STUDIES WITH SYNTHETIC NEURAMINIDASE SUBSTRATES

我们将继续研究流感病毒的分子流行病学 使用生物化学技术。 将进行一项研究， 早期H1N1病毒株（1950-57）的进化变化， 在1950年类似H1N1病毒株中观察到， 1977年人口。 遗传变异也将在以下方面进行研究 马1型流感病毒（H7 N7）。 这些病毒似乎经历了更慢的 比人类流感病毒的抗原性变化。 此外，我们将 分析新抗原的基因组成和抗原特性 流感病毒的“漂移”和抗原性“转变”变异体， 未来 我们已经开发了一种方便的测定琥珀抑制tRNA的方法 在高等真核细胞中的活性。 本试验基于 NS 1多肽及其Su+ tRNA介导的通读的定量 病毒感染后的产品。 计划将这一方法推广到 测量蛋白石和赭石抑制基因， 高等真核细胞中的无义抑制tRNA活性。 与 含有Su+ tRNA的基因工程细胞的可用性， 也可以分离流感病毒的无义突变体， 它们用于研究流感病毒的结构/功能关系 基因. 我们还计划应用抑制系统来产生突变体， 通过SV 40表达的克隆流感病毒基因的蛋白质 向量。 这种方法将使我们能够系统地改变具体的 氨基酸，以努力识别这些氨基酸 对蛋白质的功能至关重要的酸。

We will continue to study the molecular epidemiology of influenze viruses using biochemical techniques. A study will be undertaken to contrast the evolutionary changes in the earlier H1N1 strains (1950-57) with those observed in the 1950-like H1N1 strains which were reintroduced into the population in 1977. Genetic variation will also be studied with respect to equine 1 influenza viruses (H7N7). These viruses appear to undergo slower antigenic change than human influenza viruses. In addition, we will analyze the genetic composition and antigenic properties of new antigenic "drift" and antigenic "shift" variants of influenza viruses isolated in the future. We have developed a convenient assay to measure amber suppressor tRNA activity in higher eukaryotic cells. This assay is based on the quantitation of the NS1 polypeptide and its Su+ tRNA mediated readthrough product after virus infection. It is planned to extend this method for the measurement of opal and ochre suppressor tRNAs and to search for natural nonsense suppressor tRNA activities in higher eukaryotic cells. With the availability of genetically engineered cells containing Su+ tRNAs it should also be possible to isolate nonsense mutants of influenza virus and to use them for studying the structure/function relationship of influenza viral genes. We also plan to apply the suppressor systems to generate mutant proteins of cloned influenza virus genes which are expressed via SV40 vectors. This approach will allow us to systematically change specific amino acids in a single viral protein in an effort to identify those amino acids which are crucial for the function of the protein.