Role of Nuclear Lamina in the epigenetic regulation of Epstein-Barr Virus Infection

项目摘要 EB病毒（EBV）是一种人γ疱疹病毒，其感染约95%的人， 群体，并作为染色质相关的多拷贝附加体潜伏在记忆B细胞中。EBV感染 与包括不同类型的淋巴瘤和胃癌在内的几种病理有因果关系。 EBV相关疾病的这种异质性可能反映了不同的基因表达程序， 病毒适应不同的细胞类型和宿主细胞条件。我们和其他人已经证明， 修饰有助于建立和维持这些替代的病毒基因表达程序， 延迟。我们确定了细胞因子如CTCF影响EBV表观基因组;然而，我们仍然缺乏一个完整的表观基因组。 对调节EBV潜伏期的机制有全面的了解。 与不同的核亚室，包括核纤层的相互作用，有助于 调节潜在DNA区域的表达。核纤层是一种蛋白质网络， 内核膜。除了为细胞核提供结构支持外，核板层还 对核周边染色质的正确组织至关重要。因此，基因定位于 核周边常常表达不佳。由于CTCF已知与核 核纤层，这支持了核纤层有助于调节EBV基因表达的观点。 然而，核纤层作为EBV表观基因组的关键调节因子的作用还有待探索。 我们在这里报告，为第一次，核纤层和EBV之间的潜在相互作用 染色体，它可以调节病毒染色质。目前还不清楚EB病毒是否定位于 核外围以及这种关联如何影响病毒基因组功能。我们的项目旨在填补这一空白 通过探索核纤层-EBV相互作用对EBV基因组的表观遗传调控的作用。我们 假设核纤层有助于EBV基因表达的表观遗传控制， 潜伏期，CTCF在EBV-核纤层相互作用中起作用。在这里，我们将使用基因组 在EBV突变体和不同EBV阳性B细胞系中的方法：1）鉴定哪些EBV基因组区域是 核纤层相关区域的染色质状态;以及 CTCF在介导核纤层蛋白和EBV基因组之间的相互作用中的作用;以及2）确定核纤层蛋白和EBV基因组之间的相互作用。 纤层结合对EBV基因表达和EBV染色质结构影响。我们的研究将提供新的 深入了解调节EBV潜伏基因表达的机制。考虑到核纤层在 其他病毒的感染周期，我们的提议可能具有重要的生物学和翻译意义 更广泛的病毒学领域。

Project Summary Epstein-Barr virus (EBV) is a human gammaherpes virus that infects approximately 95% of the population and remains latent in memory B cells as a chromatin-associated multicopy episome. EBV infection is causally associated with several pathologies including different types of lymphomas and gastric carcinoma. This heterogeneity in EBV-associated diseases may reflect the different gene expression programs that the virus adopts in different cell types and host-cell conditions. We and others have shown that epigenetic modifications contribute to establish and maintain these alternative viral gene expression programs during latency. We identified that cellular factors such as CTCF affect the EBV epigenome; however, we still lack a complete understanding of mechanisms regulating EBV latency. Interactions with different nuclear sub-compartments, including the nuclear lamina, contribute to regulating the expression of underlying DNA regions. The nuclear lamina is a protein meshwork that underlies the inner nuclear membrane. In addition to providing structural support for the nucleus, the nuclear lamina is crucial for the proper organization of chromatin at the nuclear periphery. As such, genes that are localized to the nuclear periphery are frequently poorly expressed. Since CTCF is known to associate with the nuclear lamina, this supports the idea that the nuclear lamina contributes to the regulation of EBV gene expression. However, the role of the nuclear lamina as key regulator of the EBV epigenome has yet to be explored. We report here, for the first time, a potential interaction between the nuclear lamina and the EBV chromosome, which may regulate viral chromatin. At the present it remains unknown if EBV localizes at the nuclear periphery and how this association can affect viral genome functions. Our project aims to fill this gap by exploring the role of nuclear lamina-EBV interaction on the epigenetic regulation of the EBV genome. We hypothesize that the nuclear lamina contributes to the epigenetic control of EBV gene expression during latency, and that CTCF plays a role in the EBV-nuclear lamina interaction. Here we will use a genomic approach in EBV mutants and different EBV positive B-cell lines to: 1) identify which EBV genomic regions are associated with the nuclear lamina; the chromatin state of these lamin-associated regions; and the role of CTCF in mediating the interaction between lamins and the EBV genome; and 2) determine the role of nuclear lamina association on EBV gene expression and EBV chromatin organization. Our studies will provide new insight into the mechanism regulating EBV latent gene expression. Considering the role of nuclear lamina in the infection cycles of other viruses our proposal can have significant biological and translational implications for the broader virology field.