Tyrosine Sulfation and Chemokine Receptor Function

酪氨酸硫酸化和趋化因子受体功能

• 批准号: 6664727
• 负责人: KEVIN L MOORE
• 金额: $ 30.9万
• 依托单位: OKLAHOMA MEDICAL RESEARCH FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-29 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6664727
• 关键词: calcium flux; chemokine; chemotaxis; cytokine receptors; gene targeting; hydrolysis; immunoprecipitation; laboratory mouse; posttranslational modifications; protein structure function; sulfation; sulfotransferase; tyrosine

DESCRIPTION (provided by applicant): Tyrosine sulfation is a post-translational modification mediated by one of two Golgi tyrosylprotein sulfotransferases (TPST-1 and TPST-2), that catalyze the transfer of sulfate from PAPS to lumenally oriented tyrosine residues in secreted and transmembrane proteins. A small number of proteins are known to be tyrosine sulfated in man, including certain adhesion molecules, coagulation factors, serpins, extracellular matrix proteins, and hormones and some of these require sulfation for optimal function. Recently, several G-protein-coupled receptors (GPCRs), including the chemokine receptors CCR2B, CXCR4, CCR5, and CX3CR1, the C5a receptor, and the TSH receptor were shown to be tyrosine sulfated on their N-terminal domains and to require sulfation for optimal binding of their cognate ligands. However, all current data on GPCR sulfation are based on human receptors expressed in cell lines. Thus, the importance of GPCR sulfation in ligand binding in native cells and its relevance in vivo is uncertain. The N-terminal domains of all known chemokine receptors (CCRs) contain tyrosine residues in the context of several flanking acidic amino acids, features shared by all known tyrosine sulfated proteins. This suggests that all CCRs may be tyrosine sulfated and require sulfation for chemokine binding. The goal of this application is to systematically examine whether mouse CCRs are tyrosine sulfated and to explore the role of tyrosine sulfation in CCR function in vitro and in vivo. The following specific aims are proposed. Aim 1 -Determine if the known CCRs are tyrosine sulfated in the mouse. Aim 2 - Determine if CCR sulfation is required for optimal function in vitro by assessing chemokine-induced responses of cells derived fromTpst1-/- and Tpst2-/- mice. Aim 3 - Determine the biological relevance of deficient sulfation of CCRs in vivo by examining biological responses to inflammatory challenges that normally require a particular CCR are abnormal in Tpst1-/- and Tpst2-/- mice. Chemokines and their receptors play crucial roles in a variety of pathophysiological processes, such as bacterial and viral infection (i.e. HIV/AIDS), allergy, atherosclerosis, malignancy, and various autoimmune and chronic inflammatory diseases. These studies will provide new insights into the importance of tyrosine sulfation in innate and adaptive host responses during a wide variety of pathophysiological processes.

描述（由申请人提供）：酪氨酸硫酸化是由两种高尔基酪蛋白酪蛋白硫代转移酶（TPST-1和TPST-2）介导的翻译后修饰，可催化硫酸盐从PAPS中转移到分泌和跨膜蛋白中的纯净酪氨酸残基。已知少数蛋白质被硫化在人中硫酸硫酸，包括某些粘附分子，凝结因子，Serpins，细胞外基质蛋白和激素，其中一些需要硫化才能达到最佳功能。最近，几种G蛋白偶联受体（GPCR），包括趋化因子受体CCR2B，CXCR4，CCR5和CX3CR1，C5A受体，C5A受体和TSH受体被证明是在其N末端域上硫酸硫酸硫酸含量的酪氨酸，并需要硫酸含量的硫酸脂肪结合。但是，所有有关GPCR硫化的当前数据均基于细胞系中表达的人体受体。因此，GPCR硫酸盐在天然细胞中的结合中的重要性及其在体内的相关性尚不确定。在几个侧翼酸性氨基酸的背景下，所有已知的趋化因子受体（CCR）的N末端结构域均包含酪氨酸残基，这是所有已知的酪氨酸硫酸盐蛋白共享的特征。这表明所有CCR可能都是酪氨酸硫酸硫磺素，并且需要硫化以进行趋化因子结合。该应用的目的是系统地检查小鼠CCR是否被酪氨酸硫酸化，并探索酪氨酸硫酸化在体外和体内CCR功能中的作用。提出了以下特定目标。 AIM 1-确定如果已知的CCR是在小鼠中硫酸硫酸的。 AIM 2-通过评估趋化因子诱导的从TPST1 - / - 和TPST2 - / - 小鼠衍生的细胞的反应，确定在体外最佳功能是否需要CCR硫酸化。 AIM 3-通过检查通常需要特定CCR的炎症挑战的生物学反应在TPST1 - / - 和TPST2 - / - 小鼠中异常，确定了CCR缺乏CCR的生物学相关性。 趋化因子及其受体在多种病理生理过程中起着至关重要的作用，例如细菌和病毒感染（即HIV/AIDS），过敏，动脉粥样硬化，恶性肿瘤以及各种自身免疫性和慢性炎性疾病。这些研究将提供有关酪氨酸硫酸在多种病理生理过程中先天和适应性宿主反应中的重要性的新见解。