Summary

Name EIF2S3
Full Name Eukaryotic translation initiation factor 2 subunit 3
Synonyms Eukaryotic translation initiation factor 2 subunit gamma X, eIF-2-gamma X, eIF-2gX | EIF2G
Primary ID P41091
Links - -
Type protein
Relations 6
Function As a subunit of eukaryotic initiation factor 2 (eIF-2), involved in the early steps of protein synthesis. In the presence of GTP, eIF-2 forms a ternary complex with initiator tRNA Met-tRNAi and then recruits the 40S ribosomal complex and initiation factors eIF-1, eIF-1A and eIF-3 to form the 43S pre-initiation complex (43S PIC), a step that determines the rate of protein translation. The 43S PIC binds to mRNA and scans downstream to the initiation codon, where it forms a 48S initiation complex by codon-anticodon base pairing. This leads to the displacement of eIF-1 to allow GTPase-activating protein (GAP) eIF-5-mediated hydrolysis of eIF2-bound GTP. Hydrolysis of GTP and release of Pi, which makes GTP hydrolysis irreversible, causes the release of the eIF-2-GDP binary complex from the 40S subunit, an event that is essential for the subsequent joining of the 60S ribosomal subunit to form an elongation-competent 80S ribosome. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must be exchanged with GTP by way of a reaction catalyzed by GDP-GTP exchange factor (GEF) eIF-2B (By similarity). Along with its paralog on chromosome Y, may contribute to spermatogenesis up to the round spermatid stage (By similarity).

Viewer

Relations

Regulator Mechanism target score
+ up-regulates activity img/direct-activation.png guanine nucleotide exchange factor EIF2S3 0.679
Publications: 1 Organism: Homo Sapiens
+ form complex img/form-complex.png binding Ternary_GTP_eIF2_tRNA_complex 0.937
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png guanine nucleotide exchange factor EIF2S3 0.684
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png guanine nucleotide exchange factor EIF2S3 0.68
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png guanine nucleotide exchange factor EIF2S3 0.723
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png guanine nucleotide exchange factor EIF2S3 0.723
Publications: 1 Organism: Homo Sapiens