P32481 · IF2G_YEAST
- ProteinEukaryotic translation initiation factor 2 subunit gamma
- GeneGCD11
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids527 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
As a subunit of eukaryotic initiation factor 2 eIF2, 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.
Miscellaneous
Present with 20800 molecules/cell in log phase SD medium.
Catalytic activity
- GTP + H2O = GDP + H+ + phosphate
Features
Showing features for binding site.
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Cellular Component | eukaryotic 43S preinitiation complex | |
Cellular Component | eukaryotic 48S preinitiation complex | |
Cellular Component | eukaryotic translation initiation factor 2 complex | |
Cellular Component | multi-eIF complex | |
Cellular Component | ribosome | |
Molecular Function | GTP binding | |
Molecular Function | GTPase activity | |
Molecular Function | methionyl-initiator methionine tRNA binding | |
Molecular Function | translation initiation factor activity | |
Molecular Function | translation initiation factor binding | |
Biological Process | formation of translation preinitiation complex | |
Biological Process | positive regulation of translational fidelity | |
Biological Process | translational initiation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameEukaryotic translation initiation factor 2 subunit gamma
- EC number
- Short nameseIF2-gamma
Gene names
Organism names
- Strain
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Saccharomycotina > Saccharomycetes > Saccharomycetales > Saccharomycetaceae > Saccharomyces
Accessions
- Primary accessionP32481
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
Phenotypes & Variants
Disruption phenotype
Inviable.
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 135 | In SUI4; defective in ternary complex formation, correlating with a higher rate of dissociation from charged initiator-tRNA in the absence of GTP hydrolysis. | ||||
Sequence: N → K | ||||||
Mutagenesis | 142 | Reduces the affinity of eIF-2 for Met-tRNAi(Met) without affecting the k(off) value for guanine nucleotides. | ||||
Sequence: Y → H | ||||||
Mutagenesis | 203 | Impairs eIF2 complex function. Reduces cell population growth. | ||||
Sequence: T → A | ||||||
Mutagenesis | 203 | No effect on cell population growth. | ||||
Sequence: T → I or K | ||||||
Mutagenesis | 218 | No effect on cell population growth. | ||||
Sequence: I → A | ||||||
Mutagenesis | 218 | Impairs eIF2 complex function. Strongly reduces cell population growth. | ||||
Sequence: I → L | ||||||
Mutagenesis | 250 | Increases the off-rate for GDP, without altering the apparent dissociation constant for Met-tRNAi(Met). Mimicks the function of the guanine nucleotide exchange factor eIF-2B. | ||||
Sequence: K → R | ||||||
Mutagenesis | 281 | Impairs eIF2 complex formation by impairing binding to SUI3 but not SUI2. Reduces cell population growth. | ||||
Sequence: V → K | ||||||
Mutagenesis | 281 | Abolishes binding to SUI3 but not to SUI2 or CDC123. Abolishes interactions with the eIF2B complex subunits GCD6 and GCD7. | ||||
Sequence: V → R | ||||||
Mutagenesis | 281 | No effect on cell population growth. | ||||
Sequence: V → T | ||||||
Mutagenesis | 318 | Mildly impairs eIF2 complex function. No effect on cell population growth. | ||||
Sequence: I → L | ||||||
Mutagenesis | 318 | Impairs binding to methionyl-initiator methionine tRNA and impairs eIF2 complex function. Mildly reduces cell population growth. | ||||
Sequence: I → M | ||||||
Mutagenesis | 325-331 | Disrupts binding to CDC123 and SUI2. Does not affect interaction with SUI3. | ||||
Sequence: Missing | ||||||
Mutagenesis | 403 | Abolishes binding to SUI2 but not to SUI3 or CDC123. Abolishes interactions with the eIF2B complex subunits GCD6 and GCD7. Decreases cell population growth. | ||||
Sequence: D → R | ||||||
Mutagenesis | 490 | Mildly impairs eIF2 complex function. | ||||
Sequence: P → S | ||||||
Mutagenesis | 504 | Disrupts binding to CDC123. | ||||
Sequence: R → A | ||||||
Mutagenesis | 509 | Disrupts binding to CDC123. | ||||
Sequence: W → A | ||||||
Mutagenesis | 515-527 | Disrupts eIF2 complex formation and binding to CDC123. | ||||
Sequence: Missing |
PTM/Processing
Features
Showing features for chain, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000137448 | 1-527 | Eukaryotic translation initiation factor 2 subunit gamma | |||
Sequence: MSDLQDQEPSIIINGNLEPVGEPDIVEETEVVAQETQETQDADKPKKKVAFTGLEEDGETEEEKRKREFEEGGGLPEQPLNPDFSKLNPLSAEIINRQATINIGTIGHVAHGKSTVVRAISGVQTVRFKDELERNITIKLGYANAKIYKCQEPTCPEPDCYRSFKSDKEISPKCQRPGCPGRYKLVRHVSFVDCPGHDILMSTMLSGAAVMDAALLLIAGNESCPQPQTSEHLAAIEIMKLKHVIILQNKVDLMREESALEHQKSILKFIRGTIADGAPIVPISAQLKYNIDAVNEFIVKTIPVPPRDFMISPRLIVIRSFDVNKPGAEIEDLKGGVAGGSILNGVFKLGDEIEIRPGIVTKDDKGKIQCKPIFSNIVSLFAEQNDLKFAVPGGLIGVGTKVDPTLCRADRLVGQVVGAKGHLPNIYTDIEINYFLLRRLLGVKTDGQKQAKVRKLEPNEVLMVNIGSTATGARVVAVKADMARLQLTSPACTEINEKIALSRRIEKHWRLIGWATIKKGTTLEPIA | ||||||
Modified residue | 60 | Phosphothreonine | ||||
Sequence: T | ||||||
Modified residue | 258 | Phosphoserine | ||||
Sequence: S |
Keywords
- PTM
Proteomic databases
PTM databases
Interaction
Subunit
Eukaryotic translation initiation factor 2 eIF2 is a heterotrimeric complex composed of an alpha, a beta and a gamma subunit (PubMed:11018020, PubMed:16522633, PubMed:23775072, PubMed:30517694, PubMed:35031321).
