Combinatorial signaling in zebrafish development

描述（由申请人提供）：细胞间信号传导在细胞内起着重要作用。 在胚胎发育模式和细胞生长调节中的关键作用 在胚胎和成体中的增殖和存活。通过时间和空间 结合来自不同信号通路的信号，生物体获得了 通过激活靶基因产生复杂的细胞决定 对多种信号因素做出反应。这些组合信号是如何 在分子和细胞水平上使用的大部分都不好 明白该提案的中心问题是：BMPs和WNTs如何工作 共同建立遗传等级，从而形成 后中胚层和神经嵴为了研究这一点，将有三种途径， 以斑马鱼为模型系统进行研究。(1)转基因斑马鱼表达 BMP和Wnt/B-连环蛋白激活剂和抑制剂在热休克控制下将 用于确定何时以及如何使用这些信号来调节 在整个发育过程中形成后中胚层和神经嵴。 (2)对Bmp和Bp-GFP的几个关键靶基因的启动子进行了研究， Wnt/B-连环蛋白信号将被分析，以了解这些信号是如何被激活的。 信号通路最终在转录水平上整合。（三） 微阵列和减法筛选将用于识别 使用斑马鱼突变体， 在Bmp和Wnt信号通路中存在缺陷。一个经过严格挑选的子集 在这些基因中，它们在后中胚层和神经嵴中表达， 将被选中进行进一步的研究，使用转基因鱼的组合， 表达诱导型Bmp和Wnt激活剂和抑制剂，过表达 研究和吗啉代反义寡核苷酸。最后，本分析将 为理解Bmp和Wnt组合如何 信号导致胚胎内特定组织的形成。由于两 BMP和Wnt信号传导参与人类的疾病过程，并且由于 这些信号通路是高度保守的，这项研究将直接 与理解人类疾病机制的相关性。

DESCRIPTION (provided by applicant): Intercellular signaling plays a critical role in patterning embryonic development and in the regulation of cell proliferation and survival in embryos and adults. By temporally and spatially combining signals from different signaling pathways, organisms gain the ability to produce complex cellular decisions through the activation of target genes that respond to multiple signaling factors. How these combinatorial signals are used at the molecular and cellular level is for the most part not well understood. The central question of this proposal is: how do Bmps and Wnts work together to establish genetic hierarchies leading to the formation of the posterior mesoderm and neural crest? To examine this, three avenues will be pursued using zebrafish as a model system. (1) Transgenic zebrafish expressing Bmp and Wnt/B-catenin activators and inhibitors under heat shock control will be used to determine when and how these signals are used to regulate the formation of the posterior mesoderm and neural crest throughout development. (2) The promoters of several key target genes responding to Bmp and Wnt/B-catenin signals will be analyzed in order to understand how these signaling pathways are ultimately integrated at the transcriptional level. (3) Microarray and subtractive screens will be used to identify genes that are regulated by both Bmp and Wnt/B-catenin signals using zebrafish mutants that have defects in the Bmp and Wnt signaling pathways. A critically chosen subset of these genes, which are expressed in the posterior mesoderm and neural crest, will be selected for further study using a combination of the transgenic fish expressing inducible Bmp and Wnt activators and inhibitors, overexpression studies and morpholino antisense oligonucleotides. Finally, this analysis will provide a molecular framework for understanding how combinatorial Bmp and Wnt signals lead to the formation of specific tissues within the embryo. Since both Bmp and Wnt signaling are involved in disease processes in humans, and since these signaling pathways are highly conserved, this research will have direct relevance to understanding mechanisms of human disease.