MOLECULAR GENETICS OF A LENS INTRINSIC MEMBRANE PROTEIN

描述：(调查员摘要)。人工晶状体是一种无血管的半固态器官，其功能是将入射光线折射到视网膜上。伴随这一功能的是镜片保持透明的必要性。晶状体透明度的丧失通常是永久性的，被称为白内障。细胞和器官的功能，如获得维持健康、透明的晶状体状态、处理细胞废物和维持膜的整体稳定性所需的营养物质，是通过晶状体细胞膜内的特定蛋白质或蛋白质组来实现的。适当地控制这些蛋白的表达及其随后的功能对于晶状体存活和维持透明度是至关重要的。调节晶状体中这些膜蛋白的机制目前尚不清楚。本项目的目的是了解晶状体纤维细胞膜蛋白MP19基因(LIM2)的调控。为了实现这一目标，私人情报局将调查以下主题：a)。目的研究小鼠白内障突变型和人类先天性核性白内障的特征及其与晶状体膜LIM2基因的关系。采用转基因小鼠技术模拟TO白内障模型，研究MP19的功能。b)。利用CAT报告基因构建的瞬时转基因技术，确定人LIM2基因(顺式元件)转录活性的调控区域(S)。c)。识别蛋白质：使用凝胶迁移率改变和DNA足迹程序识别与LIM2基本启动子区域和上游顺式元件相关的DNA相互作用(反式因子)。d)。研究LIM2基因上游区域的甲基化模式，以确定关键顺式元件甲基化是否影响LIM2基因的功能。这些研究将使人们更好地了解MP19在维持晶状体透明度中的作用，以及它在白内障形成中的可能作用。

DESCRIPTION: (Investigator's Abstract). The ocular lens is an avascular, semisolid organ whose function is to refract incoming light upon the retina. Concomitant with this function is a necessity for the lens to remain transparent. A loss of transparency of the lens is usually permanent and is termed a cataract. Cell and organ functions, such as obtaining nutrients necessary for maintaining the healthy, transparent lens state, for handling of cell waste removal, and for maintenance of overall membrane stability are carried out through select and specific proteins or groupings of proteins within the lens cell membrane. Proper controls on expression of these proteins and their subsequent function is essential for lens survival, and maintenance of transparency. The mechanisms regulating these membrane proteins in the lens are presently unknown. The goal of this project is to understand the regulation of the lens fiber cell membrane protein MP19 gene (LIM2). To achieve this goal, the P.I. will investigate the following topics: a). To characterize the mouse To cataract mutant and the human congenital nuclear cataract and their relationship to the lens membrane LIM2 gene. Using transgenic mouse technology to mimic the To cataract in order to study the function of MP19. b). To determine the region(s) responsible for transcriptional activity of the human LIM2 gene (cis elements), using CAT reporter gene constructs in transient transfection assays. c). Identify protein:DNA interactions (trans factors) associated with the LIM2 basal promoter region and upstream cis elements using gel mobility shift and DNA foot printing procedures. d). To investigate the methylation patterns of LIM2 upstream regions to determine if methylation of critical cis elements serves to control LIM2 gene function. These studies will give a better understanding of the role of MP19 in the maintenance of lens transparency and its possible role in cataract formation.