Harty R N, Palese P
Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA.
J Virol. 1995 Aug;69(8):5128-31. doi: 10.1128/JVI.69.8.5128-5131.1995.
A reverse-genetics system employing the chloramphenicol acetyltransferase (CAT) reporter gene has been established previously for Sendai virus. We utilized PCR-directed mutagenesis to introduce nucleotide additions, deletions, and/or substitutions within terminal Sendai virus RNA sequences. The influence of these mutations on replication-transcription of these model Sendai-CAT RNAs was analyzed by assaying CAT activity. Results from these experiments indicate that (i) Sendai-CAT RNAs expressing wild-type levels of CAT activity conform to the Sendai virus rule of six, (ii) apparent exceptions to the rule of six exist in that the 5' terminus of the Sendai-CAT RNA is more tolerant than the 3' terminus of nucleotide additions or deletions, and (iii) the 3' leader region of Sendai-CAT RNA appears to be sensitive not only to mutagenesis (single-nucleotide addition or deletion) but also to changes in its total nucleotide length.
先前已为仙台病毒建立了一种利用氯霉素乙酰转移酶（CAT）报告基因的反向遗传学系统。我们利用聚合酶链反应定向诱变在仙台病毒RNA末端序列中引入核苷酸添加、缺失和/或替换。通过检测CAT活性分析了这些突变对这些模型仙台-CAT RNA复制转录的影响。这些实验结果表明：（i）表达野生型CAT活性水平的仙台-CAT RNA符合仙台病毒的六规则；（ii）六规则存在明显例外，即仙台-CAT RNA的5'末端比3'末端对核苷酸添加或缺失更具耐受性；（iii）仙台-CAT RNA的3'前导区似乎不仅对诱变（单核苷酸添加或缺失）敏感，而且对其总核苷酸长度的变化也敏感。
