Protein: Eukaryotic translation initiation factor 2 subunit 3, X-linked (EC 3.6.5.3) (Eukaryotic translation initiation factor 2 subunit gamma, X-linked) (eIF2-gamma X) (Q9Z0N1)
Organism: Mus musculus (Mouse)
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.
Subcellular location: Cytoplasm, cytosol {ECO:0000250|UniProtKB:Q09130}.
Sequence: MAGGEGGVTLGQPHLSRQDLATLDVTKLTPLSHEVISRQATINIGTIGHVAHGKSTVVKAISGVHTVRFKNELERNITIKLGYANAKIYKLDDPSCPRPECYRSCGSSTPDEFPTDIPGTKGNFKLVRHVSFVDCPGHDILMATMLNGAAVMDAALLLIAGNESCPQPQTSEHLAAIEIMKLKHILILQNKIDLVKESQAKEQYEQILAFVQGTVAEGAPIIPISAQLKYNIEVVCEYIVKKIPVPPRDFTSEPRLIVIRSFDVNKPGCEVDDLKGGVAGGSILKGVLKVGQEIEVRPGIVSKDSEGKLMCKPIFSKIVSLFAEHNDLQYAAPGGLIGVGTKIDPTLCRADRMVGQVLGAVGALPEIFTELEISYFLLRRLLGVRTEGDKKAAKVQKLSKNEVLMVNIGSLSTGGRVSAVKADLGKIVLTNPVCTEVGEKIALSRRVEKHWRLIGWGQIRRGVTIKPTVDDD
InterPro domains: - IPR004161: Translation elongation factor EFTu-like, domain 2 (domain) [276-358]
- IPR044127: Initiation factor eIF2 gamma, domain 2 (domain) [249-362]
- IPR050543: Eukaryotic Initiation Factor 2 Gamma Subunit (family) [14-468]
- IPR000795: Translational (tr)-type GTP-binding domain (domain) [39-248]
- IPR009001: Translation elongation factor EF1A/initiation factor IF2gamma, C-terminal (homologous_superfamily) [364-460]
- IPR044128: Initiation factor eIF2 gamma, GTP-binding domain (domain) [42-248]
- IPR027417: P-loop containing nucleoside triphosphate hydrolase (homologous_superfamily) [33-252]
- IPR009000: Translation protein, beta-barrel domain superfamily (homologous_superfamily) [248-362]
- IPR015256: Initiation factor eIF2 gamma, C-terminal (domain) [365-459]
Interaction partners: - Eukaryotic translation initiation factor 2 subunit 2
- Eukaryotic translation initiation factor 2 subunit 1
- Ubiquitin-like protein FUBI
- Eukaryotic translation initiation factor 3 subunit E
- Eukaryotic translation initiation factor 3 subunit B
- Eukaryotic translation initiation factor 3 subunit C
- Translation initiation factor eIF2B subunit alpha
- Eukaryotic translation initiation factor 3 subunit G
- Eukaryotic translation initiation factor 3 subunit I
- Translation initiation factor eIF2B subunit epsilon
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0045182 (translation regulator activity), GO:0005488 (binding), GO:0097159 (organic cyclic compound binding), GO:0090079 (translation regulator activity, nucleic acid binding), GO:1901363 (heterocyclic compound binding), GO:0003676 (nucleic acid binding), GO:0008135 (translation factor activity, RNA binding), GO:0003743 (translation initiation factor activity)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0009058 (biosynthetic process), GO:0044238 (primary metabolic process), GO:0044237 (cellular metabolic process), GO:0071704 (organic substance metabolic process), GO:0006807 (nitrogen compound metabolic process), GO:0044249 (cellular biosynthetic process), GO:0034641 (cellular nitrogen compound metabolic process), GO:0043603 (amide metabolic process), GO:1901564 (organonitrogen compound metabolic process), GO:1901576 (organic substance biosynthetic process), GO:0044260 (cellular macromolecule metabolic process), GO:0043170 (macromolecule metabolic process), GO:0006413 (translational initiation), GO:0019538 (protein metabolic process), GO:1901566 (organonitrogen compound biosynthetic process), GO:0006412 (translation), GO:0009059 (macromolecule biosynthetic process), GO:0043604 (amide biosynthetic process), GO:0044271 (cellular nitrogen compound biosynthetic process), GO:0034645 (cellular macromolecule biosynthetic process), GO:0006518 (peptide metabolic process), GO:0010467 (gene expression), GO:0043043 (peptide biosynthetic process)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0032991 (protein-containing complex), GO:0005737 (cytoplasm), GO:0005622 (intracellular anatomical structure)