Genetic and Molecular Analyses of Protein Biogenesis in the Neuroretina

神经视网膜蛋白质生物发生的遗传和分子分析

• 批准号: 7986400
• 负责人: PAULO A FERREIRA
• 金额: $ 39万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7986400
• 关键词: 26S proteasome; Achievement; Affect; Age; Aging; Ally; Binding Proteins; Biogenesis; Biological; Cells; Complex; Coupled; Cyclophilins; Disease; Ectopic Expression; Equilibrium; Figs - dietary; Ganglia; Goals; Homeostasis; Human; Impairment; Lead; Life; Light; Link; Molecular; Molecular Genetics; Mus; Mutate; Myxoid cyst; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Opsin; Oxidative Stress; Pathogenesis; Peptidylprolyl Isomerase; Phenotype; Photoreceptors; Pigment Epithelium; Process; Proteins; Proteolysis; Regulation; Research; Retina; Retinal; Retinal Cone; Retinal Degeneration; Retinal Diseases; Role; Running; Stress; Structure of retinal pigment epithelium; System; Testing; Therapeutic; Transgenic Mice; Transgenic Organisms; Ubiquitin; Up-Regulation; Vertebrate Photoreceptors; Vision; Vision Disorders; age related; cell type; chaperone machinery; interdisciplinary approach; loss of function; loss of function mutation; mouse model; multicatalytic endopeptidase complex; neuroprotection; new therapeutic target; novel; prevent; protein degradation; protein folding; protein function; public health relevance; rat Ran 2 protein; retinal neuron; sex

DESCRIPTION (provided by applicant): The deregulation of the ubiquitin-proteasome system (UPS) is a hallmark feature of many neurodegenerative disorders, including retinal degenerations, which involve misfolding and deregulation of protein turnover in photoreceptors. Our long-range objective is to understand the role of a regulatory complex of the UPS- chaperone machinery in controlling substrate degradation and folding and use this information to identify targets for novel therapeutic strategies, which presently lack efficacy toward selective biological and disease processes of the UPS. The goal of this proposal is to understand the molecular and intracellular mechanisms that sustain the balance between turnover and biogenesis of proteins, two tightly coupled processes that are vital for retinal-neuron function and survival and that are implicated in the pathogenesis of a wide variety of neuro-visual disorders of the human. Achievement of this goal will allow us and others to identify novel pharmacological targets and develop therapeutic strategies to manipulate the UPS-chaperone machinery, prevent the toxic deregulation of normal or expression of mutated proteins under various retinal disease states and aging manifestations causing the impairment of the UPS-chaperone machinery and neuro-visual function. The proposed research builds upon our prior research findings which demonstrated that substrates are presented to the proteasome upon synthesis and that the activity of the proteasome is regulated and compartmentalized in the cell. Ran-binding protein 2 (RanBP2) via two distinct domains, the cyclophilin-like (CLD) and cyclophilin (CY) domains, is a key controller of such processes. This proposal tests our overall hypothesis that RanBP2 and its CLD and CY domains control two tightly coupled processes, the UPS-dependent turnover and biogenesis of selective proteins that are critical to the function and survival of selective retinal neurons and retinal pigment epithelium (RPE) cells under normal and pathophysiological conditions. We will test this hypothesis by accomplishing the following specific aims, which focus on the mechanistic roles of RanBP2, and its CLD and CY domains, in the regulation of protein homeostasis and survival of selective retinal neurons under normal and disease stress conditions. Aim 1. Test the hypothesis that loss-of-function of RanBP2 has differential biological and pathological effects among retinal neurons, some of which may be essential to the viability or protein homeostasis of such neurons. Aim 2. Test the hypothesis that selective loss-of-function of the CLD activity of RanBP2 up-regulates selective functions of the UPS that are critical to homeostasis of selective retinal proteins, function and survival of retinal neurons and RPE cells. Aim 3. Test the hypothesis that the cis-trans prolyl isomerase (PPIase) activity in the CY domain of RanBP2 controls the biogenesis of selective proteins that are critical to the function or survival of retinal neurons and RPE cells. PUBLIC HEALTH RELEVANCE: The modulation of protein degradation and biogenesis in the retina is of vital importance to its function. Impairment of these processes is known to underlie the pathogenesis of several degenerative and aging disorders affecting retinal neurons. The proposal aims at elucidating the role of Ran-binding protein 2 in protein homeostasis and allied pathohysiological states in the retina.

描述（由申请人提供）：泛素-蛋白酶体系统（UPS）的失调是许多神经退行性疾病的标志性特征，包括视网膜变性，其涉及光感受器中蛋白质周转的错误折叠和失调。我们的长期目标是了解UPS-分子伴侣机制的调节复合物在控制底物降解和折叠中的作用，并使用该信息来鉴定新的治疗策略的靶点，该治疗策略目前对UPS的选择性生物学和疾病过程缺乏功效。该提案的目标是了解维持蛋白质周转和生物发生之间平衡的分子和细胞内机制，这两个紧密耦合的过程对视网膜神经元功能和存活至关重要，并且与人类各种神经视觉障碍的发病机制有关。这一目标的实现将使我们和其他人能够鉴定新的药理学靶点并开发治疗策略以操纵UPS-伴侣机制，防止在各种视网膜疾病状态和衰老表现下正常蛋白质或突变蛋白质表达的毒性失调，从而导致UPS-伴侣机制和神经视觉功能的损害。拟议的研究建立在我们以前的研究结果，这表明，底物的蛋白酶体合成后，蛋白酶体的活性是调节和划分在细胞中。Ran-binding protein 2（RanBP 2）通过两个不同的结构域，亲环蛋白样（CLD）和亲环蛋白（CY）结构域，是这些过程的关键控制器。该提议测试了我们的总体假设，即RanBP 2及其CLD和CY结构域控制两个紧密耦合的过程，即对正常和病理生理条件下选择性视网膜神经元和视网膜色素上皮（RPE）细胞的功能和存活至关重要的选择性蛋白质的UPS依赖性周转和生物发生。我们将通过完成以下具体目标来测试这一假设，这些目标集中在RanBP 2及其CLD和CY结构域在正常和疾病应激条件下调节蛋白质稳态和选择性视网膜神经元存活中的机制作用。目标1.检验RanBP 2功能丧失在视网膜神经元中具有不同的生物学和病理学效应的假设，其中一些可能对这些神经元的活力或蛋白质稳态至关重要。目标2.检验RanBP 2的CLD活性的选择性功能丧失上调UPS的选择性功能的假设，所述UPS的选择性功能对于选择性视网膜蛋白的稳态、视网膜神经元和RPE细胞的功能和存活是关键的。目标3.检验RanBP 2的CY结构域中的顺式-反式脯氨酰异构酶（PPI酶）活性控制对视网膜神经元和RPE细胞的功能或存活至关重要的选择性蛋白质的生物发生的假设。 公共卫生相关性：视网膜中蛋白质降解和生物合成的调节对其功能至关重要。已知这些过程的损伤是影响视网膜神经元的几种退行性和衰老性疾病的发病机制的基础。该提案旨在阐明Ran结合蛋白2在视网膜蛋白质稳态和相关病理生理状态中的作用。