KSHV latent infection replication

KSHV潜伏感染复制

• 批准号: 9215662
• 负责人: Kenneth M Kaye
• 金额: $ 44.38万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9215662
• 关键词: Acquired Immunodeficiency Syndrome; Africa South of the Sahara; Architecture; Binding; Binding Sites; Biology; Blood group antigen S; Cell Cycle; Cell Nucleus; Cell Survival; Cells; Closure by clamp; Complex; Crystallization; DNA; DNA biosynthesis; DNA-Directed DNA Polymerase; Daughter; Development; Dominant-Negative Mutation; Epidemic; Episome; Epstein-Barr Virus Infections; Etiology; Genome; HIV; Herpesviridae; Herpesviridae Infections; Human; Human Herpesvirus 4; Human Herpesvirus 8; Immune; Kaposi Sarcoma; Latent virus infection phase; Link; Malignant Neoplasms; Mediating; Multicentric Angiofollicular Lymphoid Hyperplasia; Oral cavity; Organ; Outcome; Persons; Plasmids; Polymerase; Process; Proliferating; Proteins; Reagent; Recruitment Activity; Resolution; Roentgen Rays; Role; Saliva; Site; Structure; Terminal Repeat Sequences; Testing; Therapeutic; Validation; Viral; Viral Genome; Virus; Virus Diseases; Virus Latency; Virus Replication; Visceral; Work; antigen binding; cell type; co-infection; daughter cell; experimental study; inhibitor/antagonist; latency-associated nuclear antigen; latent infection; molecular imaging; neoplastic cell; prevent; primary effusion lymphoma; public health relevance; segregation; single molecule; small molecule inhibitor; targeted treatment; therapeutic target; tumor; viral DNA

 DESCRIPTION (provided by applicant): Kaposi's sarcoma (KS)-associated herpesvirus (KSHV or HHV8) is the causative agent of KS, primary effusion lymphoma (PEL) and multicentric Castleman's disease. KSHV is spread person to person through saliva. KSHV tumors occur primarily in AIDS and other immune compromised states. There are no available specific therapies for these tumors. KS is the leading AIDS malignancy and is epidemic in sub Saharan Africa where coinfection with HIV is common. KS often involves the oral cavity and visceral organs. KSHV latently infects tumor cells. During latent infection viral genomes persist as multiple copy, extrachromosomal, circular episomes (plasmids). To persist in proliferating cells, episomes must replicate with each cell cycle and efficiently segregate to daughter nuclei. The latency-associated nuclear antigen (LANA) mediates KSHV episome persistence and is strictly required for viral latency and KSHV survival in proliferating cells. Episome maintanence is comprised of two components: replication of KSHV DNA, and segregation of replicated episomes to daughter cell nuclei. LANA is responsible for both these functions. To replicate KSHV DNA, LANA binds viral terminal repeat (TR) DNA. Since no KSHV DNA replication proteins are expressed during latent infection, LANA is responsible for recruiting host cell replication machinery. Although LANA interacts with several cell replication factors, little is known regarding the underlying mechanisms through which LANA mediates replication. We recently found that LANA recruits the DNA polymerase clamp loader to mediate efficient replication and viral persistence. Loss of this recruitment greatly inhibited LANA's ability to mediate DNA replication and resulted in loss of virus infection. These findings suggested that clamp loading is a rate-limiting step in DNA replication that is incompatible with virus survival. LANA enhancement of clamp loading enables KSHV replication, persistence, and survival. The overarching hypothesis of this application is that LANA's recruitment of the clamp loader is a fundamental component of KSHV replication biology that is an ideal target for potential therapeutic inhibition. Experiments will test this hypothesis. Work will assess the mechanism by which LANA enhances clamp loading. Experiments will investigate the architecture of the LANA-clamp loader complex. In addition, experiments will target the LANA-clamp loader complex for inhibition. The expected outcome of this work is a detailed understanding of the mechanism through which LANA acts on the clamp loader and validation of this interaction as a potential therapeutic target for KSHV malignancy.

 描述（由申请人提供）：卡波西肉瘤（KS）相关疱疹病毒（KSHV 或 HHV8）是 KS、原发性渗出性淋巴瘤（PEL）和多中心 KSHV 的病原体，KSHV 肿瘤主要通过唾液在人与人之间传播。在艾滋病和其他免疫受损的国家，这些肿瘤没有可用的特异性治疗方法，KS 是主要的艾滋病恶性肿瘤，并且在亚裔中流行。在撒哈拉非洲地区，HIV 合并感染很常见。KSHV 潜伏感染肿瘤细胞，在潜伏感染过程中，病毒基因组以多拷贝、染色体外、环状附加体（质粒）形式存在于增殖细胞中。必须在每个细胞周期中复制并有效地分离到子细胞核。潜伏期相关核抗原 (LANA) 介导 KSHV 游离体持久性，并且是病毒潜伏期和子代细胞核所必需的。 KSHV 在增殖细胞中的存活由两个部分组成：KSHV DNA 的复制和复制的附加体与子细胞核的分离负责这两种功能。为了复制 KSHV DNA，LANA 结合病毒末端重复序列 (TR)。 DNA。由于在潜伏感染期间不表达 KSHV DNA 复制蛋白，LANA 负责招募宿主细胞复制机制。尽管 LANA 与多种细胞复制因子相互作用，但人们对 LANA 的潜在机制知之甚少。我们最近发现 LANA 招募 DNA 聚合酶钳装载机来介导有效的复制和病毒持久性，这种招募的丧失极大地抑制了 LANA 介导 DNA 复制的能力，并导致病毒感染的丧失。 DNA 复制中与病毒存活不相容的限速步骤 LANA 钳加载的增强能够实现 KSHV 的复制、持久性和存活 该应用的首要假设是 LANA 的钳加载器的募集是一个基本因素。 KSHV 复制生物学的组成部分，是潜在治疗抑制的理想靶标。实验将评估 LANA 增强钳负载的机制。此外，实验将研究 LANA-钳装载复合物的结构。这项工作的预期结果是详细了解 LANA 对钳装载机的作用机制，并验证这种相互作用作为 KSHV 恶性肿瘤的潜在治疗靶点。