Q8R000 · OSTA_MOUSE
- ProteinOrganic solute transporter subunit alpha
- GeneSlc51a
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids340 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Essential component of the Ost-alpha/Ost-beta complex, a heterodimer that acts as the intestinal basolateral transporter responsible for bile acid export from enterocytes into portal blood (PubMed:15563450, PubMed:16317684, PubMed:17650074, PubMed:18292224, PubMed:22535958).
Efficiently transports the major species of bile acids (taurocholate) (PubMed:16317684, PubMed:17650074, PubMed:18292224, PubMed:22535958).
Taurine conjugates are transported more efficiently across the basolateral membrane than glycine-conjugated bile acids (PubMed:16317684).
Can also transport steroids such as estrone 3-sulfate and dehydroepiandrosterone 3-sulfate, therefore playing a role in the enterohepatic circulation of sterols (By similarity).
Able to transport eicosanoids such as prostaglandin E2 (By similarity).
Efficiently transports the major species of bile acids (taurocholate) (PubMed:16317684, PubMed:17650074, PubMed:18292224, PubMed:22535958).
Taurine conjugates are transported more efficiently across the basolateral membrane than glycine-conjugated bile acids (PubMed:16317684).
Can also transport steroids such as estrone 3-sulfate and dehydroepiandrosterone 3-sulfate, therefore playing a role in the enterohepatic circulation of sterols (By similarity).
Able to transport eicosanoids such as prostaglandin E2 (By similarity).
Catalytic activity
- taurocholate(out) = taurocholate(in)
- tauroursodeoxycholate(out) = tauroursodeoxycholate(in)
- glycoursodeoxycholate(out) = glycoursodeoxycholate(in)
- glycocholate(out) = glycocholate(in)
- taurochenodeoxycholate(out) = taurochenodeoxycholate(in)
- glycochenodeoxycholate(out) = glycochenodeoxycholate(in)
- taurodeoxycholate(out) = taurodeoxycholate(in)
- glycodeoxycholate(out) = glycodeoxycholate(in)
- prostaglandin E2(out) = prostaglandin E2(in)
- estrone 3-sulfate(out) = estrone 3-sulfate(in)
- dehydroepiandrosterone 3-sulfate(out) = dehydroepiandrosterone 3-sulfate(in)
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | basolateral plasma membrane | |
Cellular Component | endoplasmic reticulum membrane | |
Cellular Component | membrane | |
Cellular Component | plasma membrane | |
Cellular Component | protein-containing complex | |
Molecular Function | bile acid transmembrane transporter activity | |
Molecular Function | protein heterodimerization activity | |
Molecular Function | protein homodimerization activity | |
Molecular Function | transmembrane transporter activity | |
Biological Process | bile acid and bile salt transport | |
Biological Process | bile acid secretion |
Keywords
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameOrganic solute transporter subunit alpha
- Short namesOST-alpha
- Alternative names
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Glires > Rodentia > Myomorpha > Muroidea > Muridae > Murinae > Mus > Mus
Accessions
- Primary accessionQ8R000
Proteomes
Organism-specific databases
Subcellular Location
UniProt Annotation
GO Annotation
Cell membrane ; Multi-pass membrane protein
Endoplasmic reticulum membrane ; Multi-pass membrane protein
Note: Mainly restricted to the lateral and basal membranes of ileal enterocytes. Transported from the endoplasmic reticulum to the plasma membrane upon interacting with SLC51B.
