Structural highlights
Function
IF2P_HUMAN Plays a role in translation initiation (PubMed:10659855, PubMed:35732735). Ribosome-dependent GTPase that promotes the joining of the 60S ribosomal subunit to the pre-initiation complex to form the 80S initiation complex with the initiator methionine-tRNA in the P-site base paired to the start codon (PubMed:10659855, PubMed:35732735). Together with eIF1A (EIF1AX), actively orients the initiator methionine-tRNA in a conformation that allows 60S ribosomal subunit joining to form the 80S initiation complex (PubMed:12569173, PubMed:35732735). Is released after formation of the 80S initiation complex (PubMed:35732735). Its GTPase activity is not essential for ribosomal subunits joining, but GTP hydrolysis is needed for eIF1A (EIF1AX) ejection quickly followed by EIF5B release to form elongation-competent ribosomes (PubMed:10659855, PubMed:35732735). In contrast to its procaryotic homolog, does not promote recruitment of Met-rRNA to the small ribosomal subunit (PubMed:10659855).[1] [2] [3]
References
- ↑ Pestova TV, Lomakin IB, Lee JH, Choi SK, Dever TE, Hellen CU. The joining of ribosomal subunits in eukaryotes requires eIF5B. Nature. 2000 Jan 20;403(6767):332-5. PMID:10659855 doi:10.1038/35002118
- ↑ Marintchev A, Kolupaeva VG, Pestova TV, Wagner G. Mapping the binding interface between human eukaryotic initiation factors 1A and 5B: a new interaction between old partners. Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):1535-40. PMID:12569173 doi:10.1073/pnas.0437845100
- ↑ Lapointe CP, Grosely R, Sokabe M, Alvarado C, Wang J, Montabana E, Villa N, Shin BS, Dever TE, Fraser CS, Fernández IS, Puglisi JD. eIF5B and eIF1A reorient initiator tRNA to allow ribosomal subunit joining. Nature. 2022 Jul;607(7917):185-190. PMID:35732735 doi:10.1038/s41586-022-04858-z