The Processing of eIF4GI by Human Rhinovirus Type 2 2Apro: Relationship to Self-Cleavage and Role of Zinc

摘要: The 2A proteinase (2Apro) of human rhinoviruses (HRVs) is a cysteine protease containing structurally important zinc ion. In the viral polyprotein, enzyme cleaves between C terminus VP1 and its own N terminus. 2Apro also processes two isoforms cellular protein, eukaryotic initiation factor 4G (eIF4G). We have shown that mature HRV2 2Apro, when translated in vitro rabbit reticulocyte lysates, efficiently eIF4GI, although was not immediately active upon synthesis. Here, we examine relationship self-processing eIF4GI cleavage. onset both reactions first occurred at least 10 min after protein Furthermore, prevented by specific mutation VP1-2Apro precursor essentially unable to cleave implying prerequisite for synthesized presence potent chelator inactive; however, addition excess zinc, rapidly gained activity. Finally, culture medium can protect HeLa cells from HRV infection.