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 1-48 | Extracellular | ||||
Sequence: MEPGRTHIKLDPRYTAELLELLETNYSISPACFSHPPTAAQLLRALGP | ||||||
Transmembrane | 49-69 | Helical | ||||
Sequence: VDIALTIILTFLTTGSVAIFL | ||||||
Topological domain | 70-87 | Cytoplasmic | ||||
Sequence: EDAVYLYKNTLCPIKKRT | ||||||
Transmembrane | 88-108 | Helical | ||||
Sequence: LIWSSSAPTVVSVFCCFGLWI | ||||||
Topological domain | 109-114 | Extracellular | ||||
Sequence: PRALTL | ||||||
Transmembrane | 115-135 | Helical | ||||
Sequence: VEMAITSFYAVCFYLLMMVMV | ||||||
Topological domain | 136-181 | Cytoplasmic | ||||
Sequence: EGFGGKKAVLRTLKDTPMRVHTGPCCCCCPCCPPLILTRKKLQLLL | ||||||
Transmembrane | 182-202 | Helical | ||||
Sequence: LGPFQYAFFKITLSIVGLFLI | ||||||
Topological domain | 203-219 | Extracellular | ||||
Sequence: PDGIYDPGEISEKSAAL | ||||||
Transmembrane | 220-240 | Helical | ||||
Sequence: WINNLLAVSTLLALWSLAILF | ||||||
Topological domain | 241-255 | Cytoplasmic | ||||
Sequence: RQAKMHLGEQNMGSK | ||||||
Transmembrane | 256-276 | Helical | ||||
Sequence: FALFQVLVILTALQPAIFSIL | ||||||
Topological domain | 277-297 | Extracellular | ||||
Sequence: ANSGQIACSPPYSSKIRSQVM | ||||||
Transmembrane | 298-317 | Helical | ||||
Sequence: NCHMLILETFLMTVLTRMYY | ||||||
Topological domain | 318-340 | Cytoplasmic | ||||
Sequence: RRKDDKVGYEACSLPDLDSALKA |
Keywords
- Cellular component
Phenotypes & Variants
Disruption phenotype
Mice are physically indistinguishable from wild-type mice but display strongly reduced transileal transport of taurocholate. Moreover, the bile acid pool size is significantly reduced, but fecal bile acid excretion is not elevated.
Variants
We now provide the "Disease & Variants" viewer in its own tab.
The viewer provides 15 variants from UniProt as well as other sources including ClinVar and dbSNP.
Chemistry
PTM/Processing
Features
Showing features for chain, glycosylation, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000331544 | 1-340 | Organic solute transporter subunit alpha | |||
Sequence: MEPGRTHIKLDPRYTAELLELLETNYSISPACFSHPPTAAQLLRALGPVDIALTIILTFLTTGSVAIFLEDAVYLYKNTLCPIKKRTLIWSSSAPTVVSVFCCFGLWIPRALTLVEMAITSFYAVCFYLLMMVMVEGFGGKKAVLRTLKDTPMRVHTGPCCCCCPCCPPLILTRKKLQLLLLGPFQYAFFKITLSIVGLFLIPDGIYDPGEISEKSAALWINNLLAVSTLLALWSLAILFRQAKMHLGEQNMGSKFALFQVLVILTALQPAIFSILANSGQIACSPPYSSKIRSQVMNCHMLILETFLMTVLTRMYYRRKDDKVGYEACSLPDLDSALKA | ||||||
Glycosylation | 25 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Modified residue | 330 | Phosphoserine | ||||
Sequence: S |
Post-translational modification
N-glycosylated.
Keywords
- PTM
Proteomic databases
PTM databases
Expression
Tissue specificity
Present at high levels in ileum. In ileum, it is restricted to the apical domain on the mature villus enterocytes with little detectable expression in the goblet cells or crypt enterocytes (at protein level). Expressed in kidney but not in heart, brain, liver, spleen, embryo, lung, thymus, ovary nor testis.
Induction
Positively regulated via the bile acid-activated nuclear receptor farnesoid X receptor (NR1H4/FXR). Up-regulated in mice lacking Mrp4, but it is unable to compensate for the absence of Mrp4.
Gene expression databases
Structure
Sequence
- Sequence statusComplete
- Length340
- Mass (Da)37,759
- Last updated2002-06-01 v1
- Checksum5A072346AB5402F7
Computationally mapped potential isoform sequences
There is 1 potential isoform mapped to this entry
Entry | Entry name | Gene name | Length | ||
---|---|---|---|---|---|
A0A338P6E4 | A0A338P6E4_MOUSE | Slc51a | 178 |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AK052725 EMBL· GenBank· DDBJ | BAC35116.1 EMBL· GenBank· DDBJ | mRNA | ||
AK147155 EMBL· GenBank· DDBJ | BAE27722.1 EMBL· GenBank· DDBJ | mRNA | ||
BC024441 EMBL· GenBank· DDBJ | AAH24441.1 EMBL· GenBank· DDBJ | mRNA | ||
BC025912 EMBL· GenBank· DDBJ | AAH25912.1 EMBL· GenBank· DDBJ | mRNA | ||
BC031178 EMBL· GenBank· DDBJ | AAH31178.1 EMBL· GenBank· DDBJ | mRNA |