Studies on Protein Lipidation

 描述(申请人提供)：我的实验室开发的脂类化学报告和生物正交连接方法为研究脂类修饰蛋白在生物学中的功能提供了新的机会。我们利用脂肪酸化学报告和生物正交化学蛋白质组学对树突状细胞中的脂肪酰化蛋白进行了蛋白质组学分析，揭示了S蛋白在宿主防御病毒感染中的新作用。我们发现膜-近端半胱氨酸在小鼠IFITM3上的S-脂肪酰化对其膜定位和抗甲型流感病毒活性至关重要。控制人类IFITM蛋白的S-脂肪酰化的机制还没有被评估，将在这项拨款提案中讨论。目的1将评估不同细胞类型/激活状态下人IFITM亚型的S-脂肪酰化水平、位点和功能。目的2描述细胞内与人IFITM3共价结合的脂肪酸的特性。目的3为详细的生化和生物物理研究，描述了IFITM3在体外的位置特异性脂化和重建。确定控制S-脂肪酰化IFITM3功能的机制对于了解宿主免疫是至关重要的，并可能揭示对抗人类病毒感染的新策略。这项资助中描述的化学方法应该为研究脂肪酰化蛋白质提供新的试剂和方法。

 DESCRIPTION (provided by applicant): Lipid chemical reporters and bioorthogonal ligation methods developed by my laboratory have provided new opportunities to investigate the functions of lipid-modified proteins in biology. Our proteomic analysis of fatty-acylated proteins in dendritic cells using fatty acid chemical reporters and bioorthogonal chemical proteomics has revealed a new role for protein S-fatty-acylation in host defense against viral infections. We discovered that S-fatty-acylation of membrane-proximal cysteines on murine IFITM3 is crucial for its membrane localization and antiviral activity against influenza A virus. The mechanisms that control S-fatty-acylation of human IFITM proteins have not been evaluated and will be addressed in this grant proposal. Aim 1 will evaluate the S-fatty-acylation levels, sites and function of human IFITM isoforms in different cell types/states of activation. Aim 2 describes the characterization of fatty acids covalently attached to human IFITM3 in cells. Aim 3 describes site-specific lipidation and reconstitution of IFITM3 in vitro for detailed biochemical and biophysical studies. Determining the mechanisms that control S-fatty-acylation IFITM3 function is crucial for understanding host immunity and may reveal new strategies for combatting virus infection in humans. The chemical approaches described in this grant should provide new reagents and methods for studying fatty-acylated proteins.