Molecular Studies of Osmotic Neural Sensing

描述（由申请人提供）： 目前的项目“渗透神经传感的分子研究”是基于 申请人最近克隆了香草素受体相关的 血管活性离子通道（VR-OAC）及其作为一种可能的 渗透压传感器在下丘脑的中枢神经系统。在这 根据该提案，申请人概述了一系列实验，以进一步探索 这种新分子的功能及其在调节盐 体内平衡。渗透压的稳态是一个重要的先决条件， 所有的活细胞在包括人类在内的脊椎动物中， 压力是所有设定值中最积极防御的设定值 稳态调节系统。渗透压的感应以及 适应性反应-饮酒行为和抗利尿激素的分泌， 解剖学上都位于下丘脑。VR-OAC的最新克隆和 它在下丘脑的定位打开了理解 这种分子水平的自我平衡回路。当前应用程序 描述了一组将进一步表征Vroac基因的实验。 最重要的是，Vroac-/-小鼠将通过基因靶向产生。一般 敲除和中枢神经系统的组织特异性敲除， 提出了将检查这些敲除小鼠系的饮酒行为， 渗透调节、肾功能和体液平衡，包括 调节血压，表达VR-OAC的神经元的轴突投射 和内耳功能VR-OAC在基因恢复方面的潜力 将在突变株中检查体内渗透传感缺陷。 线虫，秀丽隐杆线虫，在渗透感应方面有缺陷。在 在这些研究中，具有这种感知缺陷的osm-9突变蠕虫将被杂交， 过表达大鼠VR-OAC的转基因蠕虫。该实验装置将 允许快速评价VR-OAC的结构-功能关系 体内。通过Vroac基因的缺失和对Vroac基因的分析， Vroac-/-小鼠以及突变蠕虫，申请人打算进行一项研究。 批判性的问题，并发展一个非常强大的工具， 分子遗传学，特别是小鼠基因靶向。被赋予了这些 技术和经验的功能基因组学的Vroac基因， 申请人打算推进他的职业生涯，成为一个独立的初级 调查员

DESCRIPTION (provided by applicant): The current project "Molecular studies of osmotic neural sensing" is based on the recent cloning by the applicant of the vanilloid receptor related osmotically activated ion channel (VR-OAC) and its identification as a possible osmolarity sensor in the hypothalamus of the central nervous system. In this proposal, the applicant outlines a series of experiments to further explore the functions of this novel molecule and its possible role in regulating salt balance in-vivo. Homeostasis of osmotic pressure is a vital prerequisite for all living cells. In vertebrate organisms including humans, systemic osmotic pressure is the most aggressively defended set-point value of all homeostatically regulated systems. Sensing of osmotic pressure as well as the adaptive response - drinking behavior and secretion of antidiuretic hormone - all localize anatomically to the hypothalamus. The recent cloning of VR-OAC and its localization to the hypothalamus opened the door to an understanding of this homeostatic circuit at the molecular level. The current application describes a set of experiments that will characterize the Vroac gene further. Most importantly, Vroac-/- mice will be generated by gene-targeting. A general knockout and a tissue-specific knockout for the central nervous system are proposed. These knockout mouse lines will be examined for drinking behavior, osmotic regulation, kidney function and fluid homeostasis including the regulation of blood pressure, axonal projections of VR-OAC expressing neurons and inner ear function. The potential of VR-OAC to restore genetically defective osmotic sensing in-vivo will be examined in a mutant strain of the roundworm, Caenorhabditis elegans, that has defects in osmotic sensing. In these studies, osm-9 mutant worms with such sensing defects will be crossed to transgenic worms that overexpress rat VR-OAC. This experimental set-up will allow for a rapid evaluation of structure-function relationships of VR-OAC in-vivo. By means of the proposed deletion of the Vroac gene and analysis ot Vroac-/- mice as well as the mutant worms, the applicant intends to pursue a critical question and develop a firm grasp of the immensely powerful tools of molecular genetics and in particular, mouse gene-targeting. Endowed with these techniques and the experience of functional genomics of the Vroac gene, the applicant intends to advance his career and become an independent junior investigator.