Role of Lipids in Hepatitis C Virus Maturation

 描述（由申请人提供）：慢性丙型肝炎病毒感染影响全球约1.7亿人，并构成纤维化、脂肪变性和肝细胞癌（HCC）的重要风险因素。丙型肝炎病毒感染是肝移植的主要指标。在这里，我们提出的特点的作用，脂质在病毒形态发生主要集中在成熟和分泌从感染的肝细胞。在以前的资助中，我们已经确定并表征了几种脂质和脂质相互作用蛋白在影响HCV分泌中的作用。 HCV通过高尔基体网络的成熟/分泌被认为与极低密度脂蛋白（VLDL）组装和分泌相关。VLDL转运发生在专门的VLDL转运囊泡（VTV）中。我们建议使用已建立的分离VTV的生化分离程序来表征HCV相关VTV在高尔基体网络中的运输。一个新的描述在体外出芽测定后高尔基体VTV运输将进行检查。HCV感染细胞中VTV的特性对了解HCV分泌过程具有重要意义。我们还建议，以确定功能的重要性，影响高尔基体运输的大型货物，如VTV在HCV成熟的因素。在这种情况下，几种蛋白质，包括磷脂酰肌醇-4磷酸（PI 4P）相互作用蛋白Arfaptin显示影响大型货物的trans-Golgi网络将其特征在于其在HCV-VTV运输的作用。这些研究将揭示对HCV成熟、分泌和排出机制的独特见解，并将作为其他RNA病毒的模型。本研究的结果将为影响HCV分泌途径的细胞靶点的治疗设计开辟新的途径。

 DESCRIPTION (provided by applicant): Chronic Hepatitis C virus infections affect about 170 million people worldwide and constitute a significant risk factor for fibrosis, steatosis and hepatocellular carcinoma (HCC). HCV infections are a major indicator for liver transplantation. Here, we propose to characterize the role of lipids in virion morphogenesis mostly focusing on maturation and secretion from infected hepatocytes. In the previous grant we had identified and characterized the role of several lipids and lipid interacting proteins in affecting HCV secretion. HCV maturation/secretions through the Golgi network is believed to occur in association with very low-density lipoprotein (VLDL) assembly and secretion. VLDL transport occurs in specialized VLDL transport vesicles (VTVs). We propose to characterize the transport of HCV-associated VTVs across the Golgi network using the established biochemical fractionation procedures for isolating VTVs. A newly described in vitro budding assay for the post- Golgi VTV transport will be examined. Characterization of VTVs in HCV infected cells containing HCV virions components is of fundamental importance to the understating the process of HCV secretion. We also propose to determine the functional importance of factors that affect Golgi transport of large cargos such as VTVs in HCV maturation. In this context, several proteins including a phosphatidylinosito-4 phosphate (PI4P)- interacting protein Arfaptin shown to affect large cargos in the trans-Golgi network will be characterized for their role in HCV-VTV transport. These studies will reveal unique insight into the mechanisms of HCV maturation, secretion and egress and will serve as a model for other RNA viruses. The results of this study will open new avenues for therapeutic design of cellular targets affecting the HCV secretory pathway.