Making mesoderm-upstream and downstream of Xbra 219 Making mesoderm–upstream and downstream of Xbra
نویسنده
چکیده
The mesoderm of the amphibian embryo is formed through an inductive interaction in which cells of the vegetal hemisphere of the embryo act on overlying equatorial cells. My laboratory is studying the Brachyury gene, which plays a key role in this interaction, being both necessary and sufficient for normal mesoderm formation. In this article I describe our attempts to understand how Xenopus Brachyury (Xbra) is activated in the right cells at the right time, and then to understand how Xbra exerts its effects.
منابع مشابه
Mesoderm formation in response to Brachyury requires FGF signalling
BACKGROUND The Brachyury (T) gene is required for the formation of posterior mesoderm and for axial development in both mouse and zebrafish embryos. In these species, and in Xenopus, the gene is expressed transiently throughout the presumptive mesoderm, and transcripts then persiste in notochord and posterior tissues. In Xenopus embryos, expression of the Xenopus homologue of Brachyury, Xbra, c...
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Brachyury, a member of the T-box gene family, is required for posterior mesoderm and notochord differentiation in vertebrate development, and mis-expression of Xenopus Brachyury causes ectopic mesoderm formation. Brachyury is a transcription activator, and its ability to activate transcription is essential for its biological function, but Brachyury target genes have proved difficult to identify...
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Xenopus Brachyury (Xbra) plays a key role in mesoderm formation during early development. One factor thought to be involved in the regulation of Xbra is XSIP1, a zinc finger/homeodomain-like DNA-binding protein that belongs to the deltaEF1 family of transcriptional repressors. We show here that Xbra and XSIP1 are co-expressed at the onset of gastrulation, but that expression subsequently refine...
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Cellular competence is defined as a cell's ability to respond to signaling cues as a function of time. In Xenopus laevis, cellular responsiveness to fibroblast growth factor (FGF) changes during development. At blastula stages, FGF induces mesoderm, but at gastrula stages FGF regulates neuroectoderm formation. A Xenopus Oct3/4 homologue gene, XLPOU91, regulates mesoderm to neuroectoderm transit...
متن کاملXbra3 induces mesoderm and neural tissue in Xenopus laevis.
Homologues of the murine Brachyury gene have been shown to be involved in mesoderm formation in several vertebrate species. In frogs, the Xenopus Brachyury homologue, Xbra, is required for normal formation of posterior mesoderm. We report the characterisation of a second Brachyury homologue from Xenopus, Xbra3, which has levels of identity with mouse Brachyury similar to those of Xbra. Xbra3 en...
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