Translation without eIF2 promoted by poliovirus 2A protease.

ABSTRACT: Poliovirus RNA utilizes eIF2 for the initiation of translation in cell free systems. Remarkably, we now describe that poliovirus translation takes place at late times of infection when eIF2 is inactivated by phosphorylation. By contrast, translation directed by poliovirus RNA is blocked when eIF2 is inactivated at earlier times. Thus, poliovirus RNA translation exhibits a dual mechanism for the initiation of protein synthesis as regards to the requirement for eIF2. Analysis of individual poliovirus non-structural proteins indicates that the presence of 2A(pro) alone is sufficient to provide eIF2 independence for IRES-driven translation. This effect is not observed with a 2A(pro) variant unable to cleave eIF4G. The level of 2A(pro) synthesized in culture cells is crucial for obtaining eIF2

SUBMITTER: Redondo N 

PROVIDER: S-EPMC3189197 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature