Control of translation by VSV

通过 VSV 控制翻译

基本信息

批准号：
6680824
负责人：
DOUGLAS S. LYLES
金额：
$ 28.78万
依托单位：
WAKE FOREST UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-09-29 至 2005-09-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): The control of translation plays a critical role in the pathogenesis of many viruses. The inhibition of host protein synthesis is important for suppression of the host antiviral response, while the selective translation of viral mRNAs is important for virus propagation in the host. Translational control by vesicular stomatitis virus (VSV), the prototype rhabdovirus, is one of the best-studied examples among the nonsegmented, negative-stranded RNA viruses. Previous experiments have made it clear that VSV uses novel mechanisms to control translation that are distinct from those of other well-studied RNA viruses, such as picornaviruses and influenza viruses. The goal of this project is to determine these mechanisms by which VSV inhibits host protein synthesis and promotes viral protein synthesis. Previous work has shown that the translation factor elF2alpha is inactivated in VSV-infected cells as a result of phosphorylation by protein kinase R. However, we have shown that the cap-binding elF4F complex is also inactivated in VSV-infected cells. Aim 1 is to determine how elF4F is inactivated, and the relative contribution of elF4F versus elF2alpha inactivation in the inhibition of host protein synthesis in VSV-infected cells. Aim 2 is to determine the viral components responsible for inducing the inhibition of host protein synthesis. These studies will use new recombinant viruses to map the genes of VSV mutants that are either more effective or less effective than wild-type VSV in the inhibition of host translation. Aim 3 is to determine the basis of resistance of viral mRNAs to the inhibition of translation. These experiments will use chimeric mRNAs containing viral or host 5' and 3' untranslated regions to test for the presence of cis-acting sequences that enhance translation of viral mRNAs. We will also test recombinant viruses that express these chimeric mRNAs to determine whether mRNA synthesis by the viral transcriptase confers the resistance to the inhibition of translation. Upon completion of these experiments, we will have important new information about how viruses suppress the antiviral response in the host, and how they promote expression of their own gene products. The results of these experiments will be novel, because the mechanisms used by VSV differ substantially from those of other well-studied prototype viruses. Finally, it is very likely that there are host mRNAs that use mechanisms similar to those of VSV mRNAs to enhance their translation under conditions such as stress. Thus we expect to gain new insight into regulation of cellular translation under other conditions where the activities of translation initiation factors are inhibited.

描述（由申请人提供）：翻译控制在许多病毒的发病机制中起着关键作用。抑制宿主蛋白质合成对于抑制宿主抗病毒反应很重要，而病毒 mRNA 的选择性翻译对于病毒在宿主中的传播很重要。水泡性口炎病毒（VSV）（弹状病毒的原型）的翻译控制是非节段负链 RNA 病毒中研究得最好的例子之一。之前的实验已经表明，VSV 使用新颖的机制来控制翻译，这些机制不同于其他经过充分研究的 RNA 病毒（例如小RNA病毒和流感病毒）。该项目的目标是确定 VSV 抑制宿主蛋白质合成和促进病毒蛋白质合成的机制。先前的工作表明，由于蛋白激酶 R 的磷酸化，翻译因子 elF2alpha 在 VSV 感染的细胞中失活。然而，我们已经证明，帽子结合的 elF4F 复合物在 VSV 感染的细胞中也失活。目的 1 是确定 eF4F 如何失活，以及 eF4F 与 eF2α 失活在抑制 VSV 感染细胞中宿主蛋白合成方面的相对贡献。目标 2 是确定负责诱导宿主蛋白质合成抑制的病毒成分。这些研究将使用新的重组病毒来绘制 VSV 突变体的基因图谱，这些突变体在抑制宿主翻译方面比野生型 VSV 更有效或更无效。目的3是确定病毒mRNA抵抗翻译抑制的基础。这些实验将使用含有病毒或宿主 5' 和 3' 非翻译区的嵌合 mRNA 来测试增强病毒 mRNA 翻译的顺式作用序列的存在。我们还将测试表达这些嵌合 mRNA 的重组病毒，以确定病毒转录酶合成的 mRNA 是否具有对翻译抑制的抵抗力。完成这些实验后，我们将获得有关病毒如何抑制宿主抗病毒反应以及它们如何促进自身基因产物表达的重要新信息。这些实验的结果将是新颖的，因为 VSV 使用的机制与其他经过充分研究的原型病毒的机制有很大不同。最后，很可能存在宿主 mRNA 使用与 VSV mRNA 类似的机制来增强其在应激等条件下的翻译。因此，我们期望获得对翻译起始因子活性受到抑制的其他条件下细胞翻译调节的新见解。