20S RNA narnavirus defies the antiviral activity of SKI1/XRN1 in Saccharomyces cerevisiae.

ABSTRACT: 20S RNA virus is a persistent positive strand RNA virus found in Saccharomyces cerevisiae. We previously observed that the virus generated in vivo from a launching vector possessed the correct RNA termini without extra sequences. Here we present evidence that the SKI1/XRN1 5'-exonuclease plays a major role in the elimination of the non-viral upstream sequences from the primary transcripts. The virus, once generated, however, is fairly unaffected by overexpression or deletion of SKI1/XRN1. By contrast, the copy number of the L-A double-stranded RNA virus in the same host is greatly increased by the deletion of SKI1/XRN1, and overexpression of the gene cured L-A virus from the cells at a high frequency. 20S RNA virus, unlike L-A virus, has a strong secondary structure at its 5'-end: the firs

SUBMITTER: Esteban R 

PROVIDER: S-EPMC3258869 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature