Q8NBI5 · S43A3_HUMAN
- ProteinEquilibrative nucleobase transporter 1
- GeneSLC43A3
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids491 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Sodium-independent purine-selective nucleobase transporter which mediates the equilibrative transport of extracellular purine nucleobases such as adenine, guanine and hypoxanthine (PubMed:26455426, PubMed:32339528).
May regulate fatty acid (FA) transport in adipocytes, acting as a positive regulator of FA efflux and as a negative regulator of FA uptake (By similarity).
May regulate fatty acid (FA) transport in adipocytes, acting as a positive regulator of FA efflux and as a negative regulator of FA uptake (By similarity).
Isoform 1
Sodium-independent purine-selective nucleobase transporter which mediates the equilibrative transport of extracellular purine nucleobase adenine (PubMed:30910793).
Mediates the influx and efflux of the purine nucleobase analog drug 6-mercaptopurine across the membrane (PubMed:30910793).
Mediates the influx and efflux of the purine nucleobase analog drug 6-mercaptopurine across the membrane (PubMed:30910793).
Isoform 2
Sodium-independent purine-selective nucleobase transporter which mediates the equilibrative transport of extracellular purine nucleobase adenine (PubMed:30910793).
Mediates the influx and efflux of the purine nucleobase analog drug 6-mercaptopurine across the membrane (PubMed:30910793).
Mediates the influx and efflux of the purine nucleobase analog drug 6-mercaptopurine across the membrane (PubMed:30910793).
Catalytic activity
Isoform 1
adenine(out) = adenine(in)This reaction proceeds in the forward direction.Isoform 2
adenine(out) = adenine(in)This reaction proceeds in the forward direction.- guanine(out) = guanine(in)This reaction proceeds in the forward direction.
- hypoxanthine(out) = hypoxanthine(in)This reaction proceeds in the forward direction.
Activity regulation
Adenine transport is strongly inhibited by decynium-22.
Isoform 1
6-mercaptopurine-transport is inhibited by 6-thioguanine, 6-methylmercaptopurine and decynium-22.
Isoform 2
6-mercaptopurine-transport is inhibited by 6-thioguanine, 6-methylmercaptopurine and decynium-22.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.94 μM | adenine | |||||
0.268 μM | adenine | |||||
37 μM | adenine (isoform 1) | |||||
40 μM | adenine (isoform 2) | |||||
1.7 μM | guanine | |||||
1.32 μM | hypoxanthine | |||||
163 μM | 6-mercaptopurine (isoform 1) | |||||
188 μM | 6-mercaptopurine (isoform 2) |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
107.8 pmol/min/mg | for adenine uptake | ||||
14.1 pmol/min/mg | for adenine uptake | ||||
34 pmol/sec/mg | for adenine uptake (isoform 1) | ||||
7.9 pmol/sec/mg | for adenine uptake (isoform 2) | ||||
98.2 pmol/min/mg | for guanine uptake | ||||
73.1 pmol/min/mg | for hypoxanthine uptake | ||||
82 pmol/sec/mg | for 6-mercaptopurine uptake (isoform 1) | ||||
32 pmol/sec/mg | for 6-mercaptopurine uptake (isoform 2) |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | basolateral plasma membrane | |
Molecular Function | adenine transmembrane transporter activity | |
Molecular Function | fatty acid transmembrane transporter activity | |
Molecular Function | guanine transmembrane transporter activity | |
Molecular Function | xenobiotic transmembrane transporter activity | |
Biological Process | hypoxanthine transport |
Keywords
- Biological process
