Rota P A, Bloom A E, Vanchiere J A, Bellini W J
Respiratory and Enterovirus Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30333.
Virology. 1994 Feb;198(2):724-30. doi: 10.1006/viro.1994.1086.
To characterize the genetic properties of currently circulating strains of wild-type measles viruses, we constructed and sequenced cDNA clones of the nucleoprotein (N) and matrix (M) genes of wild-type strains isolated between 1958 and 1989. The N and M genes of wild-type isolates from the prevaccine era (before 1964) were highly related to each other and to the N and M genes of a currently used measles vaccine strain, Moraten. The N and M genes of these viruses differed by no more than 0.5% at the nucleotide level. In contrast, the N and M genes of wild-type viruses isolated between 1977 and 1989 showed genetic drift, with the greatest amount of drift occurring in the viruses isolated from recent cases in the United States. Overall, the M genes were slightly more conserved at the nucleotide level (2.6% nucleotide, 3.3% amino acid) than the N genes (4.8% nucleotide, 3.4% amino acid). Alignment of the predicted protein sequences of the N genes revealed two regions of amino acid heterogeneity. The evolutionary patterns for the N and M genes suggested that the wild-type viruses isolated in the United States in 1989 were more related to wild-type viruses isolated in the United Kingdom between 1983 and 1988 than to viruses isolated in the United States in 1983.
为了描述当前流行的野生型麻疹病毒株的遗传特性，我们构建并测序了1958年至1989年间分离的野生型株的核蛋白（N）和基质（M）基因的cDNA克隆。疫苗接种前时代（1964年以前）野生型分离株的N和M基因彼此高度相关，并且与当前使用的麻疹疫苗株莫拉汀的N和M基因高度相关。这些病毒的N和M基因在核苷酸水平上的差异不超过0.5%。相比之下，1977年至1989年间分离的野生型病毒的N和M基因显示出遗传漂变，其中最大量的漂变发生在美国近期病例分离的病毒中。总体而言，M基因在核苷酸水平上（核苷酸2.6%，氨基酸3.3%）比N基因（核苷酸4.8%，氨基酸3.4%）稍微更保守一些。N基因预测蛋白序列的比对揭示了两个氨基酸异质性区域。N和M基因的进化模式表明，1989年在美国分离的野生型病毒与1983年至1988年间在英国分离的野生型病毒的相关性比与1983年在美国分离的病毒的相关性更高。
