Control of Translation in Herpesvirus infected Cells

疱疹病毒感染细胞中翻译的控制

• 批准号: 6886110
• 负责人: Ian J Mohr
• 金额: $ 32.11万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6886110
• 关键词: SDS polyacrylamide gel electrophoresis; biological signal transduction; cytotoxicity; endoplasmic reticulum; flow cytometry; genetic translation; herpes simplex virus 1; host organism interaction; immunoprecipitation; kinase inhibitor; laboratory rabbit; mass spectrometry; molecular dynamics; phosphorylation; physiologic stressor; posttranslational modifications; protein biosynthesis; protein folding; protein kinase; protein protein interaction; translation factor; virus RNA; virus cytopathogenic effect; virus infection mechanism; virus protein

DESCRIPTION (provided by applicant): The capacity of eukaryotic cells to respond to numerous forms of stress, ranging from thermal intolerance or nutrient deprivation to viral infection, involves, in part, their ability to regulate the activity of elF2, a critical translation initiation factor. Upon phosphorylation on it's alpha subunit by one of four known elF2alpha kinases, elF2 is inactivated and translation is inhibited. The overall long - term objective of this project is to understand how elF2alpha phosphorylation is regulated in response to stress generated by viral infection. In infected cells, the appropriation and redirection of many cellular functions coupled with the rapid accumulation of viral gene products induces cellular stress and activates host defenses. Copious quantities of double stranded (ds)RNA produced in virus infected cells activates the cellular elF2alpha kinase PKR, while the synthesis of viral glycoproteins increases the load on the endoplasmic reticulum, exceeding its capacity to correctly fold and process ER client proteins. This latter condition triggers the unfolded protein response (UPR) and the ensuing phosphorylation of elF2alpha arrests translation. In this proposal, we investigate viral strategies that prevent host defenses from inactivating the translation factor elF2. Our studies focus on herpes simplex virus-1, a neurotrophic herpesvirus whose productive replication is responsible for a spectrum of diseases, ranging from epithelial sores, severe ocular disease and life threatening encephalitis in immunocompetent hosts to disseminated disease in neonates and immunocompromised individuals. Both the gamma(1)34.5 and Us11 gene products are known to regulate elF2alpha phosphorylation. While the gamma(1)34.5 gene product recruits a cellular phosphatase to dephosphorylate elF2alpha, Us11 prevents activation of the cellular elF2alpha kinase PKR via an unknown mechanism. Furthermore, HSV-1 expresses a previously uncharacterized function, distinct from the polypeptide products of the Us11and gamma(1)34.5 genes, that confers resistance to ER stress. We will (i) evaluate the effects of HSV-1 infection on ER stress transducers; (ii) identify the gene product (s) responsible for preventing elF2alpha phosphorylation in response to effectors that stimulate the UPR; and (iii) investigate the molecular mechanisms by which Us11 prevents PKR activation.

描述（由申请人提供）：真核细胞对多种形式的压力做出反应的能力，从热不耐受或营养剥夺到病毒感染，部分涉及它们调节ELF2活性的能力，ELF2是关键的翻译起始因子。在通过四种已知ELF2Alpha激酶之一对其α亚基的磷酸化后，ELF2被灭活并抑制了翻译。该项目的整体长期目标是了解如何根据病毒感染产生的应力来调节Elf2alpha磷酸化。在受感染的细胞中，许多细胞功能的分配和重定向以及病毒基因产物的快速积累会诱导细胞应激并激活宿主防御。在病毒感染细胞中产生的大量双链（DS）RNA激活了细胞ELF2Alpha激酶PKR，而病毒糖蛋白的合成增加了内质网的载荷，超过其正确折叠和处理ER客户端蛋白的能力。后一种条件触发了展开的蛋白质反应（UPR）和随之而来的Elf2alpha抑制磷酸化。 在此提案中，我们研究了防止宿主防御能力灭活翻译因子ELF2的病毒策略。我们的研究专注于单纯疱疹病毒-1，一种神经营养性疱疹病毒，其富有生产力的复制负责疾病谱系，从上皮疮，严重的眼部疾病和危及生命的脑炎脑炎在不合情上的宿主到新生儿和免疫能力成像中的疾病中疾病的宿主。已知伽马（1）34.5和US11基因产物都调节ELF2Alpha磷酸化。而伽马（1）34.5基因产物募集了细胞磷酸酶以去磷酸化的Elf2alpha，而US11则通过未知机制阻止了细胞ELF2Alpha激酶PKR的激活。此外，HSV-1表达了先前未表征的功能，该功能与US11和Gamma（1）34.5基因的多肽产物不同，该基因赋予了对ER应激的抗性。我们将（i）评估HSV-1感染对ER应力传感器的影响； （ii）确定负责防止ELF2Alpha磷酸化的基因产物，以响应刺激UPR的效应子； （iii）研究US11阻止PKR激活的分子机制。