Translation initiation factor IF- 2 <p>Initiation factor 2 (IF-2) is one of the three factors required for the initiation of protein biosynthesis in bacteria. 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.</p> <p>The function of IF-2 in facilitating the proper binding of initiator methionyl-tRNA to the ribosomal P site appears to be universally conserved, with an IF-2 homologue (aIF-2) present in archaea bacteria [<cite idref="PUB00035262"/>] <taxon tax_id="2320">Methanopyrus kandleri</taxon>.</p>