MOLECULAR REGULATION OF EARLY XENOPUS DEVELOPMENT

非洲爪蟾早期发育的分子调控

• 批准号: 2200335
• 负责人: David Kimelman
• 金额: $ 22.21万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-08-01 至 1999-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2200335
• 关键词: Xenopus; alternatives to animals in research; biological signal transduction; cadherins; cell cell interaction; density gradient ultracentrifugation; developmental genetics; early embryonic stage; fibroblast growth factor; gap junctions; genetic regulation; genetic transcription; growth factor receptors; histogenesis; immunoprecipitation; mesoderm; messenger RNA; nonmammalian vertebrate embryology; polymerase chain reaction; protein kinase; protein structure function; transcription factor

Development of the vertebrate embryo depends on intercellular signaling to specify the fate of cells comprising the embryonic body. Although many of the intercellular inducing factors involved in these signaling events have now been identified (e.g. FCF, Vg1, Xwnt, noggin), it is not known how intracellular signals triggered by these factors mediate cell fate. Toward this end, we have isolated a SER/THR kinase, Xgsk-3, from the amphibian, Xenopus laevis. Inhibition of Xgsk-3 activity on the ventral side of the embryo with a dominant-negative mutant of Xgsk-3, leads to embryos with completely twinned axes, including secondary heads. This result indicates that Xgsk-3 actively represses axis formation in the early embryo, and that axal development requires the repression of Xgsk-3 activity within the future Spemann organizer, establishing Xgsk-3 as a major intracellular regulator of early axis formation in the Xenopus embryo. In addition, genetic evidence from DrosophiLa, together with localization of the Xgsk-3 gene in Xenopus, suggests that it may also be an important regulator of the neuroectoderm. Three major areas will be pursued: 1. The regulation of Xgsk-3 in early axial patterning will be investigated, by developing biochemical assays for Xgsk-3 function. These experiments will determine which inducing factors have the ability to regulate Xgsk-3, and will ultimately elucidate the mechanism for Xgsk-3 inhibition during early development 2. The role of Xgsk-3 in later axial development and neural development will be determined, using the dominant-negative mutant of Xgsk-3 to block its function during different stages of embryogenesis. 3. A search for the proteins that regulate Xgsk-3 and that are regulated by Xgsk-3 during different developmental stages will be conducted in order to elucidate the intracellular signaling pathway that regulates axis development in the Xenopus embryo. The ultimate goal of this proposal is to provide a dear mechanistic understanding of the intracellular signaling processes that underlie vertebrate embryonic development. Since birth defects are due to a failure in the normal processes of embryogenesis, these studies will delineate the processes that can be perturbed by dysmorphogenic agents and genetic abnormalities.

脊椎动物胚胎的发展取决于细胞间信号传导 指定包含胚胎体的细胞的命运。 虽然 这些信号中涉及的许多细胞间诱导因子 现在已经确定了事件（例如FCF，VG1，XWNT，Noggin），不是 知道这些因素触发的细胞内信号如何介导细胞 命运。 为此，我们从 两栖动物，Xenopus laevis。 抑制XGSK-3活性对 胚胎的腹侧，具有XGSK-3的显性阴性突变体， 导致具有完全孪晶轴的胚胎，包括次级头部。 该结果表明XGSK-3主动抑制了轴形成 早期的胚胎和轴向发育需要抑制 XGSK-3的未来Spemann组织者中的活动，建立XGSK-3 作为爪蟾早期轴形成的主要细胞内调节剂 胚胎。 此外，果蝇的遗传证据以及 XGSK-3基因在爪蟾中的定位表明它也可能是 神经外胚层的重要调节剂。 将三个主要领域 追踪：1。在早期轴向图案中对XGSK-3的调节将是 通过开发用于XGSK-3功能的生化测定法进行了研究。这些 实验将确定哪些诱导因素具有能力 调节XGSK-3，并最终阐明XGSK-3的机制 早期开发期间的抑制作用2。XGSK-3在后来的轴向中的作用 开发和神经发展将使用 XGSK-3的主要阴性突变体在不同的情况下阻止其功能 胚胎发生的阶段。 3。搜索调节的蛋白质 XGSK-3和在不同发育期间由XGSK-3调节的 将进行阶段以阐明细胞内 信号通路调节爪蟾胚胎中的轴发育。 该提议的最终目标是提供一个亲爱的机械 了解基于的细胞内信号传导过程 脊椎动物胚胎发育。 由于出生缺陷是由于 在胚胎发生的正常过程中的失败，这些研究将 描述可能会受到畸形剂扰动的过程 和遗传异常。