Proteasome Function in the Aging Retina

本申请是为了响应2009年美国复苏和再投资法案的一部分，为期两年的潜在支持。具体目标已从最初的建议修改，以适应2年的资金。蛋白酶体复合物在细胞活力所必需的过程中起着重要作用，如细胞周期调节、信号转导和基因表达的控制以及氧化和错误折叠蛋白质的降解。两种类型的蛋白酶体，组成型和免疫蛋白酶体，已被描述。拟议的工作调查影响视网膜细胞中两种蛋白酶体亚型之间平衡的因素，并测试有关视网膜稳态对免疫蛋白酶体功能依赖性的具体假设。潜在的假设是免疫蛋白酶体的功能， 对于处于压力下的细胞至关重要;该假说将免疫蛋白酶体与先天免疫系统及其在组织稳态中的作用联系起来，但并不将其限制于免疫功能。目的1验证免疫蛋白酶体在正常条件下维持视网膜健康的假设。该方法是使用缺乏免疫蛋白酶体的两个（lmp 7/-/mecl-r/-）催化亚基的免疫蛋白酶体缺陷小鼠（L7 M1小鼠），通过比较年龄匹配的WT和L7 M1小鼠（1至24个月）来确定抑制免疫蛋白酶体表达的后果。目的2测试的假设，即无法使免疫蛋白酶体敏感的视网膜更不利的后果后，非常的压力。在两种不同类型的损伤模型（恒定光照和持续光照）后，WT和L7 M1小鼠中的损伤程度是相同的。 视神经挤压）将被测试。这些实验的结果将有助于验证免疫蛋白酶体是视网膜应激反应的重要组成部分，并在维持视网膜健康方面发挥重要作用。

This application is in response to potential support for two years as part of the American Recovery and Reinvestment Act of 2009. The Specific Aims have been modified from the original proposal to fit 2 years of funding. The proteasome complex plays a fundamental role in processes essential for cell viability, such as cell cycle regulation, control of signal transduction and gene expression, and the degradation of oxidized and misfolded proteins. Two types of proteasomes, the constitutive and immunoproteasomes, have been described. The proposed work investigates factors that influence the balance between the two proteasome subtypes in cells of the retina, and tests specific hypotheses regarding the dependence of retinal homeostasis on immunoproteasome function. The underlying hypothesis is that immunoproteasome performs functions that are vital to cells under stress; this hypothesis links the immunoproteasome to the innate immune system, and its role in tissue homeostasis, but does not limit it to immunological functions. Aim 1 tests the hypothesis that immunoproteasome is critical for maintaining a healthy retina under normal conditions in vivo. The approach is to use immunoproteasome-deficient mice lacking two (lmp7/-/mecl-r/-) catalytic subunits of immunoproteasome (L7Ml mice) to determine the consequences of inhibiting immunoproteasome expression by comparing age-matched WT and L7Ml mice, ages 1 to 24 months. Aim 2 tests the hypothesis that the inability to make immunoproteasome sensitizes the retina to more adverse outcomes following extraordinary stress. The extent of damage in WT and L7Ml mice after two distinct types of injury models (constant light and optic nerve crush) will be tested. Results from these experiments will help verify that immunoproteasome is an essential component of the retinal stress response and plays a fundamental role in maintaining retinal health.