HCMV US28 Signal Transduction by Betaarrestin proteins

Betaarrestin 蛋白的 HCMV US28 信号转导

• 批准号: 6987737
• 负责人: WILLIAM E MILLER
• 金额: $ 22.83万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6987737
• 关键词: Herpes simplex disease; arrestins; biological signal transduction; cell line; cell migration; cell surface receptors; cytomegalovirus; gene mutation; gene targeting; genetic regulation; host organism interaction; immunomodulators; intermolecular interaction; muscle cells; opportunistic infections; pathologic process; phosphorylation; protein structure function; receptor expression; receptor sensitivity; smooth muscle; virus genetics

DESCRIPTION (provided by applicant): Human Cytomegalovirus (HCMV) infection is a leading cause of viral associated congenital birth defects and has proven to be a significant public health problem in organ transplant recipients as well as in individuals with AIDS. Accumulating evidence indicates that there may be a relationship between HCMV and the development of vascular disease. The interplay between HCMV and the immune system is a critical factor in the events leading to initiation of disease. Interestingly, HCMV encodes several genes that appear to modulate immune system function. One of these genes, termed US28, is homologous to the mammalian chemokine G-protein coupled receptors (GPCRs). While progress has recently been made in the identification of signaling pathways downstream of US28, very little is known regarding the molecular details proximal to US28 that contribute to the activation of signaling pathways. The objective of this proposal is to identify specific receptor properties and molecular events proximal to US28 that are critical for activation of known signal transduction pathways. We hypothesize that a detailed study of the molecular interactions of betaarrestin proteins with US28 will generate novel insights into the regulation of US28 signaling. The betaarrestins were originally identified in the context of termination of "traditional" G-protein signaling to effectors such as adenylyl cyclases and phospholipases. This termination process, also known as desensitization, involves receptor phosphorylation by GRKs and binding of betarrestin proteins. It is now clear that the betaarrestins simultaneously function as adapter/scaffold molecules to recruit signaling proteins to receptors in order to activate additional "non-traditional" signaling pathways. We have identified a US28 mutant that is unable to interact with betaarrestin and have generated a significant amount of preliminary data regarding signaling from this mutant. We propose to analyze the involvement of betaarrestin proteins in US28 signaling in order to gain a greater understanding of the proximal events leading to activation of US28 signaling pathways. To accomplish this goal, we propose three specific aims. First, we will characterize "traditional" signaling from this US28 mutant in the context of HCMV infection and will analyze how this mutant affects the ability of US28 to stimulate smooth muscle cell migration. Second, we will analyze "non-traditional" signaling pathways from US28 potentially mediated by betaarrestin recruitment to the US28 carboxy terminal regulatory domain. Third, we will analyze US28 signaling in cells deficient for betaarrestin expression in order to specifically define the involvement of betaarrestins. Our preliminary data indicate that US28 engages ?arrestin proteins suggesting that we will be able to make rapid progress toward our goal of defining the role of these important regulatory proteins in US28 signaling. These studies will identify mechanisms regulating US28 mediated signal transduction and will enhance our understanding of how US28 participates in pathogenesis and initiation of HCMV disease.

描述（由申请人提供）：人类巨细胞病毒（HCMV）感染是病毒相关的先天性先天性先天缺陷的主要原因，事实证明，在器官移植受者以及艾滋病患者中是一个重大的公共卫生问题。积累的证据表明，HCMV与血管疾病的发展之间可能存在关系。 HCMV与免疫系统之间的相互作用是导致疾病启动的事件的关键因素。有趣的是，HCMV编码几个似乎调节免疫系统功能的基因。这些基因之一称为US28，与哺乳动物趋化因子G蛋白偶联受体（GPCR）同源。尽管最近在识别US28下游的信号通路方面取得了进展，但对于近距离US28的分子细节而言，鲜有助于信号通路的激活。该提案的目的是确定邻近US28的特定受体特性和分子事件，这对于激活已知信号转导途径至关重要。我们假设对Betaarrestin蛋白与US28的分子相互作用的详细研究将对US28信号的调节产生新的见解。贝塔雷蛋白最初是在终止对腺苷酸环化酶和磷脂酶等效应子终止的“传统” G蛋白信号传导的背景下鉴定的。这种终止过程（也称为脱敏）涉及GRK的受体磷酸化和β蛋白质的结合。现在很明显，βarrestin同时用作衔接子/支架分子来募集信号蛋白到受体，以激活其他“非传统”信号通路。我们已经确定了一个无法与betaarrestin相互作用的US28突变体，并产生了有关该突变体信号传导的大量初步数据。我们建议分析βarartin蛋白在US28信号传导中的参与，以便对导致US28信号通路激活的近端事件有更深入的了解。为了实现这一目标，我们提出了三个具体目标。首先，我们将在HCMV感染的背景下从该US28突变体中表征“传统”信号传导，并将分析该突变体如何影响US28刺激平滑肌细胞迁移的能力。其次，我们将分析从US28的“非传统”信号通路可能通过betaarrestin募集到US28羧基末端调节域而介导的。第三，我们将分析缺乏贝塔雷斯汀表达的细胞中的US28信号传导，以专门定义βarartins的参与。 我们的初步数据表明US28参与？逮捕蛋白表明我们将能够快速进步，以定义这些重要调节蛋白在US28信号传导中的作用。这些研究将确定调节US28介导的信号转导的机制，并将增强我们对US28如何参与HCMV疾病的发病机理和启动的理解。