In vivo interaction between Tobacco mosaic virus RNA-dependent RNA polymerase and host translation elongation factor 1A.

Several host translation elongation factors have been suggested to play essential roles in the replication and translation of viral RNAs in plants, animals and bacteria. Here, we show the interaction between eukaryotic translation elongation factor 1A (eEF1A) and Tobacco mosaic virus (TMV) RNA-dependent RNA polymerase (RdRp) in vivo by immunoprecipitation. The tobacco eEF1A interacted not only with 3'-untranslated region (3'-UTR) of TMV RNA but also directly with RdRp without mediation by the 3'-UTR. The methyltransferase domain of TMV RdRp was indicated to be responsible for the interaction with eEF1A in vitro and in yeast. These results suggest that eEF1A is a component of the virus replication complex of TMV.