Synergistic roles of eukaryotic translation elongation factors 1B? and 1A in stimulation of tombusvirus minus-strand synthesis.

ABSTRACT: Host factors are recruited into viral replicase complexes to aid replication of plus-strand RNA viruses. In this paper, we show that deletion of eukaryotic translation elongation factor 1Bgamma (eEF1B?) reduces Tomato bushy stunt virus (TBSV) replication in yeast host. Also, knock down of eEF1B? level in plant host decreases TBSV accumulation. eEF1B? binds to the viral RNA and is one of the resident host proteins in the tombusvirus replicase complex. Additional in vitro assays with whole cell extracts prepared from yeast strains lacking eEF1B? demonstrated its role in minus-strand synthesis by opening of the structured 3' end of the viral RNA and reducing the possibility of re-utilization of (+)-strand templates for repeated (-)-strand synthesis within the replicase. We also show that eEF1B? plays a synergistic role with eukaryotic translation elongation factor 1A in tombusvirus replication, possibly via stimulation of the proper positioning of the viral RNA-dependent RNA polymerase over the promoter region in the viral RNA template.These roles for translation factors during TBSV replication are separate from their canonical roles in host and viral protein translation.

SUBMITTER: Sasvari Z 

PROVIDER: S-EPMC3240602 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature