The viral RNA plays multiple roles during replication of RNA viruses, serving as a template for complementary RNA synthesis and facilitating the assembly of the viral replicase complex. These roles are coordinated by cis-acting regulatory elements, such as promoters and replication enhancers (REN). To test if these RNA elements can be used by related viral RNA-dependent RNA polymerases (RdRp), we compared the potential stimulatory effects of homologous and heterologous REN elements on complementary RNA synthesis and template-switching by the tombus- (Cucumber necrosis virus, CNV), carmovirus (Turnip crinkle virus, TCV) and hepatitis C virus (HCV) RdRps in vitro. The CNV RdRp selectively utilized its cognate REN, while discriminating against the heterologous TCV REN. On the contrary, RNA synthesis by the TCV RdRp was stimulated by the TCV REN and the heterologous tombusvirus REN with comparable efficiency. The heterologous REN elements also promoted in vitro template-switching by the TCV and HCV RdRps. Based on these observations, we propose that REN elements could facilitate intervirus recombination and postrecombinational amplification of new recombinant viruses.
|Number of pages||15|
|State||Published - Oct 10 2005|
Bibliographical noteFunding Information:
The authors thank Drs. Judit Pogany and Saulius Serva. This work was supported by NIH-NIAID (AI055866-01) and the University of Kentucky.
- In vitro RNA synthesis
- Interviral recombination
- RNA promoter
- RNA replication enhancer
ASJC Scopus subject areas