C. elegans Asymmetric Neuroblast Division

描述(由申请人提供)：开发中的一个基本问题是 如何指定单元格。阐明细胞类型规范的机制是 对于理解和最终治疗人类疾病是必不可少的，例如 癌症，这一过程被改变。一种指定单元类型的机制 是不对称的细胞分裂，一个细胞分裂产生两个子细胞 它们有着截然不同的命运。不对称分布的分子和细胞 信号似乎使分裂的细胞两极分化，但两者之间的联系 机制一直欠缺。火腿-L，一个人的身体互动 不对称分布的分子和保守的Wnt信号分子DSH-2 组件，提供了不对称分子和信号之间的联系。这个 拟议研究的总体目标是确定DSH-2和HAM-1的作用 在不对称的细胞分裂中。该提案有四个具体目标。 1.探讨DSH-2与Ham-1的相互作用。免疫沉淀 将进行实验以确认DSH-2/Ham-1复合体。分子 基因实验将探索蛋白质之间的相互作用是否 它们在不对称分裂中发挥作用所必需的，以及一种蛋白质是否 对于其他分发来说是必要的。 2.检验DSH-2和Ham-1的不对称分布是否 对于它们在不对称细胞分裂中的作用是必要的。本地化领域 将定义这两种蛋白质的位置，错误定位实验将测试 两种蛋白质的不对称分布是否重要 子代细胞的命运。 3.确定哪些蛋白质作用于DSH-2和Ham-1的上游以控制其 不对称分布。利用遗传和免疫细胞化学方法，WNTS 并将测试Frizzleed受体在DSH-2分布中的作用 和火腿-1。然后这些分子将被错误表达以测试是否不对称 信号转导调节DSH-2和Ham-1的分布。 4.确定DSH-2和HAM-1是如何调控细胞不对称分裂的。 使用反向遗传方法，候选基因将被测试在 需要DSH-2和HAM-1的不对称分割。此外，基因 在基因筛查中确定的将被测试Ham-1/DSH-2的作用 路径。作用于该途径的基因将被分子表征。

DESCRIPTION (provided by applicant): A fundamental question in development is how cells are specified. Elucidating mechanisms of cell-type specification is essential to the understanding and eventually treating human diseases, such as cancer, where this process is altered. One mechanism that specifies cell type is Asymmetric Cell Division, where a cell divides to produce two daughter cells that adopt distinct fates. Both asymmetrically distributed molecules and cell signaling appear to polarize dividing cells, but a connection between these two mechanisms has been lacking. A physical interaction between HAM-l, an asymmetrically distributed molecule, and DSH-2, a conserved Wnt signaling component, provides a link between asymmetric molecules and signaling. The overall goal of the proposed research is to define the roles of DSH-2 and HAM-1 in asymmetric cell division. The proposal has four specific aims. 1. To explore the interaction between DSH-2 and HAM-1. Immunoprecipitation experiments will be conducted to confirm a DSH-2/HAM-1 complex. Molecular genetic experiments will probe whether the interaction between the proteins is necessary for their function in asymmetric divisions and whether one protein is necessary for the others distribution. 2. To test whether the asymmetric distributions of DSH-2 and HAM-1 are necessary for their roles in asymmetric cell division. The localization domains of both proteins will be defined, and mislocalization experiments will test whether asymmetric distribution of two proteins is important to specify daughter cell fate. 3. To determine which proteins act upstream of DSH-2 and HAM-1 to control their asymmetric distribution. Using genetic and immunocytochemical approaches, Wnts and Frizzled receptors will be tested for roles in the distribution of DSH-2 and HAM-1. These molecules will then be misexpressed to test whether asymmetric signaling regulates DSH-2 and HAM-1 distribution. 4. To determine how DSH-2 and HAM-1 signal to control asymmetric cell division. Using reverse genetic approaches, candidate genes will be tested for roles in asymmetric divisions that require DSH-2 and HAM-1. In addition, genes identified in genetic screens will be tested for a role the HAM-1 /DSH-2 pathway. Genes that act in the pathway will be characterized molecularly.