Schoelz James E, Leisner Scott
Division of Plant Sciences, University of Missouri, Columbia, MO, United States.
Department of Biological Sciences, University of Toledo, Toledo, OH, United States.
Front Plant Sci. 2017 Oct 30;8:1832. doi: 10.3389/fpls.2017.01832. eCollection 2017.
Similar to cells, viruses often compartmentalize specific functions such as genome replication or particle assembly. Viral compartments may contain host organelle membranes or they may be mainly composed of viral proteins. These compartments are often termed: inclusion bodies (IBs), viroplasms or viral factories. The same virus may form more than one type of IB, each with different functions, as illustrated by the plant pararetrovirus, (CaMV). CaMV forms two distinct types of IBs in infected plant cells, those composed mainly of the viral proteins P2 (which are responsible for transmission of CaMV by insect vectors) and P6 (required for viral intra-and inter-cellular infection), respectively. P6 IBs are the major focus of this review. Much of our understanding of the formation and function of P6 IBs comes from the analyses of their major protein component, P6. Over time, the interactions and functions of P6 have been gradually elucidated. Coupled with new technologies, such as fluorescence microscopy with fluorophore-tagged viral proteins, these data complement earlier work and provide a clearer picture of P6 IB formation. As the activities and interactions of the viral proteins have gradually been determined, the functions of P6 IBs have become clearer. This review integrates the current state of knowledge on the formation and function of P6 IBs to produce a coherent model for the activities mediated by these sophisticated virus-manufacturing machines.
与细胞类似，病毒通常会将特定功能进行区室化，例如基因组复制或病毒粒子组装。病毒区室可能包含宿主细胞器膜，也可能主要由病毒蛋白组成。这些区室通常被称为：包涵体（IBs）、病毒质或病毒工厂。同一病毒可能形成不止一种类型的包涵体，每种包涵体具有不同功能，植物副逆转录病毒花椰菜花叶病毒（CaMV）就是一个例子。CaMV在受感染的植物细胞中形成两种不同类型的包涵体，分别主要由病毒蛋白P2（负责CaMV通过昆虫载体传播）和P6（病毒细胞内和细胞间感染所必需）组成。P6包涵体是本综述的主要关注点。我们对P6包涵体形成和功能的许多理解来自于对其主要蛋白质成分P6的分析。随着时间的推移，P6的相互作用和功能逐渐得到阐明。结合新技术，如使用荧光团标记病毒蛋白的荧光显微镜，这些数据补充了早期的研究工作，并更清晰地呈现了P6包涵体的形成过程。随着病毒蛋白的活性和相互作用逐渐被确定，P6包涵体的功能也变得更加清晰。本综述整合了关于P6包涵体形成和功能的当前知识状态，以构建一个由这些复杂的病毒制造机器介导的活动的连贯模型。
