SAR1A
entrez
56681
canonical
uniprot
Q9NR31
canonical
ensembl
ENSG00000079332
resolver
ensp
ENSP00000362338
resolver
ensp
ENSP00000362339
resolver
genesymbol
SAR1A
resolver
genesymbol_syn
SAR1
resolver
genesymbol_syn
SARA
resolver
genesymbol_syn
SARA1
resolver
hgnc
HGNC:10534
resolver
uniprot
B4DQ19
resolver
uniprot
Q5SQT9
resolver
uniprot_entry
Q5SQT9_HUMAN
resolver
uniprot_entry
SAR1A_HUMAN
resolver
uniprot_sec
B4DQ19
resolver
activity_regulation
ACTIVITY REGULATION: Small GTPases activation is mediated by guanine exchange factors (GEF), while inactivation through hydrolysis of the bound GTP is stimulated by GTPase activating proteins (GAP). Activated by the guanine nucleotide exchange factor PREB/SEC12 that facilitates the loading of SAR1B with GTP (PubMed:32358066). Inhibited by the alarmone ppGpp (PubMed:36369712). {ECO:0000269|PubMed:32358066, ECO:0000269|PubMed:36369712}.
uniprot
proteins
amino_acid_sequence
MSFIFEWIYNGFSSVLQFLGLYKKSGKLVFLGLDNAGKTTLLHMLKDDRLGQHVPTLHPTSEELTIAGMTFTTFDLGGHEQARRVWKNYLPAINGIVFLVDCADHSRLVESKVELNALMTDETISNVPILILGNKIDRTDAISEEKLREIFGLYGQTTGKGNVTLKELNARPMEVFMCSVLKRQGYGEGFRWLSQYID
uniprot
proteins
ec_number
3.6.5.2
uniprot
proteins
function
FUNCTION: Small GTPase that cycles between an active GTP-bound and an inactive GDP-bound state and mainly functions in vesicle-mediated endoplasmic reticulum (ER) to Golgi transport. The active GTP-bound form inserts into the endoplasmic reticulum membrane where it recruits the remainder of the coat protein complex II/COPII. The coat protein complex II assembling and polymerizing on endoplasmic reticulum membrane is responsible for both the sorting of cargos and the deformation and budding of membranes into vesicles destined to the Golgi (PubMed:23433038, PubMed:32358066, PubMed:36369712). The GTPase activity of SAR1 by controlling the timing of COPII budding regulates the size of the formed vesicles and is important for cargo selection depending on their size (PubMed:32358066). Together with SEC16A, forms the organized scaffold defining endoplasmic reticulum exit sites (ERES), some specific domains of the endoplasmic reticulum where COPII vesicles form (PubMed:17005010). In addition to its role in vesicle trafficking, can also function as a leucine sensor regulating TORC1 signaling and more indirectly cellular metabolism, growth and survival. In absence of leucine, interacts with the GATOR2 complex via MIOS and inhibits TORC1 signaling. The binding of leucine abrogates the interaction with GATOR2 and the inhibition of the TORC1 signaling. This function is completely independent of the GTPase activity of SAR1B (PubMed:34290409). {ECO:0000269|PubMed:17005010, ECO:0000269|PubMed:23433038, ECO:0000269|PubMed:32358066, ECO:0000269|PubMed:34290409, ECO:0000269|PubMed:36369712}.
uniprot
proteins
mass_dalton
22367
uniprot
proteins
mutagenesis
MUTAGEN 79; /note="H->G: Decreases transport of STING1 from the endoplasmic reticulum to the Golgi."; /evidence="ECO:0000269|PubMed:32690950
uniprot
proteins
protein_family
SAR1 family
uniprot
proteins
protein_family
Small GTPase superfamily
uniprot
proteins
pubmed
10871277
uniprot
proteins
pubmed
11230166
uniprot
proteins
pubmed
14702039
uniprot
proteins
pubmed
15164054
uniprot
proteins
pubmed
15489334
uniprot
proteins
pubmed
17005010
uniprot
proteins
pubmed
17499046
uniprot
proteins
pubmed
18669648
uniprot
proteins
pubmed
19181664
uniprot
proteins
pubmed
20068231
uniprot
proteins
pubmed
21269460
uniprot
proteins
pubmed
23186163
uniprot
proteins
pubmed
23433038
uniprot
proteins
pubmed
24275569
uniprot
proteins
pubmed
25944712
uniprot
proteins
pubmed
32358066
uniprot
proteins
pubmed
32690950
uniprot
proteins
pubmed
32929276
uniprot
proteins
pubmed
34290409
uniprot
proteins
pubmed
36369712
uniprot
proteins
sequence_length
198
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Endoplasmic reticulum membrane {ECO:0000269|PubMed:23433038, ECO:0000269|PubMed:32358066}; Peripheral membrane protein {ECO:0000305|PubMed:23433038, ECO:0000305|PubMed:32358066}. Golgi apparatus, Golgi stack membrane {ECO:0000305|PubMed:34290409}; Peripheral membrane protein {ECO:0000305|PubMed:34290409}. Cytoplasm, cytosol {ECO:0000269|PubMed:34290409}. Lysosome membrane {ECO:0000305|PubMed:34290409}. Note=Active at endoplasmic reticulum exit sites (ERES) where it inserts into the membrane and recruits the remainder of the coat protein complex II/COPII (PubMed:23433038, PubMed:32358066). Upon leucine deprivation, associates with lysosomal membranes to repress TORC1 signaling (Probable). {ECO:0000269|PubMed:23433038, ECO:0000269|PubMed:32358066, ECO:0000305|PubMed:34290409}.
uniprot
proteins