RNA REPAIR AND RECOMBINATION--AN ALPHAVIRUS MODEL

RNA 修复和重组——阿尔法病毒模型

• 批准号: 6180539
• 负责人: Ramasamy Raju
• 金额: $ 17.37万
• 依托单位: MEHARRY MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 2002-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6180539
• 关键词: Sindbis virus; genetic recombination; replicon; synthetic nucleic acid; tissue /cell culture; transfection; virus RNA; virus genetics

DESCRIPTION: RNA replicons function as genomes for a large number of animal, human, plant and insect viruses. Despite the increased vulnerability of RNA for nucleolytic breakdown, RNA viruses continue to overpopulate the virus world. High mutation rates and RNA-RNA recombination are believed to play a critical role in RNA genome evolution, persistence and pathogenesis. Arboviruses, the largest group of animal RNA viruses, because of their wide tissue and host specificity, are forced to evolve faster than other viruses. Sindbis virus (SIN), the subject of this proposal, is a mosquito-transmitted human alphavirus. Many human alphaviruses including Western equine encephalitis (WEE) have evolved by genetic recombination between SIN and Eastern equine encephalitis virus (EEE). Furthermore, the emerging use of alphavirus RNA replicons in gene therapeutics and vaccines warrants a detailed understanding of the biology of RNA replicons. The long term goal of this project is to understand the mechanism of alphavirus RNA repair and recombination in infected host cells. Infectious cDNA clones of SIN are engineered to express a battery of replicative and nonreplicative RNA precursors. Both mammalian and mosquito cells are transfected with these engineered RNAs, and the ability of the viral polymerase to repair and generate infectious virus from these host cells are characterized. There are three specific aims: (1) To study the role of nucleotide homology between template RNAs in homologous recombination; (2) To study the role of template-template interaction, RNA structures and cryptic promoter-like elements in the generation of nonhomologous SIN recombinants; and (3) To identify the amino acid changes in virus polymerase proteins which render SIN RNAs recombination-defective.

描述：RNA 复制子充当大量基因组 动物、人类、植物和昆虫病毒。 尽管增加了 由于RNA易被溶核分解，RNA病毒继续 病毒世界人口过多。 高突变率和 RNA-RNA 重组 被认为在RNA基因组进化、持久性中发挥着关键作用 及发病机制。 虫媒病毒是最大的动物 RNA 病毒类群， 由于它们广泛的组织和宿主特异性，被迫进化 比其他病毒更快。 辛德比斯病毒 (SIN)，本文的主题 建议，是一种通过蚊子传播的人类甲病毒。 许多人类 包括西方马脑炎 (WEE) 在内的甲病毒是由 SIN 与东部马脑炎病毒的基因重组 （EEE）。 此外，甲病毒RNA复制子在基因中的新兴应用 治疗方法和疫苗需要对生物学有详细的了解 RNA复制子。 该项目的长期目标是了解 受感染宿主细胞中甲病毒RNA修复和重组的机制。 SIN 的感染性 cDNA 克隆经过改造可表达一系列 复制性和非复制性 RNA 前体。 哺乳动物和蚊子 细胞被这些工程化的 RNA 转染，并且 病毒聚合酶从这些宿主中修复并产生感染性病毒 细胞被表征。 具体目标有以下三点：（1）研究 模板RNA之间核苷酸同源性在同源性中的作用 重组； (2) 研究模板-模板相互作用、RNA的作用 结构和神秘启动子样元件的产生 非同源 SIN 重组体； (3) 鉴定氨基酸变化 病毒聚合酶蛋白导致 SIN RNA 重组缺陷。