Lassa virus assembly and release mediated by interplay of viral proteins and cellular factors

该项目的目的是了解拉沙病毒的最终复制步骤，病毒成分的组装和包装，以及病毒颗粒从宿主细胞出芽和释放。拉沙病毒是沙病毒科的一员，由两个螺旋状核糖核衣壳组成，由细胞衍生的含脂包膜包围，包膜内衬基质蛋白，只刺有一种糖蛋白。我们最近发现拉沙病毒Z蛋白是一种病毒基质蛋白。它包含两个被称为晚结构域的四肽基序，参与通常在囊泡运输中起作用的细胞因子的募集。完全表达的重组Z形成病毒样颗粒（vlp）。因此，Z是病毒出芽的主要参与者。我们的目标是：(i)鉴定和表征在不同成熟阶段与拉沙病毒蛋白相互作用的细胞蛋白，（ii） Z和其他病毒蛋白与洗涤剂不溶性糖鞘脂富集膜结构域（DIGs）的相互作用，（iii） Z的寡聚化和晶体结构，以及细胞因子。在结构基础上对病毒成熟的了解将允许设计能够阻断病毒感染的抑制剂，从而可能具有治疗潜力。

The purpose of the project is the understanding of the final Lassa virus replication steps, assembly and packaging of viral components, and budding and release of virus particles from host cells. Lassa virus, a member of Arenaviridae consists of two helical ribonucleocapsids surrounded by a cell-derived, lipid-containing envelope, which is lined with a matrix protein and spiked with only one glycoprotein. We recently identified Lassa virus Z protein as a viral matrix protein. It contains two tetrapeptide motifs known as late domains , which are involved in recruitment of cellular factors which normally function in vesicular transport. Solely expressed recombinant Z forms virus-like particles (VLPs). Thus, Z is a major player of virus budding. Our goals are: (i) identification and characterization of cellular proteins interacting with Lassa viral proteins at different maturation stages, (ii) interaction of Z and other viral proteins with detergent-insoluble glycosphingolipid-enriched membrane domains (DIGs), (iii) oligomerization and crystal structure of Z, together with cellular factors. Insight in virus maturation on structural basis will allow designing inhibitors which are able to block viral infection and thus may have therapeutic potential.