Construction and analysis of additional adenovirus substitution mutants confirm the complementation of VAI RNA function by two small RNAs encoded by Epstein-Barr virus.
Adenovirus VAI RNA is essential for the efficient initiation of translation of viral mRNAs at late times after infection. Recently, by constructing an adenovirus type 5 substitution mutant, we showed that the Epstein-Barr virus encoded two small RNAs complemented for the VAI RNA function in the adenovirus type 5 lytic growth (Bhat and Thimmappaya, Proc. Natl. Acad. Sci. USA 80:4789-4793, 1983). This observation was based on our inability to propagate an adenovirus type 5 mutant lacking functional VAI and VAII genes. Subsequently, it was found that this mutant was viable and able to grow to a low titer. Therefore, we examined the complementation of the VAI RNA function by the Epstein-Barr virus-encoded RNAs by constructing additional adenovirus type 5 substitution mutants containing multiple copies of the Epstein-Barr virus-encoded RNA genes in nonessential early transcriptional region III. The new substitution mutants synthesized viral polypeptides at late times at levels comparable to those observed in wild type-infected cells. Our results convincingly demonstrated that the two Epstein-Barr virus-encoded RNAs can efficiently complement for the VAI RNA-mediated translational defect in adenovirus-infected cells.
D000260:Adenoviruses, Human / Q000235:genetics*; D005786:Gene Expression Regulation; D005816:Genetic Complementation Test; D004854:Herpesvirus 4, Human / Q000235:genetics*; D008970:Molecular Weight; D009154:Mutation; D012320:RNA Polymerase III / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D014764:Viral Proteins / Q000235:genetics; D014779:Virus Replication
D012367:RNA, Viral; D014764:Viral Proteins; D012320:RNA Polymerase III