GENETIC ANALYSIS OF CHEMOSENSATION IN C ELEGANS

描述：这个项目是为了研究达尔的形成途径 线虫线虫。Dauer是L3幼虫的另一个阶段 线虫的发育是在拥挤条件下进行的。 饿死了。之前在几个实验室的工作已经导致了 达尔诱导型信息素和感觉神经元的鉴定 线虫的头部，调节进入达尔途径的入口。 不适当进入的突变体的遗传上位性分析 Dauer途径在没有信息素的情况下，或者作为替代，无法 在信息素存在的情况下进入达尔途径，已经允许 描述了达尔调节的遗传途径。该计划的目的是 目前的建议是加深对Dauer途径的理解 在细胞和分子水平上。这项研究是一种 了解化学感觉转导和发育调控 环境。 具体目标如下：1)进一步对产品进行表征 Daf-11基因。这已被证明是跨膜的量子基。 环化酶被认为参与了达尔信息素信号的传递 在感觉神经元中。实验包括用抗体进行定位 和转基因，结构/功能分析，以及基因的探索 与一个可能的靶基因Tax-4相互作用，它编码一个cGMP- 激活的离子通道。2)从分子水平克隆和分析两个基因。 Dauer途径：DAF-21，被认为具有密切相关的功能 对于daf-11和daf-14，它们被认为作用于达尔途径的一个分支， 在其他地方，作为转化生长因子β信号通路的一部分。3)延长 感觉下游Dauer通路的已知细胞焦点 激光消融候选中间神经元。中间神经元 选择的将是那些具有适当突触模式的人 与感觉神经元的连接，以及那些被发现表达 达尔遗传途径的分子组成。4)新的基因 达乌尔路径将在基因筛查中被寻找并被放置在达乌尔 上位性分析的路径。5)要测试的电生理研究 响应达尔信息素的信号转导模型将是 通过开发用于感官的膜片钳方法来实现 神经元，或者通过研究人类个体的分子组成 肾上皮细胞。

DESCRIPTION: This project is to study the dauer formation pathway in the nematode C. elegans. The dauer is an alternative L3 larval stage that the developing nematode follows under conditions of crowding and starvation. Previous work in several laboratories has resulted in the identification of a dauer-inducing pheromone and sensory neurons in the head of the nematode that regulate entrance into the dauer pathway. Genetic epistasis analysis of mutants that inappropriately enter the dauer pathway in the absence of pheromone, or alternatively that fail to enter the dauer pathway in the presence of pheromone, has allowed description of a genetic pathway of dauer regulation. The aim of the present proposal is to further the understanding of the dauer pathway at the cellular and molecular levels. This research is a model for understanding chemosensory transduction and regulation of development by the environment. The specific aims are as follows: 1) Further characterize the product of the daf-11 gene. This has been shown to be a transmembrane quanylyl cyclase thought to be involved in transducing the dauer pheromone signal in sensory neurons. Experiments include localization with antibodies and transgenes, structure/function analysis, and exploration of genetic interactions with a possible target gene, tax-4, which encodes a cGMP- activated ion channel. 2) Molecularly clone and analyze two genes of the dauer pathway: daf-21, thought to have a function closely related to daf-11, and daf-14, thought to act in a branch of the dauer pathway, and elsewhere, as part of a TGFbeta signalling pathway. 3) Extend the known cellular focus of the dauer pathway downstream of the sensory neurons by laser ablation of candidate interneurons. Interneurons selected will be those with an appropriate pattern of synaptic connectivity to sensory neurons, and those which are found to express molecular components of the dauer genetic pathway. 4) New genes of the dauer pathway will be sought in a genetic screen and placed in the dauer pathway by epistasis analysis. 5) Electrophysiological studies to test models of signal transduction in response to dauer pheromone will be carried out by developing patch clamping methodology for sensory neurons, or by studying individual molecular components in human epithelial kidney cells.