Metabolic regulation of Epstein-Barr Virus-infected tonsillar B cells by EBNA-LP

EBNA-LP 对 Epstein-Barr 病毒感染的扁桃体 B 细胞的代谢调节

• 批准号: 10581497
• 负责人: Jana Cable
• 金额: $ 4.09万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10581497
• 关键词: Adult; Alanine; Antigens; B-Lymphocytes; Binding; Binding Proteins; Biological Assay; Cell Maturation; Cell Proliferation; Cell Survival; Cells; Cellular Metabolic Process; Chromatin; Chromatin Remodeling Factor; Co-Immunoprecipitations; Collagen; Complex; Data; Disease; EP300 gene; Electron Microscopy; Enzymes; Epstein-Barr Virus Infections; Epstein-Barr Virus Nuclear Antigens; Epstein-Barr Virus latency; Epstein-Barr Virus-Related Malignant Neoplasm; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Genus Hippocampus; Glucose; Goals; Growth; Herpesviridae; Higher Order Chromatin Structure; Human Herpesvirus 4; Hydroxyproline; Immune; Immune response; Immunofluorescence Immunologic; In Vitro; Individual; Infection; Infectious Mononucleosis; Leucine; Lymphoid Tissue; Lymphoma; Mediating; Membrane; Memory; Memory B-Lymphocyte; Metabolic; Metabolic Activation; Metabolism; Modeling; Modification; Molecular; Mutation; Nuclear; Nuclear Protein; Oral; Oral cavity; Organelles; Outcome; Oxidative Phosphorylation; Oxygen Consumption; Patients; Peptides; Phase; Post-Translational Protein Processing; Procollagen-Proline Dioxygenase; Proline; Protein Family; Proteins; Regulation; Role; Saliva; Site; Structure of germinal center of lymph node; T-Lymphocyte; Tonsil; Transcription Coactivator; Up-Regulation; Viral Proteins; Virus; Virus Diseases; YY1 Transcription Factor; cell growth; cell growth regulation; insight; latent infection; lymphoblastoid cell line; mutant; new therapeutic target; novel; oral cavity epithelium; promoter; protein oligomer; recruit; stable cell line; therapeutic target; transcription factor; transcriptome sequencing; transmission process; tumorigenesis

Epstein-Barr Virus (EBV) infects over 90% of adults worldwide and initially establishes infection in the oral cavity, including tonsillar B cells. Upon infecting naïve B cells, EBV expresses viral proteins including EBV Nuclear Antigens (EBNAs), transcriptional co-activators that promote B cell maturation and establish latently infected memory B cell reservoirs. EBV-associated malignancies include infectious mononucleosis, and, in immune compromised hosts, tumorigenesis including lymphomas. Recently, it has been appreciated that EBV induces metabolic changes upon infection. Our lab has discovered that EBV upregulates oxidative phosphorylation (OXPHOS) in order to promote cell proliferation and avoid arrest. Similarly, naïve B cells also require increased OXPHOS upon activation by antigen in order to undergo germinal center remodeling and produce memory B cells. Therefore, the ultimate goal of this proposal is to elucidate the molecular mechanisms by which EBV alters OXPHOS, which will enhance our understanding of EBV requirements for latency, and the role of metabolism in B cell maturation. Intriguingly, the viral protein EBNA-Leader Protein (EBNA-LP) is required for infection of naïve B cells, but not memory B cells – although the essential role of EBNA-LP is not well characterized. Our preliminary data suggests the viral protein EBNA-Leader Protein (EBNA-LP) may be essential in upregulation OXPHOS through transcriptional co-activation of metabolic genes. Our data suggests that EBNA-LP binds transcription factors that regulate expression of OXPHOS-related genes including NRF1, ERRα, and YY1 and then recruits chromatin remodeling factors such as P300. This mechanism of transcriptional co-activation mimics the PGC family of proteins, which uses leucine-rich motifs to bind the same OXPHOS transcription factors and recruit remodelers. Our preliminary data supports this model in that EBNA-LP contains multiple leucine-rich motifs, which may be required for binding these transcription factors. Additionally, EBNA-LP forms nuclear bodies, or membraneless organelles, that may be essential for EBNA-LP to regulate transcription, including OXPHOS genes. Our preliminary data suggests that EBNA-LP contains a post-translational modification, hydroxyproline, which promotes protein oligomerization and higher order structures in modified substrates such as collagen. Therefore, I propose that hydroxyprolination of EBNA-LP is required to form EBNA-LP nuclear bodies and co-activate transcription. My overall hypothesis is that EBNA-LP induces transcription of OXPHOS genes by using leucine-rich motifs to mimic the cellular PGC family of proteins, and through forming nuclear bodies upon hydroxyprolination. In Aim 1, I will assess the role of leucine-rich motifs in mediating transcription of OXPHOS genes and upregulation of cellular OXPHOS in tonsillar B cells. In Aim 2, I will determine the role of hydroxyprolination of EBNA-LP in formation of nuclear bodies and metabolic regulation in infected cells. These studies will elucidate novel mechanisms by which a viral protein regulates transcription and B cell metabolism and will provide insight towards understanding EBV-related malignancies.

