REGULATION OF ANTEROPOSTERIOR PATTERNING IN EARLY FROG DEVELOPMENT

POU转录因子已被证明是重要的， 在发育过程中调节细胞命运的决定。我们专注于 了解一个POU结构域基因XIPAR 2的功能， 神经发育XIPs 2直接位于神经元的下游， noggin的诱导信号通路。我们目前的目标是确定 XIPv 6 2启动子中的头蛋白诱导元件。XIP 2的时间和 表达的空间模式表明，它可能是调节在 神经诱导过程腹外胚层中XIPs 2的错误表达 导致细胞命运从表皮表型改变为神经元表型， 展示了XIPP 2作为主调节器的潜在作用， 神经发生我们已经研究了XIPP 2在Spemann的组织者中的作用 通过在胚胎中过表达XIPb 2基因产物。过表达 XIPs 2的表达导致了在原肠胚形成中背侧基因功能的抑制， 非洲爪蟾胚胎，导致“无头”表型。我们还 特征在于一个新的POU基因在斑马鱼，太极。表达 太极拳在发展过程中的模式和成人大脑是一致的 其潜在的作用是规范建立和/或维持 神经干细胞太极表达与增殖， 大脑中未分化的细胞。这个细胞群可以被标记为 通过BrdU，并且不表达两种神经分化标记物， 乙酰化微管蛋白和神经丝蛋白。我们正在描述这些 细胞进一步使用与太极共表达的另一种标志物，NRP-1 (an RNA结合蛋白）。为了进一步了解干细胞在 在哺乳动物发育过程中，我们正在尝试克隆小鼠的同源物 太极拳。

POU transcription factors have been shown to be important in the regulation of cell fate decisions during development. We have focused on understanding the function of one POU domain gene, XIPOU 2 , in early neural development. XIPOU 2 is immediately downstream in the neural inductive signaling pathway for noggin. Our current goal is to identify noggin inducible elements in the XIPOU 2 promoter. XIPOU 2's temporal and spatial pattern of expression suggests that it may be regulatory in the neural inductive process. Misexpressing XIPOU 2 in ventral ectoderm results in a cell fate change from an epidermal to neuronal phenotype, demonstrating XIPOU 2's potential role as a master regulator in neurogenesis. We have examined the role of XIPOU 2 in Spemann's organizer by overexpressing the XIPOU 2 gene product in embryos. The overexpression of XIPOU 2 leads to a suppression of dorsal gene function in gastrulating Xenopus embryos, which results in a "headless" phenotype. We have also characterized a novel POU gene in zebrafish, taichi. The expression pattern of taichi during development and in the adult brain is consistent with its potential role in regulating the establishment and/or maintenance of neural stem cells. Taichi expression is associated with proliferating, non-differentiated cells of the brain. This cell population can be labeled by BrdU, and does not express two markers of neural differentiation, acetylated tubulin and neurofilament protein. We are characterizing these cells further using another marker that is co-expressed with taichi, NRP-1 (an RNA binding protein). To further understand the role of stem cells in mammalian development, we are attempting to clone a mouse homolog of taichi.