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended nameEquilibrative nucleobase transporter 1
- Alternative names
Gene names
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo
Accessions
- Primary accessionQ8NBI5
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
UniProt Annotation
GO Annotation
Basolateral cell membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 17-37 | Helical | ||||
Sequence: LLECLGFAGVLFGWPSLVFVF | ||||||
Transmembrane | 72-92 | Helical | ||||
Sequence: LIFTLGSFMNNFMTFPTGYIF | ||||||
Transmembrane | 102-122 | Helical | ||||
Sequence: LIAIFFYTTATLIIAFTSAGS | ||||||
Transmembrane | 123-143 | Helical | ||||
Sequence: AVLLFLAMPMLTIGGILFLIT | ||||||
Transmembrane | 156-176 | Helical | ||||
Sequence: STIITLYNGAFDSSSAVFLII | ||||||
Transmembrane | 188-208 | Helical | ||||
Sequence: ASFIFISVCSTWHVARTFLLM | ||||||
Transmembrane | 279-299 | Helical | ||||
Sequence: FAWHLVWLSVIQLWHYLFIGT | ||||||
Transmembrane | 319-339 | Helical | ||||
Sequence: TNAFAFTQFGVLCAPWNGLLM | ||||||
Transmembrane | 356-376 | Helical | ||||
Sequence: STLAVALCSTVPSLALTSLLC | ||||||
Transmembrane | 396-418 | Helical | ||||
Sequence: ILQVISRSFLYGSNAAFLTLAFP | ||||||
Transmembrane | 427-447 | Helical | ||||
Sequence: GLVMALSAVVSLLQFPIFTLI | ||||||
Transmembrane | 456-476 | Helical | ||||
Sequence: FYVNVMFMLAILLTFFHPFLV |
Keywords
- Cellular component
Disease & Variants
Features
Showing features for natural variant.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Natural variant | VAR_035156 | 53 | in dbSNP:rs34799622 | |||
Sequence: P → L |
Variants
We now provide the "Disease & Variants" viewer in its own tab.
The viewer provides 585 variants from UniProt as well as other sources including ClinVar and dbSNP.
Organism-specific databases
Miscellaneous
Chemistry
Genetic variation databases
PTM/Processing
Features
Showing features for chain, glycosylation, modified residue (large scale data), modified residue.
Type | ID | Position(s) | Source | Description | |||
---|---|---|---|---|---|---|---|
Chain | PRO_0000305036 | 1-491 | UniProt | Equilibrative nucleobase transporter 1 | |||
Sequence: MAGQGLPLHVATLLTGLLECLGFAGVLFGWPSLVFVFKNEDYFKDLCGPDAGPIGNATGQADCKAQDERFSLIFTLGSFMNNFMTFPTGYIFDRFKTTVARLIAIFFYTTATLIIAFTSAGSAVLLFLAMPMLTIGGILFLITNLQIGNLFGQHRSTIITLYNGAFDSSSAVFLIIKLLYEKGISLRASFIFISVCSTWHVARTFLLMPRGHIPYPLPPNYSYGLCPGNGTTKEEKETAEHENRELQSKEFLSAKEETPGAGQKQELRSFWSYAFSRRFAWHLVWLSVIQLWHYLFIGTLNSLLTNMAGGDMARVSTYTNAFAFTQFGVLCAPWNGLLMDRLKQKYQKEARKTGSSTLAVALCSTVPSLALTSLLCLGFALCASVPILPLQYLTFILQVISRSFLYGSNAAFLTLAFPSEHFGKLFGLVMALSAVVSLLQFPIFTLIKGSLQNDPFYVNVMFMLAILLTFFHPFLVYRECRTWKESPSAIA | |||||||
Glycosylation | 56 | UniProt | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | |||||||
Glycosylation | 220 | UniProt | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | |||||||
Glycosylation | 229 | UniProt | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | |||||||
Modified residue (large scale data) | 248 | PRIDE | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue | 253 | UniProt | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue (large scale data) | 253 | PRIDE | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue | 258 | UniProt | Phosphothreonine | ||||
Sequence: T | |||||||
Modified residue (large scale data) | 258 | PRIDE | Phosphothreonine | ||||
Sequence: T |
Keywords
- PTM
Proteomic databases
PTM databases
Expression
Tissue specificity
Widely expressed with highest levels in the liver and lung, followed by the pancreas (PubMed:26455426).
