Analysis of lipolytic trafficking in adipocytes

描述（由申请人提供）：脂质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。该建议的中心假设是，受调节的脂肪分解涉及到由特定的脂滴支架蛋白组织的专门的脂滴结构中脂酶和共激活剂的有序运输。最近的数据表明，蛋白periilipin A （Plin）是一种脂滴支架蛋白，在脂肪细胞中协调脂溶蛋白的运输。提出的工作旨在建立在这些结果的基础上，并将描述在体外和原位脂肪细胞中PKA刺激的脂肪分解过程中这些脂溶蛋白之间相互作用的确切时间顺序。与脂肪细胞的脂肪分解相比，我们对肌肉中脂肪分解的组织机制知之甚少；然而，我们的初步数据表明，Mldp，一种新型脂滴蛋白，在肌肉中组织脂肪分解以进行细胞内脂肪酸氧化。使用一组新的试剂和技术，我们建议解剖脂肪分解运输和脂肪分解在模型肌细胞和真正的肌纤维。我们预计，控制异位脂质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种活性的小分子筛选，并以确定治疗肥胖相关脂肪毒性的先导化合物为长期目标。

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.