.... In contrast, adult LCs were absent from postnatal testes. In addition, adult mutant males displayed persistence of Müllerian duct derivatives, decreased anogenital distance and reduced penis length, which could be explained by the loss of AMH and testosterone synthesis due to SC failure. Competing...

...Hussein A. Saud; Paul A. O'Neill; Yosuke Ono; Bas Verbruggen; Ronny Van Aerle; Jaebum Kim; Jae-Seong Lee; Brian C. Ring; Tetsuhiro Kudoh ABSTRACT Using the self-fertilizing mangrove killifish, we characterized two mutants, shorttail ( stl ) and balltail ( btl ). These mutants showed abnormalities...

... nanog (maternal and zygotic null) mutant zebrafish embryos . Without functional Nanog, epiboly is severely affected, embryo axes do not form and massive cell death starts at the end of gastrulation. We show that three independent defects in MZ nanog mutants contribute to epiboly failure: yolk...

...Nikolaus Obholzer; Ian A. Swinburne; Evan Schwab; Alex V. Nechiporuk; Teresa Nicolson; Sean G. Megason Forward genetic screens in zebrafish have identified >9000 mutants, many of which are potential disease models. Most mutants remain molecularly uncharacterized because of the high cost, time...

... or western blot. The mutant esophagus morphologically resembles the trachea,with ectopic expression of Nkx2.1, a columnar, ciliated epithelium, and very few p63 + basal cells. By contrast, the abnormal foregut of Nkx2.1 -null embryos expresses elevated Sox2 and p63, suggesting reciprocal regulation of Sox2...

... phenotypes. Thirteen recessive mutations in 12 genes were discovered. In one mutant, ddl , the majority of RGCs fail to differentiate. Three of the mutations, vrt , late and tard , delay the orderly ingrowth of retinal axons into the tectum. Two alleles of drg disrupt the layer-specific targeting of retinal...

... studied as a paradigm of tissue pattern formation in plants. To elucidate the molecular mechanism controlling the vein patterning process,we previously isolated Arabidopsis mutants van1 to van7 , which show a discontinuous vein pattern. Here we report the phenotypic analysis of the van3 mutant in relation...

... and matrix metalloproteinases suggests that matrix remodeling within the hypertrophic zones in Ctgf mutants is defective. The mutant phenotype also revealed a role for Ctgf in growth plate angiogenesis. Hypertrophic zones of Ctgf mutant growth plates are expanded, and endochondral ossification is impaired...

... in these two screens overlap. However it is likely that there will be genes that are required for border cell migration that would not rescue a slbo mutant when over- expressed. One concern about genes identified based on the phenotype produced in mosaic clones is that the screen might identify...

...Jarema Malicki; Wolfgang Driever ABSTRACT Mutations of the oko meduzy (ome) locus cause drastic neuronal patterning defect in the zebrafish retina. The precise, stratified appearance of the wild-type retina is absent in the mutants. Despite the lack of lamination, at least seven retinal cell types...

... Mutations giving rise to anatomical defects in the inner ear have been isolated in a large scale screen for mutations causing visible abnormalities in the zebrafish embryo ( Haffter, P., Granato, M., Brand, M. et al. (1996) Development 123, 1-36). 58 mutants have been classified as having a primary ear...

..., a tissue whose proliferation rate is abnormal in the ct mutant, and RAR-γ transcripts are deficient in the tail bud and posterior neuropore region. The degree of deficiency of RAR-γ transcripts is correlated with the severity of delay of posterior neuropore closure. As early as 2 hours following RA...

... effect on the pattern of neural crest-derived pigment cells, and in homozygous mutant embryos by visible defects in craniofacial structures. Since both pigment cells and craniofacial structures are derived from the neural crest, we have examined the differentiation of other crest cell-derived structures...

...Ko Hatanaka; Masukichi Okada ABSTRACT Three X-linked mutations of Drosophila melanogaster, gs ( l ) N26, gs ( l ) N441 and paralog , had a common maternal-effect phenotype. Mutant embryos show reduced egg contraction that normally occurs at an early cleavage stage in wild-type embryos. In addition...

... dysmyelination mutant myelin glia jimpy proteolipid protein gene oligodendrocyte canine development. Myelination is a developmentally controlled process whereby neuronal axons are enwrapped by a multilayer membrane sheath. In the central nervous system (CNS), this function is carried out...

...Pat Simpson; Cathie Carteret A study of shaggy mutant clones on the notum reveals that a greater number of cells are diverted into the bristle pathway of differentiation and fewer cells remain to produce the epidermis, shaggy clones differentiate supernumerary microchaetae and macrochaetae...

...Andrew J. Copp; Frances A. Brook; Heather J. Roberts ABSTRACT The mouse mutant curly tail (ct) provides a model system for studies of neurulation mechanisms. 60 % of ct/ct embryos develop spinal neural tube defects (NTD) as a result of delayed neurulation at the posterior neuropore whereas...

..., there is a poleward expansion of the remaining pattern. Using anti-horseradish peroxidase staining, we show that the formation of the embryonic brain requires tll . A phenotypic and genetic study of other pattern mutants places the tll gene within the hierarchy of maternal and zygotic genes required for the formation...

...) expression as markers for the body plan, we have studied the phenotype of pair-rule mutants prior to cell death. All these mutants alter the expression of en and Ubx; then-molecular phenotypes suggest a pathway whereby pair-rule gene functions construct metameric units. * Present address: Department...

... were mapped to defined positions in the eye-antennal imaginal disc by transplanting abnormal regions of discs isolated from tuh-3 mutants into host mwh;e 4 larvae. These metamorphosed implants were removed and differentiated structures were identified. Of 211 successfully recovered implants, 157 gave...