Eukaryotic translation initiation factor 4GI and p97 promote cellular internal ribosome entry sequence-driven translation.

ABSTRACT: Numerous cellular mRNAs encoding proteins critical during cell stress, apoptosis, and the cell cycle seem to be translated by means of internal ribosome entry sequences (IRES) when cap-dependent translation is compromised. The underlying molecular mechanisms are largely unknown. Using a HeLa-based cell-free translation system that mirrors the function of cellular IRESs in vitro, we recently demonstrated that translation from the c-myc IRES continues after proteolytic cleavage of eukaryotic translation initiation factor (eIF) 4G. To address the role of eIF4G in cellular IRES-driven translation directly, we immunodepleted eIF4GI from the HeLa cell translation extracts. After efficient depletion of eIF4GI (>90%), both cap-dependent and c-myc IRES-dependent translations are diminished to resid

SUBMITTER: Hundsdoerfer P 

PROVIDER: S-EPMC1224658 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature