G protein beta gamma Signaling Systems in Vivo

描述(由申请人提供)：异三聚体G蛋白调节从维持体内平衡到感知环境再到生物体发育的广泛的生物过程。在这个提议中，我们将检验这样一个假设，即组成G蛋白的α、β和伽马亚基的组合可能为如此广泛的生物反应的传播提供一种机制。为此，斑马鱼提供了许多特殊的优势。由于它们表现出与人类和老鼠相似的分子复杂性，斑马鱼提供了一个独特的系统来研究这一重要类别的多亚单位蛋白质的个体发育。整装原位杂交将用于识别各种α、β和伽马亚型表达的时间和地点。随后，使用吗啡反义策略的功能丧失分析将被用来直接将特定的亚型与特定的功能和信号通路联系起来。最后，使用表达方法的互补分析试图挽救功能丧失表型，以确定相关亚型之间存在多大程度的功能冗余。这些信息将为理解G蛋白如何能够接收、整合和处理生物体发育所需的大量信号提供一个框架。由于许多疾病(如癌症、心脏病)与胚胎基因的重新诱导有关，这些信息最终将导致更好的诊断和更有选择的治疗方法。

DESCRIPTION (provided by applicant):The heterotrimeric G proteins regulate a remarkable breadth of biological processes, from maintenance of homeostasis to perception of the environment to development of the organism. In this proposal, we will test the hypothesis that combinatorial association of the alpha, beta and gamma subunits comprising the G proteins may provide a mechanism for the propagation of such a wide range of biological responses. For this purpose, zebrafish offer a number of specific advantages. Because they exhibit a similar molecular complexity to humans and mice, zebrafish provide an unique system to study the ontogeny of this important class of multi-subunit proteins. Whole mount in situ hybridization will be used to identify when and where the various alpha, beta, and gamma subtypes are expressed. Subsequently, loss-of-function analysis using a morpholino anti-sense strategy will be used to directly link a specific subtype to a particular function and signaling pathway. Finally, complementation analysis using an expression approach to try to rescue the loss-of-function phenotype will be used to determine what level of functional redundancy exists among the related subtypes. This information will provide a framework for understanding how the G proteins are able to receive, integrate, and process the multitude of signals required for the development of the organism. Since many diseases (e.g. cancer, heart disease) are associated with re-induction of embryonic genes, this information will eventually lead to the better diagnosis and more selective therapeutic treatments.