CMV Control of Host Membrane Trafficking

项目摘要/摘要 病毒侵占宿主膜运输以促进病毒复制。虽然这是一个关键的控制点 对于病毒感染，病毒如何劫持宿主蛋白和促进感染的途径是不完全的 明白了。病毒介导的膜运输变化最能被理解为建立复制 RNA病毒的隔间和组装部位。然而，人们对DNA病毒是如何 影响宿主体内的膜重塑。人巨细胞病毒(CMV)是一种复杂的DNA病毒，是一种 疱疹病毒家族的成员，在宿主中建立终生感染。在感染期间，CMV 导致膜转运的改变，导致多囊泡体的生物发生增加 (MVBS)，对发出信号和胞吐或降解货物很重要的细胞器。在感染期间，MVB 变得充满病毒颗粒和致密小体(病毒被膜蛋白的小泡)。这些机制由 哪些CMV控制宿主膜运输途径，特别是MVB的生物发生 明白了。因此，确定病毒蛋白和宿主靶点对于膜的调节很重要 贩运是一个对宿主和病毒生物学有重要影响的重要目标。我们已经确认了两个 CMV蛋白，pUL135和pUL136，调节MVB的生物发生。缺乏UL135或的重组病毒 UL136基因在MVB的生物发生和病毒载体的掺入过程中发生了深刻的变化。 与这些表型一致，我们已经确定了pUL135和pUL136的宿主相互作用蛋白 对于膜运输和MVB生物发生至关重要的蛋白质。两种病毒蛋白的发现 它们的宿主相互作用使我们能够确定CMV调节细胞膜的机制 贩卖和MVB生物发生。我们假设UL135和UL136主机相互作用共同选择主机 调节病毒复制的膜运输和MVB途径。提出了三个要解决的目标 这个假说。我们将定义UL135和UL136与亚细胞膜隔间的联系 和宿主蛋白。在目标2中，我们将定义宿主相互作用对病毒复制的意义， 膜运输，以及将货物纳入MVB，以了解CMV的机制基础- 调解对宿主贩运的控制。最后，我们将研究UL135和UL136及其宿主的作用 在调节MVB生物发生中的相互作用的伙伴，并确定这一调节如何影响病毒输出。我们的 研究将确定CMV所针对的病毒与宿主的相互作用和传播途径及其对 感染。此外，我们预计我们的发现将揭示许多病毒使用的共同策略 操纵贩运途径。

PROJECT SUMMARY / ABSTRACT Viruses commandeer host membrane trafficking to promote viral replication. While this is a critical control point for virus infection, how viruses hijack host proteins and pathways to promote infection is incompletely understood. Viral-mediated alterations in membrane trafficking are best understood for building replication compartments and sites of assembly for RNA viruses. However, much less is known about how DNA viruses influence membrane remodeling in the host. Human cytomegalovirus (CMV) is a complex DNA virus and a member of the herpesvirus family that establishes a lifelong infection in the host. During infection, CMV induces alterations in membrane trafficking that results in increased biogenesis of multivesicular bodies (MVBs), organelles important for signaling and exocytosis or degradation of cargo. During infection, MVBs become loaded with virus particles and dense bodies (vesicles of viral tegument protein). The mechanisms by which CMV controls host membrane trafficking pathways, and particularly MVB biogenesis, are not understood. Therefore, defining the viral proteins and host targets important for the regulation of membrane trafficking is an important goal with important implications for host and virus biology. We have identified two CMV proteins, pUL135 and pUL136, which regulate MVB biogenesis. Recombinant viruses lacking UL135 or UL136 genes exhibit profound alterations in MVB biogenesis and the incorporation of viral cargo into MVB. Consistent with these phenotypes, we have identified host interacting proteins for both pUL135 and pUL136 proteins that are important for membrane trafficking and MVB biogenesis. The discovery of two viral proteins and their host interactions strongly position us to define the mechanisms by which CMV modulates membrane trafficking and MVB biogenesis. We hypothesize that UL135- and UL136-host interactions co-opt host membrane trafficking and MVB pathways to modulate virus replication. Three aims are proposed to address this hypothesis. We will define the association of UL135 and UL136 with subcellular membrane compartments and host proteins in Aim 1. In Aim 2, we will define the significance of host interactions to virus replication, membrane trafficking, and incorporation of cargo into MVBs to understand the mechanistic basis of CMV- mediated control of host trafficking. Finally, we will investigate the role of UL135 and UL136 and their host interacting partners in regulating MVB biogenesis and determine how this regulation impacts viral egress. Our studies will define the virus-host interactions and trafficking pathways targeted by CMV and their significance to infection. Furthermore, we anticipate that our findings will uncover common strategies used by many viruses to manipulate trafficking pathways.