Analysis of lipolytic trafficking in adipocytes

描述(由申请人提供)：脂质的储存和动员是基本的细胞过程，其失调导致许多疾病，包括糖尿病、动脉粥样硬化和心肌病。这一提议的中心假设是，受调控的脂解涉及脂肪酶和共激活剂有序地转移到由特定脂滴支架蛋白组织的专门的脂滴结构。最近的研究表明，Perilipin A(Protein Perilipin A，PLIN)是一种脂滴支架蛋白，协调脂解蛋白在脂肪细胞中的运输。这项拟议的工作试图建立在这些结果的基础上，并将表征在体外和原位PKA刺激的脂肪细胞脂解过程中这些脂解蛋白之间相互作用的确切时间顺序。与脂肪细胞脂肪分解相比，肌肉中脂肪分解的组织方式知之甚少；然而，我们的初步数据表明，Mldp是一种新的脂滴蛋白，它在肌肉中组织脂肪分解以促进细胞内脂肪酸的氧化。使用一组新的试剂和技术，我们建议解剖模型肌细胞和真实肌纤维中的脂解运输和脂解。我们预计，控制异位脂类清除的特定分子相互作用的知识将使我们能够设计出促进这一活性的小分子的筛选，长期目标是识别用于治疗肥胖相关脂毒性的先导化合物。

DESCRIPTION (provided by applicant): The storage and mobilization of lipid are fundamental cellular processes, and its dysregulation contributes to numerous diseases including diabetes, atherosclerosis and cardiomyopathy. The central hypothesis of this proposal is that regulated lipolysis involves the orderly trafficking of lipases and co-activators to specialized lipid droplet structures that are organized by specific lipid droplet scaffold proteins. Recent data indicates that protein perilipin A (Plin) is a lipid droplet scaffold protein that coordinates trafficking of lipolytic proteins in adipocytes. The proposed work seeks to build on these results and will characterize the exact temporal ordering of interactions among these lipolytic proteins during PKA stimulated lipolysis in adipocytes in vitro and in situ. Compared to fat cell lipolysis, very little is known about the organization of lipolysis in muscle; however, our preliminary data indicates that Mldp, a novel lipid droplet protein, organizes lipolysis in muscle for intracellular fatty acid oxidation. Using a panel of novel reagents and techniques, we propose to dissect lipolytic trafficking and lipolysis in model myocytes and in true muscle fibers. We anticipate that knowledge of the specific molecular interactions that control ectopic lipid clearance will allow us to devise screens for small molecules that promote this activity, with the long term goal of identifying lead compounds for treatment of obesity-related lipotoxicity.