Genetic Analysis of Snail Superfamily Genes in Mice

描述(申请人提供)：蜗牛超家族基因编码含有锌指的DNA结合蛋白，作为转录抑制因子。这个超家族有两个主要分支：蜗牛家族(由Snai1、2和3基因编码)和Scratch家族(Scrt1和2基因)。这些蛋白是上皮-间充质转化的关键调节因子，也在细胞的增殖、存活和运动中发挥作用。我们对小鼠胚胎发育过程中对蜗牛超家族基因的需求进行了全面的遗传分析。我们在这笔赠款的前几个资助期的工作确立了所有这些基因的无效表型，并证明在Snai1突变体中观察到了最严重的胚胎表型。然而，关于蜗牛超家族基因的要求和作用仍有许多问题。在这项建议中，将利用分子和遗传学的方法来分析蜗牛家族基因在小鼠胚胎发生中所起的作用，并了解导致突变表型的机制。我们已经产生的突变小鼠品系，以及我们将作为这一提议的一部分构建的突变品系，构成了一套独特的试剂，将使我们能够精细地剖析蜗牛家族基因在胚胎发育中的作用。该建议的具体目的是：1)确定SNAI1蛋白在小鼠早期胚胎发育过程中转录抑制的靶点；2)检验GSK3β激酶和BetaTrcp泛素连接酶对SNAI1蛋白的翻译后调控对于Snai1在体内功能至关重要的假说；3)通过确定Snai1、SNAI2和Snai3基因在这些过程中的单独作用，检验蜗牛家族基因对于肌肉发育、生理和再生至关重要的假说；4)评估Snai3冗余与SNAI2和Snai1在肌肉发育、生理和再生过程中的功能。 公共卫生相关性：这项提案的长期目标是了解蜗牛超家族基因在哺乳动物胚胎发育过程中所扮演的角色。蜗牛超家族基因编码含锌指的DNA结合蛋白，作为转录抑制因子。这项研究将进一步加深我们对蜗牛超家族基因在哺乳动物发育中的作用的理解，并将对研究人类正常和异常发育具有重要意义。

DESCRIPTION (provided by applicant): Snail superfamily genes encode zinc finger-containing DNA binding proteins that act as transcriptional repressors. This superfamily has two main branches: the Snail family (encoded by the Snai1, 2 and 3 genes) and the Scratch family (the Scrt1 and 2 genes). These proteins are key regulators of the epithelial- mesenchymal transition, and also play roles in cell proliferation, survival and movement. We have performed a comprehensive genetic analysis of the requirements for Snail superfamily genes during embryonic development in mice. Our work during the prior funding periods of this grant established the null phenotype of all of these genes, and demonstrated that the most severe embryonic phenotype is observed in Snai1 mutants. However, many questions remain about the requirements and roles of Snail superfamily genes. In this proposal, both molecular and genetic approaches will be utilized to analyze the roles played by Snail family genes during embryogenesis in mice, and to understand the mechanisms causing the mutant phenotypes. The mutant mouse strains we have already generated, as well as the mutant strains we will construct as part of this proposal, constitute a unique set of reagents that will permit us to finely dissect the roles of Snail family genes during embryonic development. The specific aims of this proposal are: 1) determine targets for transcriptional repression by the SNAI1 protein during early embryogenesis in mice; 2) test the hypothesis that post- translational regulation of SNAI1 protein by the GSK3beta kinase and the betaTrcp ubiquitin ligase are essential for Snai1 function in vivo; 3) test the hypothesis that Snail family genes are important for muscle development, physiology and regeneration by determining the individual roles of the Snai1, Snai2 and Snai3 genes in these processes; 4) assess Snai3 redundancy with Snai2 and Snai1 function during muscle development, physiology and regeneration. Public Health Relevance: The long-term goal of this proposal is to understand the roles that Snail superfamily genes play during embryonic development in mammals. Snail superfamily genes encode zinc finger-containing DNA binding proteins that act as transcriptional repressors. The studies described in this proposal will further our understanding of the roles played by Snail superfamily genes during mammalian development, and will be relevant to the study of both normal and abnormal human development.