Restriction of KSHV by cellular RNA decay pathways

细胞 RNA 衰变途径对 KSHV 的限制

• 批准号: 10699800
• 负责人: John Karijolich
• 金额: $ 40.03万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10699800
• 关键词: 3' Untranslated Regions; Acquired Immunodeficiency Syndrome; Address; B-Lymphocytes; Biochemical; Biogenesis; Biology; Cell model; Cells; DNA Virus Infections; DNA Viruses; Data; Defense Mechanisms; Development; Disease; Disease Progression; Endoribonucleases; Ensure; Etiology; Gammaherpesvirinae; Gene Expression; Genes; Genetic Transcription; Herpesviridae Infections; Human; Human Herpesvirus 8; Immune response; Kaposi Sarcoma; Knowledge; Life Cycle Stages; Link; Literature; Lymphoma cell; Lymphoproliferative Disorders; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Messenger RNA; Methodology; Molecular; Outcome; Pathway interactions; Plants; Positioning Attribute; Predisposition; Process; Proteins; Quality Control; RNA; RNA Decay; RNA Degradation; RNA Processing; RNA Viruses; Regulation; Reporting; Retroviridae; Ribosomes; Role; Series; Testing; Therapeutic; Transcript; Transcriptional Activation; Translations; Viral; Viral Genes; Viral Genome; Viral Proteins; Virus; Virus Replication; antagonist; antiviral immunity; experimental study; genome wide screen; genome-wide; in vivo; infected B cell; insight; lytic replication; mRNA Decay; member; novel therapeutic intervention; pathogen; primary effusion lymphoma; protein complex; recombinant virus; recruit; response; transcription factor; transcriptome; transcriptomics; viral RNA

Project Summary Kaposi’s sarcoma-associated herpesvirus (KSHV) is a member of the subfamily gammaherpesvirinae and is causally associated with the development of several malignancies including Kaposi’s sarcoma and primary effusion lymphoma (PEL). The virus’ ability to establish latency as well as reactivate are essential for the development of KSHV-associated disease. Despite these requirements for disease progression there are significant gaps in knowledge regarding cell-intrinsic mechanisms that restrict the KSHV lifecycle. While innate restriction is typically thought of in the context of antiviral immune responses, growing evidence suggests that cellular RNA quality control pathways have an antiviral role. Nonsense-mediated RNA decay (NMD) is an evolutionarily conserved RNA decay pathway that facilitates degradation of RNAs on which ribosomes are deemed to terminate translation aberrantly. Emerging evidence has pointed to a role for NMD in antiviral restriction with a prominent role limiting replication of positive-stranded RNA viruses, however, a role for NMD in DNA virus restriction, such as KSHV, was unknown. We recently reported the discovery that NMD is a cell- intrinsic restriction mechanism for DNA viruses and demonstrated that it imposes a significant restriction on the KSHV lifecycle in PEL cells. Our data demonstrate that NMD-dependent restriction is linked both to the regulation of the unfolded protein response (UPR) as well as targeted degradation of the main KSHV transcription factor, RTA. Building upon these observations our central hypothesis is that NMD restricts KSHV reactivation by targeting key viral mRNAs as well as cellular transcripts in pathways important for viral gene expression and that the virus antagonizes NMD through viral-encoded mechanisms. To test this hypothesis, we propose an integrated series of experiments aimed at determining the interactions between NMD and KSHV. In Aim 1, we will investigate how NMD-dependent regulation of the UPR pathway regulates the KSHV lifecycle. In Aim 2, we will investigate a class of KSHV mRNAs that escape NMD despite harboring sequence features that should render them NMD-susceptible. In Aim 3, we will determine the mechanism by which KSHV-encoded proteins inhibit NMD. Completion of these studies is expected to determine how NMD restricts the KSHV lifecycle as well as the mechanisms the virus employs to antagonize it. These will represent fundamental new insights into how DNA virus infection is regulated by cell-intrinsic mechanisms and can be harnessed for the development of new therapeutic strategies.

项目摘要 卡波西肉瘤相关疱疹病毒（KSHV）是γ疱疹病毒亚科的成员， 与几种恶性肿瘤的发生有因果关系，包括卡波西肉瘤和原发性 渗出性淋巴瘤（PEL）。病毒建立潜伏期和重新激活的能力对于 KSHV相关疾病的发展。尽管有这些疾病进展的要求， 关于限制KSHV生命周期的细胞内在机制的知识存在重大差距。虽然先天 限制通常被认为是在抗病毒免疫反应的背景下，越来越多的证据表明， 细胞RNA质量控制途径具有抗病毒作用。无义介导的RNA衰变（NMD）是一种 进化上保守的RNA衰变途径，促进核糖体所依赖的RNA的降解。 视为异常终止翻译。新出现的证据表明NMD在抗病毒方面的作用 限制具有显著的作用，限制正链RNA病毒的复制，然而，NMD在 DNA病毒限制，如KSHV，未知。我们最近报道发现NMD是一个细胞， DNA病毒的内在限制机制，并证明它对DNA病毒的 PEL细胞中的KSHV生命周期。我们的数据表明，依赖NMD的限制与调节 未折叠蛋白反应（UPR）以及主要KSHV转录因子的靶向降解， RTA。基于这些观察，我们的中心假设是，NMD通过以下方式限制KSHV的再激活： 靶向病毒基因表达重要途径中的关键病毒mRNA以及细胞转录物， 该病毒通过病毒编码机制对抗NMD。为了验证这一假设，我们提出了一个 一系列旨在确定NMD和KSHV之间相互作用的综合实验。目标1： 将研究NMD依赖的UPR途径调节KSHV的生命周期。在目标2中， 将研究一类KSHV mRNAs，尽管它们具有应该 使他们对NMD敏感。在目标3中，我们将确定KSHV编码的蛋白质 抑制NMD。这些研究的完成预计将确定国家导弹防御系统如何限制KSHV的生命周期以及 作为病毒对抗它的机制。这些将代表对病毒如何 DNA病毒感染受细胞内在机制调节，可用于开发新的 治疗策略