MOLECULAR GENETIC OF MENGOVIRUS TS MUTANTS

我实验室的长期目标是研究阳性- 单链病毒在致病机制的调节方面， 病毒的非致病性菌株向致病性的逆转。 的 本科生和研究生的教育是一个高度优先事项。 在 目前，我的实验室正在研究两种病毒，孟戈病毒和 传染性胃肠炎病毒 门戈病毒属是 伴脑心肌炎的小核糖核酸病毒科病毒群 (EMC)、哥伦比亚SK病毒、泰勒脑炎病毒和毛斯埃尔伯菲尔德病毒。 本项目中的孟戈病毒热稳定株（37 A） O型人红细胞，并导致脑脊髓炎和后肢 小鼠瘫痪。 我们已经准备并部分表征了 通过诱变获得的24个温度敏感（TS）突变体的文库 用亚硝基胍和11个ts突变体进行诱变。 的 该项目的目标是在基因组水平上确定事件如何 突变和回复突变影响热稳定菌株的表型 孟戈病毒 代表五种表型的突变体， 稳定性、血凝、聚合酶产生、致病性和 将从突变体集合中选择温度敏感性，并且 将分离回复突变体。 核苷酸序列的差异 突变体、回复突变体和野生型菌株之间的关系将是 使用重组DNA技术测定。 杂合感染性cDNA或 RNA转录本将用于特异性鉴定和分析 ts突变和回复突变。 将使用定点诱变来 证实并扩展了用杂合感染性cDNA获得的结果 或RNA转录物。 对数据的解释将导致更好的 了解这些病毒特异性表达的调控 功能协调发展的 该项目对理解遗传学有重要意义 调节正链病毒的生理特性。 此外，该项目在开发安全、有效的 疫苗，以及在病毒从组织到组织的传播过程中， 病毒血症

The long term interest of my laboratory is to investigate positive- stranded viruses with respect to the regulation of pathogenesis and reversion of non-pathogenic strains of viruses to pathogenicity. The education of undergraduate and graduate students is a high priority. At present, two viruses are being studied in my laboratory, mengovirus and transmissible gastroenteritis virus. Mengovirus is a member of the Cardiovirus group of the Picornaviridae along with encephalomyocarditis (EMC), Columbia SK, Theiler's encephalitis and Maus Elberfeld viruses. The heat stable strain of mengovirus (37A) in this project agglutinates type O human red blood cells, and causes encephalomyelitis and hind limb paralysis in mice. We have prepared and partially characterized a library of 24 temperature-sensitive (ts) mutants derived by mutagenesis with nitrosoguanidine and 11 ts mutants by acriflavine mutagenesis. The objective of this project is to determine at the genomic level how events of mutation and reversion affect the phenotypes of a heat stable strain of mengovirus. Mutants representative of five phenotypes, heat stability, hemagglutination, polymerase production, pathogenicity and temperature-sensitivity will be selected from the mutant collection, and revertants will be isolated. The differences in nucleotide sequence between the mutants, revertants and the wild-type strain will be determined using recombinant DNA techniques. Hybrid infectious cDNA or RNA transcripts will be utilized to specifically identify and analyze the ts mutations and reversions. Site-directed mutagenesis will be used to confirm and extend the results obtained with the hybrid infectious cDNAs or RNA transcripts. Interpretation of the data will lead to a better understanding of the regulation of expression of these viral-specific functions. This project has significance in understanding genetic regulation of physiological properties of positive-stranded viruses. Further, the project has relevance in the development of safe, effective vaccines, and in the transmission of virus from tissue to tissue during a viremia.