IN VITRO TRANSLATION AS A PROBE FOR THE MECHANISM OF POL

一些核苷酸的变化对神经毒力有显著的影响 脊髓灰质炎病毒基因组的潜力。最重要的站点，类型 3，位于病毒基因组的n个非翻译区，影响 病毒式翻译。最近对一种成功的体外试验的描述 使用添加的脊髓灰质炎病毒RNA的HeLa细胞翻译系统已经提供 一种潜在的方法来调查和进一步定义 通过定义和比较差异来减弱基因组变化 野生型和萨宾减毒基因组之间。蛋白质合成的应用 抑制剂为一种新的反馈调节机制提供了证据 将脊髓灰质炎病毒RNA合成与核糖体活性水平联系起来。 与脊髓灰质炎病毒5‘端非翻译区相关的初步证据 与这种调节机制相关的基因组提示 这种衰减反映了这种病毒调控的变化 机制。目前的研究进一步定义了体内的反应和 体外聚合酶/翻译偶联检测方法的建立 再现在活体中观察到的事件。 PI负责对脊髓灰质炎病毒疫苗解放军和IND进行审查 文件。我们对分子的理解取得了重大进展 脊髓灰质炎病毒疫苗的神经注意机制将由 关于有限数量的核苷酸在离散状态下如何变化的研究 脊髓灰质炎病毒基因组中的位置会导致 神经毒性表型。这样的知识可以用来产生改进的， 稳定的减毒病毒株，复原率降低， 从而减少了与疫苗相关的脊髓灰质炎病例。此外， 我们的研究可以导致基于分子的神经毒力测试 预测新的脊髓灰质炎病毒疫苗株的安全性，并从根本上 了解病毒如何利用细胞的调节机制 促进病毒复制的过程。

A few nucleotide changes have a significant effect on the neurovirulent potential of the poliovirus genome. The most significant site, for Type 3, is located in a n untranslated region of the viral genome and affects viral translation. The recent description of a successful in vitro translation system from HeLa cells using added poliovirus RNA has offered a potential method to investigate and further define the role of the attenuating genome changes by defining and comparing the differences between wild type and Sabin attenuated genomes. Use of protein synthesis inhibitors provided evidence for a novel feedback regulatory mechanism linking poliovirus RNA synthesis to the level of ribosomal activity. Preliminary evidence linking the 5' untranslated region of the poliovirus genome associated with attenuation to this regulatory mechanismsuggests that attenuation reflects an alteration in this viral regulatory mechanism. Current research further defines the response in vivo and the development of an in vitro coupled polymerase/translation assay capable of reproducing events observed in vivo. The PI is responsible for the review of polio virus vaccine PLA and IND documents. A significant advance in our understanding of the molecular mechanisms for neuroattentuation of poliovirus vaccines would be served by the study of how a limited number of nucleotide changes at discrete positions in the poliovirus genome result in attenuation of the neurovirulent phenotype. Such knowledge can be used to produce improved, stabile attenuated viral strains, with reduced rates of reversion, resulting in fewer cases of vaccine related poliomyelitis. Furthermore, our studies can lead to molecularly based neurovirulence testing to predict the safety of new poliovirus vaccine strains, and to a fundamental understanding of how viruses employ regulatory mechanisms of cellular processes to promote viral replication.