Molecular Biology Of Varicella Zoster Virus Infection

水痘带状疱疹病毒感染的分子生物学

• 批准号: 7964260
• 负责人: Jeffrey Cohen
• 金额: $ 50.25万
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7964260
• 关键词: Acute; Amino Acids; Animals; Binding; Cell Culture Techniques; Cell surface; Cells; Chickenpox; Complex; DNA; Deposition; Enteral; Ganglia; Gene Expression; Glycoproteins; Goals; Growth; Herpes zoster disease; Herpesvirus Type 3; Histones; Human; In Vitro; Infection; Insulinase; Lytic; Mammalian Cell; Molecular Biology; Myxoid cyst; Neurons; Nucleosomes; Phosphorylation Site; Protein Binding; Proteins; Surface; Vaccines; Varicella-Zoster immediate early virus; Virus; Virus Diseases; Virus Latency; Virus Replication; in vivo; latent infection; mutant; protein complex; protein structure; receptor

Primary infection with varicella-zoster virus (VZV) causes chickenpox, and reactivation of the virus from latency results in zoster. We have previously identified a cellular protein, insulin-degrading enzyme (IDE), that interacts with a VZV glycoprotein, gE and functions as a receptor for entry of the virus into cells. VZV gE interacts with glycoprotein I and the two proteins form a complex on the surface of the virus and on virus-infected cells. In 2009, we found that gE was essential for growth of the virus; a VZV mutant deleted for gE could only be grown in cells expressing gE. VZV lacking the IDE binding domain of gE (amino acids 32-71) grew to peak titers nearly equivalent to parental virus; however, the VZV mutant was impaired for cell-to-cell spread and for infectivity with cell-free virus. VZV lacking the IDE binding domain of gE was not impaired for virus maturation or transport to the surface of the cell. VZV deleted for a region of gE (amino acids 163-208) that binds glycoprotein I could not replicate in cell culture unless grown in cells expressing gE. We conclude that the IDE binding domain is important for efficient cell-to-cell spread and infectivity of cell-free virus. VZV immediate-early 63 protein (IE63) is abundantly expressed during both acute infection in cell culture and latent infection in human ganglia. Previously we showed that IE63 is critical for replication (growth) of virus in cell culture and for establishment of latency in animals. The mechanism by which VZV IE63 is important for virus growth in vitro and latent infection in vivo is not known. In 2009 we found that VZV IE63 interacts with human antisilencing function 1 protein (ASF1). ASF1 is a part of a complex of proteins that is important for assembly of nucleosomes, protein structures on DNA that help to regulate expression of genes from the DNA. IE63 bound to ASF1 and colocalized with ASF1 in cells expressing IE63 and in VZV-infected cells. IE63 colocalized with ASF1 in both lytic and latent VZV-infected enteric neurons. ASF1 exists in two forms, ASF1a and ASF1b, in mammalian cells. IE63 preferentially bound to ASF1a, and the amino-terminal 30 amino acids of ASF1a were critical for its interaction with IE63. VZV IE63 amino acids 171 to 208 and putative phosphorylation sites of IE63, both of which are critical for virus replication and latency in animals, were important for the interaction of IE63 with ASF1. ASF1 interacts with histones and other proteins to form nucleosomes on replicating DNA. Histones are proteins that control gene expression by DNA. We found that IE63 increased the binding of ASF1 to histone H3.1 and H3.3, which suggests that IE63 may help to regulate levels of histones in virus-infected cells. Since ASF1 is important for depositing or removing histones during gene expression, the interaction of VZV IE63 with ASF1 may help to regulate virus or cellular gene expression during replication of VZV or during latent infection with VZV.

毒甲菌病毒（VZV）的原发性感染会导致水痘，并从潜伏期中重新激活潜伏期。 我们先前已经鉴定出一种细胞蛋白，即胰岛素降解酶（IDE），该酶与VZV糖蛋白，GE并起作用，作为将病毒渗入细胞的受体。 VZV GE与糖蛋白I I相互作用，两种蛋白质在病毒表面和感染病毒的细胞上形成复合物。 在2009年，我们发现GE对于病毒的生长至关重要。仅在表达GE的细胞中才能生长为GE删除的VZV突变体。 VZV缺乏GE的IDE结合结构域（氨基酸32-71）的峰值滴度几乎等于父母病毒。但是，VZV突变体因细胞到细胞扩散而受损和无细胞病毒感染性。 缺乏GE的IDE结合结构域的VZV不会因病毒成熟或转运到细胞表面而受到损害。 VZV已删除了GE（氨基酸163-208）的区域，该区域结合糖蛋白I在细胞培养中无法复制，除非在表达GE的细胞中生长。我们得出的结论是，IDE结合结构域对于有效的细胞间扩散和无细胞病毒感染性很重要。 VZV在人神经节中细胞培养和潜在感染的急性感染期间，立即至前的63蛋白（IE63）在急性感染期间大量表达。 以前，我们表明IE63对于细胞培养中病毒的复制（生长）至关重要，对动物的潜伏期建立至关重要。 VZV IE63对体外病毒和潜在感染至关重要的机制尚不清楚。 在2009年，我们发现VZV IE63与人类抗分裂函数1蛋白（ASF1）相互作用。 ASF1是蛋白质络合物的一部分，它对于核小体组装，DNA上的蛋白质结构很重要，有助于调节从DNA的基因表达。 IE63与ASF1结合并与表达IE63和VZV感染细胞中的ASF1共定位。 IE63与裂解和潜在VZV感染的肠神经元中的ASF1共定位。 ASF1以两种形式存在于哺乳动物细胞中的ASF1A和ASF1B。 IE63优先与ASF1A结合，ASF1A的氨基末端30氨基酸对于与IE63相互作用至关重要。 VZV IE63氨基酸171至208和IE63的假定磷酸化位点，这对于动物的病毒复制和潜伏期至关重要，对于IE63与ASF1的相互作用很重要。 ASF1与组蛋白和其他蛋白质相互作用，在复制DNA上形成核小体。 组蛋白是通过DNA控制基因表达的蛋白质。 我们发现IE63增加了ASF1与组蛋白H3.1和H3.3的结合，这表明IE63可能有助于调节病毒感染细胞中组蛋白的水平。 由于ASF1对于在基因表达期间沉积或去除组蛋白很重要，因此VZV IE63与ASF1的相互作用可能有助于调节VZV复制期间的病毒或细胞基因表达，或在潜在感染VZV期间。