Interactions Plante-Virus (IPV), UMR 1090, INRA Bordeaux 2, BP 81, F-33883 Villenave d'Ornon, France.
The translation initiation factors eIF4E and eIF(iso)4E play a key role during virus infection in plants. During mRNA translation, eIF4E provides the cap-binding function and is associated with the protein eIF4G to form the eIF4F complex. Susceptibility analyses of Arabidopsis mutants knocked-out for At-eIF4G genes showed that eIF4G factors are indispensable for potyvirus infection. The colonization pattern by a viral recombinant carrying GFP indicated that eIF4G is involved at a very early infection step. Like eIF4E, eIF4G isoforms are selectively recruited for infection. Moreover, the eIF4G selective involvement parallels eIF4E recruitment. This is the first report of a coordinated and selective recruitment of eIF4E and eIF4G factors, suggesting the whole eIF4F recruitment.