IN VIVO ROLE OF CAVEOLIN-1 IN KNOCKOUT AND TRANSGENIC MOUSE RETINA

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。本项目的目的是研究小窝蛋白-1 （Cav-1）的体内功能，Cav-1是一种定位于光感受器细胞膜中专门的脂筏结构域的蛋白质。Cav-1是细胞信号转导和膜运输的重要调节因子。然而，其在视网膜细胞功能中的作用尚不清楚。在脂筏的生化制备过程中，参与光感受器结构和功能的几种重要蛋白与Cav-1协同作用。其中包括与视网膜疾病明显相关的蛋白质，包括cgmp -磷酸二酯酶、转导蛋白、ROM-1、视紫红质和鸟苷酸环化酶。许多这些蛋白质以活性或信号依赖的方式与脂筏相关，表明这种关联的功能相关性。这些蛋白定位于脂筏的机制以及它们的活性如何在这些区域内被调节尚不清楚。Cav-1可能介导筏内信号复合物的组织和/或可能组织光感受器膜的脂质环境。为了解决Cav-1在体内的功能，我们已经开始研究动物模型，以深入了解Cav-1在视网膜中的功能：(1)Cav-1全球缺失小鼠和(2)在杆状光感受器中表达Cav-1的转基因青蛙（非洲爪蟾）。初步结果显示Cav-1缺失小鼠的视网膜表型。利用这些体内系统，我们建议研究Cav-1表达对基本光感受器过程的直接影响。本课题将研究Cav-1在调节光导蛋白活性和光感受器膜环境中的作用。光感受器的膜组成是光传导的重要调节剂。该项目中使用的多种分析方法，包括荧光/共聚焦显微镜、生物化学、分子生物学和电生理学，将深入了解这种重要蛋白质的体内功能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goal of this project is to examine the in vivo function of caveolin-1 (Cav-1), a protein that localizes to specialized lipid raft domains in cell membranes of photoreceptors. Cav-1 is an important regulator of signal transduction and membrane trafficking in cells. However, its role in retinal cell function is unknown. Several important proteins involved in photoreceptor structure and function cofractionate with Cav-1 in biochemical preparations of lipid rafts. These include proteins that are clearly associated with retinal disease including the cGMP-phosphodiesterase, transducin, ROM-1, rhodopsin, and guanylate cyclase. Many of these proteins associate with lipid rafts in an activity- or signal-dependent manner suggesting functional relevance to such associations. The mechanisms by which these proteins localize to lipid rafts and how their activities are modulated within these domains is not well understood. Cav-1 may mediate the organization of signaling complexes within rafts and/or may organize the lipid environment of photoreceptor membranes. To address the function of Cav-1 in vivo, we have begun to study animal models that will provide insight into the function of Cav-1 in the retina: (1) Cav-1 global null mice and (2) transgenic frogs (Xenopus laevis) that express Cav-1 in rod photoreceptors. Preliminary results suggest a retinal phenotype in Cav-1 null mice. Using these in vivo systems we propose to examine the direct effect of Cav-1 expression on fundamental photoreceptor processes. In this project, the function of Cav-1 in modulating the activities of phototransduction proteins and in regulating the membrane environment of photoreceptors will be studied. The membrane composition of photoreceptors is an essential modulator of phototransduction. The multiple analytical approaches used in the proposed project including, fluorescence/confocal microscopy, biochemistry, molecular biology and electrophysiology will provide insight into the in vivo function of this important protein.