Sutter G, Ramsey-Ewing A, Rosales R, Moss B
Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
J Virol. 1994 Jul;68(7):4109-16. doi: 10.1128/JVI.68.7.4109-4116.1994.
Modified vaccinia virus Ankara (MVA), having acquired genomic deletions during passage in chicken embryo fibroblasts, is highly attenuated and unable to productively infect most mammalian cell lines. Multiplication in rabbit kidney-derived RK13 cells, but not other nonpermissive cells, can be restored by insertion of the vaccinia virus K1L gene into the MVA genome. During nonproductive infection of RK13 cells by MVA, transcription of representative viral early genes was revealed by Northern (RNA) blotting, whereas synthesis of an intermediate mRNA and replication of viral DNA could not be detected. Despite the persistence of viral early mRNA for at least several hours, synthesis of virus-induced polypeptides occurred only during the first hour and was followed by abrupt inhibition of all protein synthesis. Transfection of RK13 cells with a eukaryotic expression plasmid that contained the K1L gene allowed MVA infection to proceed to late stages of viral protein synthesis. Moreover, RK13 cell lines that stably expressed the K1L gene were permissive for MVA as well as a K1E deletion mutant of the WR strain of vaccinia virus. This is the first description of the complementation of a poxvirus mutant by cells that stably express a viral gene.
安卡拉痘苗病毒（MVA）在鸡胚成纤维细胞传代过程中发生了基因组缺失，其毒力高度减弱，无法有效感染大多数哺乳动物细胞系。将痘苗病毒K1L基因插入MVA基因组后，可恢复其在兔肾来源的RK13细胞中的增殖能力，但在其他非允许细胞中则不能。在MVA对RK13细胞进行非生产性感染期间，通过Northern（RNA）印迹法可检测到代表性病毒早期基因的转录，但未检测到中间mRNA的合成和病毒DNA的复制。尽管病毒早期mRNA持续存在至少数小时，但病毒诱导的多肽合成仅在最初的一小时内发生，随后所有蛋白质合成突然受到抑制。用含有K1L基因的真核表达质粒转染RK13细胞可使MVA感染进入病毒蛋白质合成的后期阶段。此外，稳定表达K1L基因的RK13细胞系对MVA以及痘苗病毒WR株的K1E缺失突变体均具有允许性。这是首次描述稳定表达病毒基因的细胞对痘病毒突变体的互补作用。
