CPLM 1.0 - Compendium of Protein Lysine Modification
TagContent
CPLM ID CPLM-002667
UniProt Accession
Genbank Protein ID
Genbank Nucleotide ID
Protein Name
 Guanine nucleotide-binding protein alpha-1 subunit 
Protein Synonyms/Alias
 GP1-alpha 
Gene Name
 GPA1 
Gene Synonyms/Alias
 CDC70; DAC1; SCG1; YHR005C 
Created Date
 July 27, 2013 
Organism
 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) 
NCBI Taxa ID
 559292 
Lysine Modification
Position
Peptide
Type
References
35EQSLQLEKQRDKNEIubiquitination[1]
165VQSTGRAKAAFDEDGubiquitination[1, 2]
209INLQDICKDLNQEGDubiquitination[1]
295CTDEDILKGRIKTTGubiquitination[1]
425AGLKYFEKIFLSLNKubiquitination[1]
Reference
 [1] Global analysis of phosphorylation and ubiquitylation cross-talk in protein degradation.
 Swaney DL, Beltrao P, Starita L, Guo A, Rush J, Fields S, Krogan NJ, Villén J.
 Nat Methods. 2013 Jul;10(7):676-82. [PMID: 23749301]
 [2] Identification, analysis, and prediction of protein ubiquitination sites.
 Radivojac P, Vacic V, Haynes C, Cocklin RR, Mohan A, Heyen JW, Goebl MG, Iakoucheva LM.
 Proteins. 2010 Feb 1;78(2):365-80. [PMID: 19722269] 
Functional Description
 Alpha subunit of the heterotrimeric guanine nucleotide- binding protein (G protein) that mediates mating pheromone signal transduction. Binding of alpha-factor or a-factor to its cognate transmembrane receptor STE2 and STE3, respectively, allows the receptor to serve as a guanine nucleotide exchange factor (GEF) on GPA1. The exchange of GDP for GTP on the G protein alpha subunit alters its interaction with the G protein beta subunit STE4, leading to dissociation of the G protein beta-gamma dimer STE4- STE18. The dissociated subunits activate downstream effectors to activate the mating response pathway and induce changes necessary to produce mating-competent cells. STE4-STE18 activate the downstream pheromone signaling MAP kinase cascade leading to expression of mating-specific genes, inducing cell cycle arrest in G1, promoting polarized cell growth to form mating projections (shmoos), and establishing the changes in plasma membrane, cell wall and nuclear envelope to permit cell-cell fusion (plasmogamy) and fusion of the two haploid nuclei (karyogamy). GPA1 transmits a signal that requires direct binding to the effector enzyme PI3K located at the endosome, promoting increased PI3 production. The intrinsic GTPase activity of GPA1 determines the duration of signaling, and is dramatically accelerated by the RGS protein SST2. In unstimulated cells, GDP-bound GPA1 sequesters the G protein beta-gamma subunit STE4-STE18, preventing it from activating the downstream effectors. Also down-regulates the signal by inhibiting the pheromone-induced accumulation of FUS3 in the nucleus. 
Sequence Annotation
 NP_BIND 48 55 GTP (By similarity).
 NP_BIND 294 300 GTP (By similarity).
 NP_BIND 319 323 GTP (By similarity).
 NP_BIND 388 391 GTP (By similarity).
 REGION 127 235 Insert; not present in other G-proteins.
 METAL 55 55 Magnesium (By similarity).
 METAL 300 300 Magnesium (By similarity).
 BINDING 444 444 GTP; via amide nitrogen (By similarity).
 LIPID 2 2 N-myristoyl glycine.
 LIPID 3 3 S-palmitoyl cysteine.
 CROSSLNK 165 165 Glycyl lysine isopeptide (Lys-Gly)  
Keyword
 3D-structure; Cell membrane; Complete proteome; Endosome; GTP-binding; Isopeptide bond; Lipoprotein; Magnesium; Membrane; Metal-binding; Myristate; Nucleotide-binding; Palmitate; Pheromone response; Reference proteome; Transducer; Ubl conjugation. 
Sequence Source
 UniProt (SWISSPROT/TrEMBL); GenBank; EMBL 
Protein Length
 472 AA 
Protein Sequence
MGCTVSTQTI GDESDPFLQN KRANDVIEQS LQLEKQRDKN EIKLLLLGAG ESGKSTVLKQ 60
LKLLHQGGFS HQERLQYAQV IWADAIQSMK ILIIQARKLG IQLDCDDPIN NKDLFACKRI 120
LLKAKALDYI NASVAGGSDF LNDYVLKYSE RYETRRRVQS TGRAKAAFDE DGNISNVKSD 180
TDRDAETVTQ NEDADRNNSS RINLQDICKD LNQEGDDQMF VRKTSREIQG QNRRNLIHED 240
IAKAIKQLWN NDKGIKQCFA RSNEFQLEGS AAYYFDNIEK FASPNYVCTD EDILKGRIKT 300
TGITETEFNI GSSKFKVLDA GGQRSERKKW IHCFEGITAV LFVLAMSEYD QMLFEDERVN 360
RMHESIMLFD TLLNSKWFKD TPFILFLNKI DLFEEKVKSM PIRKYFPDYQ GRVGDAEAGL 420
KYFEKIFLSL NKTNKPIYVK RTCATDTQTM KFVLSAVTDL IIQQNLKKIG II 472 
Gene Ontology
 GO:0005768; C:endosome; IDA:SGD.
 GO:0010008; C:endosome membrane; IEA:UniProtKB-SubCell.
 GO:0005834; C:heterotrimeric G-protein complex; IDA:SGD.
 GO:0031683; F:G-protein beta/gamma-subunit complex binding; IBA:RefGenome.
 GO:0001664; F:G-protein coupled receptor binding; IBA:RefGenome.
 GO:0005525; F:GTP binding; IEA:UniProtKB-KW.
 GO:0003924; F:GTPase activity; IDA:SGD.
 GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
 GO:0004871; F:signal transducer activity; IBA:RefGenome.
 GO:0000754; P:adaptation of signaling pathway by response to pheromone involved in conjugation with cellular fusion; IMP:SGD.
 GO:0007189; P:adenylate cyclase-activating G-protein coupled receptor signaling pathway; IBA:RefGenome.
 GO:0031684; P:heterotrimeric G-protein complex cycle; IMP:SGD.
 GO:0048017; P:inositol lipid-mediated signaling; IMP:SGD.
 GO:0000742; P:karyogamy involved in conjugation with cellular fusion; IMP:SGD.
 GO:0000743; P:nuclear migration involved in conjugation with cellular fusion; IMP:SGD.
 GO:0000750; P:pheromone-dependent signal transduction involved in conjugation with cellular fusion; IMP:SGD.
 GO:0071701; P:regulation of MAPK export from nucleus; IMP:SGD. 
Interpro
 IPR002975; Fungi_Gprotein_alpha.
 IPR001019; Gprotein_alpha_su.
 IPR011025; GproteinA_insert.
 IPR027417; P-loop_NTPase. 
Pfam
 PF00503; G-alpha 
SMART
 SM00275; G_alpha 
PROSITE
  
PRINTS
 PR00318; GPROTEINA.
 PR01241; GPROTEINAFNG.