling, maturing, and adult murine atrioventricular heart valves. Of the genes examined, col1a1, col2a1, and col3a1 transcripts are most highly expressed in endocardial cushions. Expression of col1a1, col1a2, col2a1, and col3a1 remain high, along with col12a1 in remodeling valves. Maturing neonate valves predominantly express col1a1, col1a2, col3a1, col5a2, col11a1, and col12a1 within defined proximal and distal regions. In adult valves, collagen protein distribution is highly compartmentalized, with ColI and ColXII observed on the ventricular surface and ColIII and ColVa1 detected throughout the leaflets. Together, these expression data identify patterning of collagen types in developing and maintained heart valves, which likely relate to valve structure and function. Developmental Dynamics 237:3051–3058, 2008. © 2008 Wiley‐Liss, Inc.
The developmental sequence of gene expression within the rod photoreceptor lineage in embryonic zebrafish
Authors: Nelson Steve M. , Frey Ruth A. , Wardwell Sheri L. , Stenkamp Deborah L. 
Published: September 2008

AbstractIn postembryonic zebrafish, rod photoreceptors are continuously generated from progenitors in the inner nuclear layer, which are derived from radial Müller glia that express the transcription factor pax6. We used BrdU incorporation, in combination with in situ hybridization for cell‐specific transcription factors, to establish the patterns of gene expression during rod lineage maturation in the embryonic zebrafish. Downregulation of pax6 expression was accompanied by sporadic upregulation of expression of the transcription factors NeuroD/nrd, rx1, crx, and Nr2e3/pnr. As cells of the rod lineage entered the outer nuclear layer, they became homogeneous, coordinately expressing NeuroD, rx1, crx, and Nr2e3. Postmitotic, maturing rods also expressed nrl, rod opsin, and rod transducin/gnat1. The presence of rx1 within the rod lineage and in maturing rods indicates that rx1 is not cone‐specific, as previously reported, and suggests a high degree of molecular similarity between rod and cone progenitor populations in the zebrafish. Developmental Dynamics 237:2903–1917, 2008. © 2008 Wiley‐Liss, Inc.
Identification and characterization of subpopulations of Pax3 and Pax7 expressing cells in developing chick somites and limb buds
Authors: Galli Lisa M. , Knight Sara R. , Barnes Tiffany L. , Doak Allison K. , Kadzik Rachel S. , Burrus Laura W. 
Published: September 2008

AbstractImmunostaining of a transverse section of a HH st 18 chick embryo with Pax3 (green), Pax7 (blue), and MyoD (red) is shown in the upper left panel. All other panels display the same markers in different colors. The image was collected by confocal microscopy. See Galli et al., Developmental Dynamics 237:1862‐1874. © 2008 Wiley‐Liss, Inc.
Lack of galectin‐3 alters the balance of innate immune cytokines and confers resistance to Rhodococcus equi infection
Authors: Ferraz Luciana C. , Bernardes Emerson S. , Oliveira Aline F. , Ruas Luciana P. , Fermino Marise L. , Soares Sandro G. , Loyola Adriano M. , Oliver Constance , Jamur Maria C. , Hsu Daniel K. , Liu Fu‐Tong , Chammas Roger , Roque‐Barreira Maria‐Cristina 
Published: September 2008

AbstractGalectin‐3 is a β‐galactoside‐binding lectin implicated in the fine‐tuning of innate immunity. Rhodococcus equi, a facultative intracellular bacterium of macrophages, causes severe granulomatous bronchopneumonia in young horses and immunocompromised humans. The aim of this study is to investigate the role of galectin‐3 in the innate resistance mechanism against R. equi infection. The bacterial challenge of galectin‐3‐deficient mice (gal3−/−) and their wild‐type counterpart (gal3+/+) revealed that the LD50 for the gal3−/− mice was about seven times higher than that for the gal3+/+ mice. When challenged with a sublethal dose, gal3−/− mice showed lower bacteria counts and higher production of IL‐12 and IFN‐γ production, besides exhibiting a delayed although increased inflammatory reaction. Gal3−/− macrophages exhibited a decreased frequency of bacterial replication and survival, and higher transcript levels of IL‐1β, IL‐6, IL‐10, TLR2 and MyD88. R. equi‐infected gal3+/+ macrophages showed decreased expression of TLR2, whereas R. equi‐infected gal3−/− macrophages showed enhanced expression of this receptor. Furthermore, galectin‐3 deficiency in macrophages may be responsible for the higher IL‐1β serum levels detected in infected gal3−/− mice. Therefore galectin‐3 may exert a regulatory role in innate immunity by diminishing IL‐1β production and thus affecting resistance to R. equi infection.
IFN‐β regulates CD73 and adenosine expression at the blood–brain barrier
Authors: Niemelä Jussi , Ifergan Igal , Yegutkin Gennady G. , Jalkanen Sirpa , Prat Alexander , Airas Laura 
Published: September 2008

AbstractIFN‐β treatment reduces the relapse rate in MS but its mechanism of action remains incompletely understood. Our aim was to clarify the beneficial effect of IFN‐β in the treatment of MS. We assessed the influence of IFN‐β treatment on (i) CD73 expression on the surface of primary cultures of human blood–brain barrier endothelial cells (BBB‐EC) and human astrocytes using immunofluorescence staining and flow cytometry, (ii) transmigration of CD4+ T lymphocytes using an in vitro model of BBB and (iii) CD73 enzyme activity, i.e. ecto‐5′‐nucleotidase activity in the serum of MS patients using a radiochemical assay. IFN‐β increases the expression of ecto‐5′‐nucleotidase both on BBB‐EC and astrocytes. As a consequence, lymphocyte transmigration through BBB‐EC is reduced. Importantly, this reduction can be reversed using α,β‐methyleneadenosine‐5′‐diphosphate, a specific inhibitor of ecto‐5′‐nucleotidase. CD73 is strongly expressed in microvasculature in samples of postmortem MS brain and, moreover, in the majority of MS patients there was a clear upregulation both in the soluble serum ecto‐5′‐nucleotidase activity and skin microvascular CD73 expression after IFN‐β treatment. Upregulation of ecto‐5′‐nucleotidase and a subsequent increase in adenosine production might contribute to the beneficial effects of IFN‐β on MS via enhancing the endothelial barrier function.
Slow‐Proton Dynamics within a Zirconium‐Containing Sandwich‐Like Complex Based on the Trivacant Anion α‐[SiW9O34]10– – Synthesis, Structure and NMR Spectroscopy
Authors: Leclerc‐Laronze Nathalie , Marrot Jérôme , Haouas Mohamed , Taulelle Francis , Cadot Emmanuel 
Published: September 2008

AbstractReaction of ZrOCl2 with the potassium tungstosilicate A‐α‐[SiW9O34]10– in water at pH = 4 leads to the formation of the sandwich‐type complex [Zr3O(OH)2(SiW9O34)2]12– (H2‐1) which has been structurally characterised by single‐crystal X‐ray diffraction. It consists of a [Zr3O(OH)2] triangular central cluster closely embedded between two A‐α‐[SiW9O34]10– subunits. Inspection of the geometric parameters within the {Zr3O3} core unambiguously reveals the presence of two attached protons giving two hydroxo Zr–OH–Zr bridges and a single oxo Zr–O–Zr junction. The anions Hx‐1 with x = 3, 2 or 1 were obtained in solution at pH = 2, 4 and 7.5, respectively, and were subsequently characterised by 183W and 29Si NMR spectroscopy in aqueous solution. 183W NMR spectra appear strongly dependent upon the protonation state of the trizirconium central core, {HxZr3O3}. 183W NMR spectroscopy of H2‐1 gives a two‐line spectrum, consistent only with the hopping of the two H+ ions over the three bridging Zr–O–Zr oxygen atoms. Interestingly, the resonance attributed to the six tungsten atoms of the belt connected to the zirconium atoms through W–O–Zr junctions exhibits substantial line‐broadening (Δν1/2 = 21 Hz) interpreted as a slow dynamic process involving the H+ ions. Such behaviour contrasts with the fast H+ mobility generally observed in other POM systems and this will be discussed in relation to the peculiar environment of the {Zr3O3} core which hinders structural relaxation consequent with the H+ hopping. Both 183W resonances of the H3‐1 anion remain sharp as usual (Δν1/2 = 1.6 Hz) consistent with the presence of the triprotonated species [Zr3(OH)3(SiW9O34)2]11– whereas for the monoprotanated anion (H‐1), the resonance of the belt becomes broad enough to be indistinguishable. Infrared spectroscopy, elemental analysis, pH titration and polarographic measurements of Hx‐1 were also carried out.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Gas‐Phase Chemistry of Vanadium Oxide Cluster Cations VmOn+ (m = 1–4; n = 1–10) with Water and Molecular Oxygen
Authors: Feyel Sandra , Schröder Detlef , Schwarz Helmut 
Published: September 2008

AbstractBare vanadium oxide cluster cations VmOn+ (m = 1–4; n =1–10) generated by electrospray ionization are investigated with respect to their reactivity toward water and molecular oxygen by using mass spectrometric techniques. Besides ion hydration, the ion/molecule reactions of VmOn+ with oxygen‐labeled water (H218O) also lead to 16O/18O exchange reactions of the vanadium oxide clusters cations. Although the probability of degenerate 16O/18O exchange between VmOn+ and water is fairly high for the cluster cations with a medium valence state of vanadium, oxygen‐atom exchange reactions between VmOn+ and 18O2 can only be accomplished by VO+, V3O6+, and V4O8+. Particularly interesting is the fact that not only oxygen atoms from vanadyl units are exchanged in the cluster cations, but bridging oxygen atoms are also most likely involved in the processes. Other reaction channels for the interaction of VmOn+ cluster cations with molecular oxygen are reported as well, such as oxidative degradation of the low‐valent cluster cations upon collision with O2 and formation of association complexes for the high‐valent cluster cations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)