EB 病毒 (EBV) 感染全世界 90% 以上的成年人，最初在口腔中建立感染， 包括扁桃体 B 细胞。感染幼稚 B 细胞后，EBV 表达病毒蛋白，包括 EBV 核。 抗原 (EBNA)、促进 B 细胞成熟和建立潜伏感染的转录共激活剂 记忆 B 细胞储存库与 EB 病毒相关的恶性肿瘤包括传染性单核细胞增多症和免疫性疾病。 宿主受损、包括淋巴瘤在内的肿瘤发生最近已被认识到 EBV 会诱发。 我们的实验室发现 EBV 上调氧化磷酸化。 (OXPHOS) 为了促进细胞增殖并避免停滞，类似地，幼稚 B 细胞也需要增加。 OXPHOS 被抗原激活后进行生发中心重塑并产生记忆 B 因此，该提案的最终目标是阐明 EBV 改变的分子机制。 OXPHOS，这将增强我们对 EBV 潜伏期要求以及代谢在 有趣的是，病毒蛋白 EBNA-Leader Protein (EBNA-LP) 是幼稚病毒感染所必需的。 B 细胞，但不是记忆 B 细胞——尽管 EBNA-LP 的重要作用尚不清楚。 初步数据表明病毒蛋白 EBNA-Leader Protein (EBNA-LP) 可能在上调中至关重要 我们的数据表明 EBNA-LP 通过代谢基因的转录共激活来结合 OXPHOS。 调节 OXPHOS 相关基因表达的转录因子，包括 NRF1、ERRα 和 YY1 以及 然后招募染色质重塑因子，例如 P300，模仿这种转录共激活机制。 PGC 蛋白家族，使用富含亮氨酸的基序结合相同的 OXPHOS 转录因子， 我们的初步数据支持这一模型，因为 EBNA-LP 含有多种富含亮氨酸。 此外，EBNA-LP 形成核体，可能需要这些基序。 或无膜细胞器，可能对 EBNA-LP 调节转录至关重要，包括 OXPHOS 我们的初步数据表明 EBNA-LP 含有翻译后修饰，羟脯氨酸， 它促进胶原蛋白等改性基质中的蛋白质寡聚化和高级结构。 因此，我认为 EBNA-LP 的羟基脯氨酸化是形成 EBNA-LP 核体并共同激活转录所必需的。我的总体假设是 EBNA-LP 通过使用诱导 OXPHOS 基因的转录。 富含亮氨酸的基序来模拟细胞 PGC 蛋白家族，并通过在其上形成核体 在目标 1 中，我将评估富含亮氨酸的基序在介导 OXPHOS 转录中的作用。 基因和扁桃体 B 细胞中细胞 OXPHOS 的上调 在目标 2 中，我将确定 OXPHOS 的作用。 EBNA-LP 的羟脯氨酸化在感染细胞核体形成和代谢调节中的作用。 研究将阐明病毒蛋白调节转录和 B 细胞代谢的新机制 并将提供了解 EBV 相关恶性肿瘤的见解。