标题：Poly(riboadenylic acid) preferentially inhibits in vitro translation of cellular mRNAs compared with vaccinia virus mRNAs: possible role in vaccinia virus cytopathology.
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1986
卷号：83
期号：5
页码：1290-1294
DOI：10.1073/pnas.83.5.1290
出版社：The National Academy of Sciences of the United States of America
摘要：Vaccinia virus-induced inhibition of host protein synthesis seems to be mediated by viral transcripts based on their differential inhibition of cellular mRNA translation in a rabbit reticulocyte lysate system. In this study, we demonstrated that the removal of poly(riboadenylic acid) [poly(A)] from the in vitro viral transcripts abolished this inhibition in the same cell-free system. This observation led us to the finding that less than 1 microM poly(A) completely inhibited HeLa cell mRNA translation in the reticulocyte lysate, whereas only 50% inhibition of vaccinia virus mRNA translation was observed at the same concentration. Similar results were also obtained in a wheat germ protein-synthesizing system. This inhibitory effect of poly(A) was totally abrogated by the addition of polydeoxythymidylate. This selective inhibition was highly specific for poly(A) since other homopolymers, including poly(G), poly(C), and poly(dA), were not capable of causing such an inhibition. Poly(U), however, had a moderate selective inhibitory effect. Among the several mRNAs tested, the translation of L-cell, encephalomyocarditis virus, and reovirus RNAs was also sensitive to poly(A). However, vesicular stomatitis virus mRNA translation was strikingly more resistant. These results suggest that poly(A), which is also synthesized by the virion-associated poly(A) polymerase may be involved in vaccinia virus-mediated host cell shutoff.
