The role of FAT10 in the pathogenesis of HIV-associated nephropathy

FAT10在HIV相关肾病发病机制中的作用

• 批准号: 7988984
• 负责人: MICHAEL J ROSS
• 金额: $ 10.3万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-11-26 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7988984
• 关键词: AIDS-Associated Nephropathy; African; African American; Alleles; Apoptosis; Biopsy Specimen; Breeding; Cells; Chronic Kidney Failure; Code; Development; Disease; Disease Progression; Epithelial; Epithelial Cells; Exons; FAT gene; Gene Deletion; Genes; Genetic; Genetic Polymorphism; HIV; HIV Infections; HIV-1; Haplotypes; Human; In Vitro; Individual; Inflammation; Kidney; Kidney Diseases; Kidney Failure; Knockout Mice; Laboratories; Lead; Mediator of activation protein; Mus; N-terminal; NF-kappa B; Pathogenesis; Patients; Phenotype; Phosphotransferases; Predisposition; Production; Proteins; Research Personnel; Risk; Role; Signal Transduction; Single Nucleotide Polymorphism; Stimulus; Testing; Transgenic Mice; Transgenic Model; Tubular formation; UBD protein; Ubiquitin Like Proteins; Up-Regulation; Variant; insight; knock-down; novel; prevent; programs; small hairpin RNA; vector

DESCRIPTION (provided by applicant): Tubulointerstitial renal disease is an important component of the pathobiology of HIV-associated nephropathy (HIVAN), the most common cause of chronic renal failure in HIV-infected individuals. In HIVAN, HIV infection of renal tubular epithelial cells (RTECs) leads to dysregulated apoptosis and production of proinflammatory molecules, both of which contribute importantly to progressive renal failure. HIVAN occurs almost exclusively in people of African ancestry and the genetic background of the individual is a critical determinant of whether renal epithelial infection by HIV will lead to progressive renal disease. We have recently demonstrated that the ubiquitin-like protein FAT10 is highly upregulated by HIV-infection of human RTECs in vitro and in HIVAN biopsy specimens, that FAT10 expression induces apoptosis in RTECs, and that preventing FAT10 expression with shRNA constructs ameliorates HIV-induced RTEC apoptosis. Preliminary studies in our laboratory have also demonstrated that FAT10 expression upregulates NF-KB signaling in human RTECs and may therefore induce production of proinflammatory mediators by these cells. We have identified four alleles of the FAT10 gene, one of which is significantly more common in patients with HIVAN. Since RTEC apoptosis and production of proinflammatory mediators by RTECs are important factors in HIVAN pathogenesis, we hypothesize that polymorphisms in the FAT10 gene alter its ability to induce RTEC apoptosis and NF-kB activation in RTECs. We will test these hypotheses in the following three Specific Aims: 1: To determine the effects of nonsynonymous FAT10 SNPs in FAT10 upon its subcellular localization and proapoptotic function. In this aim, we will determine how the four variants of the FAT10 protein differ in their subcellular localization and their ability to induce apoptosis. 2: To define the role of FAT10 in NF-KB signaling in human renal tubular epithelial cells and to determine if the FAT10 alleles differ in their ability to stimulate NF-KB signaling. In aim 2, we will study the mechanisms by FAT10 activates NF-KB signaling. 3: To determine whether FAT10 expression is necessary for the development of the HIVAN phenotype in the HIV-1 transgenic model of HIVAN. In aim 3, we will breed FAT10 knockout mice with HIV-1 transgenic mice and study the effect of FAT gene deletion upon the HIVAN phenotype. These studies will elucidate novel mechanisms of disease progression in HIVAN.

描述（由申请人提供）：肾小管间质性肾病是 HIV 相关肾病 (HIVAN) 病理学的重要组成部分，是 HIV 感染者慢性肾功能衰竭的最常见原因。在 HIVAN 中，肾小管上皮细胞 (RTEC) 的 HIV 感染会导致细胞凋亡失调和促炎分子产生，这两者都会对进行性肾功能衰竭产生重要影响。 HIVAN 几乎只发生在非洲血统的人群中，个体的遗传背景是 HIV 肾上皮感染是否会导致进行性肾病的关键决定因素。我们最近证明，在体外和 HIVAN 活检标本中，人类 RTEC 的 HIV 感染会高度上调泛素样蛋白 FAT10，FAT10 表达会诱导 RTEC 细胞凋亡，并且用 shRNA 构建体阻止 FAT10 表达可改善 HIV 诱导的 RTEC细胞凋亡。我们实验室的初步研究还表明，FAT10 表达上调人类 RTEC 中的 NF-KB 信号传导，因此可能诱导这些细胞产生促炎介质。我们已经确定了 FAT10 基因的四个等位基因，其中之一在 HIVAN 患者中更为常见。由于 RTEC 凋亡和 RTEC 产生促炎介质是 HIVAN 发病机制的重要因素，因此我们假设 FAT10 基因的多态性改变了其诱导 RTEC 凋亡和 RTEC 中 NF-kB 激活的能力。我们将在以下三个具体目标中检验这些假设： 1：确定 FAT10 中非同义 FAT10 SNP 对其亚细胞定位和促凋亡功能的影响。为此，我们将确定 FAT10 蛋白的四种变体在亚细胞定位和诱导细胞凋亡的能力方面有何不同。图 2：定义 FAT10 在人肾小管上皮细胞 NF-KB 信号传导中的作用，并确定 FAT10 等位基因刺激 NF-KB 信号传导的能力是否存在差异。在目标2中，我们将研究FAT10激活NF-KB信号传导的机制。图3：确定FAT10表达对于HIVAN的HIV-1转基因模型中HIVAN表型的发展是否是必需的。在目标3中，我们将用HIV-1转基因小鼠培育FAT10敲除小鼠，并研究FAT基因缺失对HIVAN表型的影响。这些研究将阐明 HIVAN 疾病进展的新机制。