GTP-independent tRNA delivery to the ribosomal P-site by a novel eukaryotic translation factor.

ABSTRACT: During translation, aminoacyl-tRNAs are delivered to the ribosome by specialized GTPases called translation factors. Here, we report the tRNA binding to the P-site of 40 S ribosomes by a novel GTP-independent factor eIF2D isolated from mammalian cells. The binding of tRNA(i)(Met) occurs after the AUG codon finds its position in the P-site of 40 S ribosomes, the situation that takes place during initiation complex formation on the hepatitis C virus internal ribosome entry site or on some other specific RNAs (leaderless mRNA and A-rich mRNAs with relaxed scanning dependence). Its activity in tRNA binding with 40 S subunits does not require the presence of the aminoacyl moiety. Moreover, the factor possesses the unique ability to deliver non-Met (elongator) tRNAs into the P-site of the 40 S s

SUBMITTER: Dmitriev SE 

PROVIDER: S-EPMC2930676 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature