Shao Junjie, Liang Yuying, Ly Hinh
Department of Veterinary and Biomedical Sciences, University of Minnesota - Twin Cities, 1988 Fitch Ave., 295 AS/VM Bldg, Saint Paul, MN, 55108, USA.
Methods Mol Biol. 2018;1604:217-227. doi: 10.1007/978-1-4939-6981-4_16.
The smallest arenaviral protein is the zinc-finger protein (Z) that belongs to the RING finger protein family. Z serves as a main component required for virus budding from the membrane of the infected cells through self-oligomerization, a process that can be aided by the viral nucleoprotein (NP) to form the viral matrix of progeny virus particles. Z has also been shown to be essential for mediating viral transcriptional repression activity by locking the L polymerase onto the viral promoter in a catalytically inactive state, thus limiting viral replication. The Z protein has also recently been shown to inhibit the type I interferon-induction pathway by directly binding to the intracellular pathogen-sensor proteins RIG-I and MDA5, and thus inhibiting their normal functions. This chapter describes several assays used to examine the important roles of the arenaviral Z protein in mediating virus budding (i.e., either Z self-budding or NP-Z budding activities), viral transcriptional inhibition in a viral minigenome (MG) assay, and type I IFN suppression in an IFN-β promoter-mediated luciferase reporter assay.
最小的沙粒病毒蛋白是锌指蛋白（Z），它属于泛素连接酶E3家族中的指环蛋白家族。Z蛋白是病毒从受感染细胞的膜上出芽所必需的主要成分，通过自身寡聚化实现这一过程，病毒核蛋白（NP）可辅助该过程，以形成子代病毒颗粒的病毒基质。研究还表明，Z蛋白通过将L聚合酶锁定在处于催化失活状态的病毒启动子上，从而介导病毒转录抑制活性，进而限制病毒复制，这一过程至关重要。最近研究还发现，Z蛋白通过直接结合细胞内病原体传感器蛋白RIG-I和MDA5，抑制I型干扰素诱导途径，从而抑制它们的正常功能。本章介绍了几种检测方法，用于研究沙粒病毒Z蛋白在介导病毒出芽（即Z蛋白自身出芽或NP-Z出芽活性）、病毒微型基因组（MG）检测中的病毒转录抑制以及IFN-β启动子介导的荧光素酶报告基因检测中的I型干扰素抑制等方面的重要作用。