Highly expressed in macrophages (Ref.1)
Highly expressed in macrophages (Ref.1)
Gene expression databases
Organism-specific databases
Interaction
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | Q8NBI5 | VCP P55072 | 3 | EBI-2855542, EBI-355164 |
Protein-protein interaction databases
Miscellaneous
Structure
Sequence & Isoform
- Sequence statusComplete
This entry describes 2 isoforms produced by Alternative splicing.
Q8NBI5-1
This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
- Name1
- Length491
- Mass (Da)54,529
- Last updated2007-10-02 v2
- ChecksumC6BC8E48F38B1D8C
Q8NBI5-2
- Name2
- Differences from canonical
- 61-61: A → AGRLGCMGDLFSTP
Computationally mapped potential isoform sequences
There are 16 potential isoforms mapped to this entry
Entry | Entry name | Gene name | Length | ||
---|---|---|---|---|---|
H0YD64 | H0YD64_HUMAN | SLC43A3 | 137 | ||
E9PS74 | E9PS74_HUMAN | SLC43A3 | 331 | ||
E9PSH9 | E9PSH9_HUMAN | SLC43A3 | 119 | ||
E9PPE4 | E9PPE4_HUMAN | SLC43A3 | 101 | ||
E9PR94 | E9PR94_HUMAN | SLC43A3 | 126 | ||
E9PR64 | E9PR64_HUMAN | SLC43A3 | 169 | ||
E9PMZ1 | E9PMZ1_HUMAN | SLC43A3 | 148 | ||
E9PNM4 | E9PNM4_HUMAN | SLC43A3 | 63 | ||
E9PKW3 | E9PKW3_HUMAN | SLC43A3 | 133 | ||
E9PLP1 | E9PLP1_HUMAN | SLC43A3 | 82 | ||
E9PLF2 | E9PLF2_HUMAN | SLC43A3 | 107 | ||
E9PLW1 | E9PLW1_HUMAN | SLC43A3 | 97 | ||
E9PJL1 | E9PJL1_HUMAN | SLC43A3 | 44 | ||
E9PJL3 | E9PJL3_HUMAN | SLC43A3 | 109 | ||
E9PJT6 | E9PJT6_HUMAN | SLC43A3 | 78 | ||
E9PL23 | E9PL23_HUMAN | SLC43A3 | 22 |
Features
Showing features for alternative sequence, sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Alternative sequence | VSP_055620 | 61 | in isoform 2 | |||
Sequence: A → AGRLGCMGDLFSTP | ||||||
Sequence conflict | 172 | in Ref. 2; BAG60330 | ||||
Sequence: V → A | ||||||
Sequence conflict | 459 | in Ref. 4; BAC11695 | ||||
Sequence: N → D |
Keywords
- Coding sequence diversity
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AB028927 EMBL· GenBank· DDBJ | BAB82466.1 EMBL· GenBank· DDBJ | mRNA | ||
AK298028 EMBL· GenBank· DDBJ | BAG60330.1 EMBL· GenBank· DDBJ | mRNA | ||
CR457391 EMBL· GenBank· DDBJ | CAG33672.1 EMBL· GenBank· DDBJ | mRNA | ||
AK075552 EMBL· GenBank· DDBJ | BAC11695.1 EMBL· GenBank· DDBJ | mRNA | ||
AL157431 EMBL· GenBank· DDBJ | CAB75655.1 EMBL· GenBank· DDBJ | mRNA | ||
AP000781 EMBL· GenBank· DDBJ | - | Genomic DNA | No translation available. | |
CH471076 EMBL· GenBank· DDBJ | EAW73741.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BC003163 EMBL· GenBank· DDBJ | AAH03163.1 EMBL· GenBank· DDBJ | mRNA |