IF-2 is a translation initiator in each of the three main phylogenetic domains (Eukaryotes  Bacteria  and Archaea ). IF2 interacts with formylmethionine-tRNA, GTP, IF1, IF3 and both ribosomal subunits . Through these interactions, IF2 promotes the binding of the initiator tRNA to the A site in the smaller ribosomal subunit and catalyses the hydrolysis of GTP following initiation-complex formation .
Initiation factor 2 (IF-2) is one of the three factors required for the initiation of protein biosynthesis in bacteria [PUBMED:15755955]. IF-2 promotes the GTP-dependent binding of the initiator tRNA to the small subunit of the ribosome. IF-2 is a protein of about 70 to 95 kDa that contains a central GTP-binding domain flanked by a highly variable N-terminal domain and a more conserved C-terminal domain. Some members of this group undergo protein self splicing that involves a post-translational excision of the intein followed by peptide ligation.
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