sox9a

..to isolate a mutation deleting sox9b function, and investigated its phenotype and genetic interactions with a sox9a null mutation...

..As SEC23A lesions cause the cranio-lenticulo-sutural dysplasia syndrome, crusher provides the first vertebrate model system that links the biology of endoplasmic reticulum to Golgi trafficking with a clinically relevant dysmorphology...

..its expression pattern in embryos, larvae, juveniles, and adults, and compared it to the expression patterns of sox9a, sox9b and cyp19a1a...

..The role of FTZ-F1 and other candidates for zebrafish sex determination and differentiation is in focus of this review...

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..Together, these results indicate an essential role for barx1 at early stages of chondrogenesis within the developing zebrafish viscerocranium...

..Up-regulation of sox9a, sox9b, and runx2b in mutants suggested a molecular mechanism consistent with a role for proteoglycans in ..

..Here we study chameleon mutants, lacking a functional disp1(con/disp1)...

..Collectively, our results indicate that Edn1 from the pharyngeal ectoderm signals through Ednra proteins to direct early dorsoventral patterning of the skeletogenic neural crest...

..Combined loss of both factors eliminates all indications of otic specification. We suggest that the Foxi1-Pax8 pathway provides an early 'jumpstart' of otic specification that is maintained by the Dlx3b-Pax2a pathway...

..Zebrafish embryos homozygous for jellyfish (jef) mutations show craniofacial defects and lack cartilage elements of the neurocranium, pharyngeal arches, ..

..In hammerhead mutants particularly the mesodermally derived cartilages are reduced, whereas jellyfish mutant larvae are characterized by a severe reduction of all cartilaginous elements, leaving only two pieces in ..

..Removal of dlx3b, dlx4b and sox9a genes together also blocks ear development, although a few residual cells form an otic epithelium...

..Most expression domains appear to have been partitioned between Sox9a and Sox9b before the divergence of stickleback and zebrafish lineages, but some ancestral expression domains were ..

..analysis revealed that both our isolated Sox9 and the already reportedly cloned medaka Sox9 belongs zebrafish Sox9a branch. Therefore, we named our gene Sox9a2...

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..phase the craniofacial primordia in pharyngeal arches two to seven fail to express their typical set of genes (sox9a, wnt5a, dlx2, hoxa2/b2)...

..Stein und bein (sub) has reduced dorsal and pelvic fins, whereas finless (fls) and wanda (wan) mutants affect all adult fins. Finally, mutations in four genes causing defects in embryonic skin formation will be briefly reported...

..Together, these results indicate an essential role for prdm1a in the development of the zebrafish craniofacial skeleton...

..cyp26b1 mutants may serve as a model to study the etiology of human vertebral disorders such as Klippel-Feil anomaly...

..Moreover, the defects observed in cartilage formation resemble those observed in human chondrodysplasia such as the Stickler/Marshall syndrome. Zebrafish represent a novel reliable vertebrate model for collagen XI collagenopathies...

..In contrast, at 2 dpf, a severe reduction in the expression of sox9a, colIIaI, and runx2b, which play roles in chondrocytic proliferation and differentiation, was observed...

..Staining with digoxigenin-labeled dlx2a, sox9a, runx2b and col2a1 riboprobes showed that nf-yb-morphants displayed reduced amounts of cranial neural crest cells ..

..of neural crest cell diversification in double mutants is accompanied by the absence of neural crest sox10 and sox9a/b gene expression, and that forced expression of sox10 and sox9a/b differentially rescues neural crest sublineage ..

..Our study presents the first developmental perspective on Sec24D function and establishes Sec24D as a strong candidate for cartilage maintenance diseases and craniofacial birth defects...

..animals the expression of the ovary specific gene cyp19a1a fails to be maintained whereas the testis genes sox9a and amh remain expressed...

..Using a combination of mutant and morphant data, we show that the three sox genes belonging to group E (sox9a, sox9b and sox10) provide a link between otic induction pathways and subsequent otic patterning: they act ..

..Danio rerio), we performed morpholino knockdown to block translation of the ff1a gene and the upstream located sox9a gene during embryogenesis...

..abnormality as a result of a failure of CNC to differentiate into and express cartilage-specific markers, such as sox9a and col2a1. Administration of faf1 mRNA rescues this phenotype...

..These findings highlight the potential of the zebrafish system in studying lysosomal disease pathogenesis...

..These observations suggest that irxl1 may regulate factors involved in brain and pharyngeal arch development...

..In contrast to PARP1 and PARP2, the functions of PARP3 are undefined. Here, we reveal critical functions for PARP3 during vertebrate development...

..Taken together, these data demonstrate a novel role for loxl3b in the maturation of craniofacial cartilage and can provide new insight into the specific genetic factors important in the pathogenesis of craniofacial birth defects...

..Finally, we show that like endogenous col2a1a, craniofacial expression of these reporter constructs depends on Sox9a transcription factor activity...

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..Collectively, our work indicates that the expression and function of hand2 and Dlx genes specify major patterning domains along the dorsoventral axis of zebrafish pharyngeal arches...

..These findings provide novel insights into the origin of cells in epimorphic appendage regeneration in zebrafish and suggest conservation of regeneration mechanisms between fish and amphibians...

..Therefore, proper cranial neural crest formation and survival, and ultimately craniofacial chondrogenesis and osteogenesis, are dependent on tight regulation of Tgfbeta3 protein levels in zebrafish...

..This work illustrates that radar is regulated in the pharyngeal arches by a distant conserved element and suggests radar has similar functions in skeletal development in fish and mammals...

..These findings might help to increase our understanding of skeletal and obesity-related diseases and aid in the development of stem cell-based regenerative therapies...

..Understanding the requirements for Hh-signaling in organisms can be gained by assessing Gli activity in a spatial and temporal fashion...

..we used microarray expression profiling to compare wild-type embryos to mutant embryos lacking activity for both sox9a and sox9b, the zebrafish co-orthologs of Sox9...

..In contrast, pic(-/-) chondrocytes always act autonomously and can disrupt the morphology of neighbouring wild-type cells. These findings lead to the development of a new model to explain the aetiology of HME...

..The current study investigates the expression of all six genes in the same individual fish with extensive sampling dates during sex determination and -differentiation...

..The differences in pI values, the instability index, and DNA contact regions between sequence and non-sequence specific HMG domains are associated with their functional modes...

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..However, many essential genes required for craniofacial development remain to be identified...

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..This review addresses the most recent advances in our understanding of how the ear forms and discusses the molecules in hair cells that are essential for sensing sound and movement in the zebrafish...

..This indicates that under replication-compromised conditions, the p53 branch of the S-phase checkpoint is responsible for eliminating stalled cells that, given more time, would have otherwise finished their normal developmental program...

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..analysis, phylogenetic data, linkage mapping as well as expression pattern all together suggest that the medaka Sox9a and Sox9b are co-orthologs...

..characteristic of Sertoli cells such as phagocytic activity and transcription both of their specific genes, sox9a and Wilms' tumor suppressor WT1, and of the vas gene of germ cells were analyzed in the lines...

..In addition, two transcription factors essential for chondrogenesis, sox9a and runx2b, fail to express within the mesenchymal condensations of the branchial arches...

..and zebrafish: bmp2b, bmp4, chordin, and gdf5 in interradial mesenchyme and ZS; bapx1, col2a1, noggin3, and sox9a in chondrocytes. Surprisingly, wnt9a is not expressed in the developing median fins, though wnt9b is detected...

..Knockdown of dlx2a affects migrating neural crest cells as evidenced by reduced expression of crestin, and sox9a transcripts, in addition to increased levels of apoptosis...

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..A comparison of the phenotypes of Sparc knockdown and known zebrafish mutants with similar defects places Sparc downstream of sox9 in the genetic network that regulates development of the pharyngeal skeleton and inner ear of vertebrates...

..We previously suggested that Foxi1 and Dlx3b may provide competence to form the ear because loss of both foxi1 and dlx3b results in ablation of all otic tissue even in the presence of a fully functional Fgf signaling pathway...

..Furthermore, it will help to identify novel genes and regulatory pathways of bone homeostasis and skeletal disorders also in higher vertebrates, including disorders caused by altered gravity...

..Rather, it represents a less well-conserved layer of sequence organization within these sequences...

..We conclude that Brpf1, coordinated by its particular set of domains, acts by multiple mechanisms to mediate Moz-dependent histone acetylation and to mark Hox genes for maintained expression throughout vertebrate development...

..These data show that pax8 is initially required for normal otic induction, and subsequently pax8, pax2a and pax2b act redundantly to maintain otic fate...

..Further analysis of mosm188 mutants and foxd3 morphants revealed that NC cells are initially formed, suggesting that foxd3 function is required to maintain the pool of NC progenitors...

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..In zebrafish, there are two Sox9 orthologs, Sox9a and Sox9b, which together perform the functions of the single-copy tetrapod Sox9...

..runx2a/b and their target col10a1 were downregulated following BMP signaling inhibition. Unexpectedly, the sox9a/b transcription factors responsible for chondrocyte differentiation were detected in the non-cartilaginous fin ..

..Together, our analyses reveal a regulatory role of Mot/Med12 in vertebrate neuronal development...

..Failed mitosis in the absence of Ubc9 is not necessarily coupled with cell death. Rather, cells can continue to replicate their DNA, grow to a larger size, and finish their normal developmental program...

..Overall, for the first time in vivo, our results reveal a mechanism of FGF in the control of neural cell diversity...

..The major goals of this project are to use zebrafish and mice as model organisms to determine mechanisms by which facial tissues are formed and to uncover avenues for rescue and repair of a specific congenital craniofacial birth defect. ..

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..Additionally, two genes I propose to analyze, pitx2 and ephrin-B1, are known to be human craniofacial disease genes. Therefore, my analyses of these genes will provide direct insight into the cause of human disease. ..

..These processes are likely to persist in the adult skeleton, and to be altered in human malformations and diseases of the skeleton. ..

..The data from these experiments will help to increase our understanding of the biology of deafness genes and may lead to potential therapies for deafness patients. ..

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..Aim 3 focuses on a particular tissue interaction that requires RA, between the mesoderm and developing neural tube, by using cell transplantation in RALDH2 mutants to get to the biochemical basis for neural patterning. ..

..Last, a forward genetic screen will be used to discover new mutations that affect the development of neurocranial cartilages. ..

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..These processes are likely to persist in the adult skeleton, and to be altered in human malformations and diseases of the skeleton. ..