The factors eIF-1, eIF-1A, eIF-2, eIF-3, TIF5/eIF-5 and methionyl-tRNAi form a multifactor complex (MFC) that may bind to the 40S ribosome (PubMed:11018020, PubMed:16522633).
Interacts (via C-terminus) with CDC123; the interaction is direct (PubMed:23775072, PubMed:26211610, PubMed:35031321, PubMed:37507029).
Interacts with GCD1 (PubMed:23775072).
Interacts with the eIF2B complex subunits GCD6 and GCD7 (PubMed:35031321).
Interacts with methionyl-initiator methionine tRNA (PubMed:30517694).
The factors eIF-1, eIF-1A, eIF-2, eIF-3, TIF5/eIF-5 and methionyl-tRNAi form a multifactor complex (MFC) that may bind to the 40S ribosome (PubMed:11018020, PubMed:16522633).
Interacts (via C-terminus) with CDC123; the interaction is direct (PubMed:23775072, PubMed:26211610, PubMed:35031321, PubMed:37507029).
Interacts with GCD1 (PubMed:23775072).
Interacts with the eIF2B complex subunits GCD6 and GCD7 (PubMed:35031321).
Interacts with methionyl-initiator methionine tRNA (PubMed:30517694).
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | P32481 | CDC123 Q05791 | 10 | EBI-8924, EBI-34676 | |
XENO | P32481 | cdc123 Q9P7N5 | 4 | EBI-8924, EBI-16165908 | |
BINARY | P32481 | SUI2 P20459 | 12 | EBI-8924, EBI-8915 | |
BINARY | P32481 | SUI3 P09064 | 6 | EBI-8924, EBI-8920 | |
BINARY | P32481 | TIF5 P38431 | 4 | EBI-8924, EBI-9038 |
Protein-protein interaction databases
Miscellaneous
Structure
Family & Domains
Features
Showing features for region, compositional bias, domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-83 | Disordered | ||||
Sequence: MSDLQDQEPSIIINGNLEPVGEPDIVEETEVVAQETQETQDADKPKKKVAFTGLEEDGETEEEKRKREFEEGGGLPEQPLNPD | ||||||
Compositional bias | 37-73 | Basic and acidic residues | ||||
Sequence: QETQDADKPKKKVAFTGLEEDGETEEEKRKREFEEGG | ||||||
Domain | 98-307 | tr-type G | ||||
Sequence: QATINIGTIGHVAHGKSTVVRAISGVQTVRFKDELERNITIKLGYANAKIYKCQEPTCPEPDCYRSFKSDKEISPKCQRPGCPGRYKLVRHVSFVDCPGHDILMSTMLSGAAVMDAALLLIAGNESCPQPQTSEHLAAIEIMKLKHVIILQNKVDLMREESALEHQKSILKFIRGTIADGAPIVPISAQLKYNIDAVNEFIVKTIPVPPR | ||||||
Region | 107-114 | G1 | ||||
Sequence: GHVAHGKS | ||||||
Region | 135-139 | G2 | ||||
Sequence: NITIK | ||||||
Region | 193-196 | G3 | ||||
Sequence: DCPG | ||||||
Region | 249-252 | G4 | ||||
Sequence: NKVD | ||||||
Region | 284-286 | G5 | ||||
Sequence: SAQ | ||||||
Region | 515-527 | Interacts with CDC123 | ||||
Sequence: ATIKKGTTLEPIA |
Sequence similarities
Belongs to the TRAFAC class translation factor GTPase superfamily. Classic translation factor GTPase family. EIF2G subfamily.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length527
- Mass (Da)57,866
- Last updated1993-10-01 v1
- ChecksumD498AE62BC3E81CD
Features
Showing features for compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 37-73 | Basic and acidic residues | ||||
Sequence: QETQDADKPKKKVAFTGLEEDGETEEEKRKREFEEGG |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
L04268 EMBL· GenBank· DDBJ | AAA34633.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U18778 EMBL· GenBank· DDBJ | AAB64558.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BK006939 EMBL· GenBank· DDBJ | DAA07678.1 EMBL· GenBank· DDBJ | Genomic DNA |