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Q9NP91 (S6A20_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 101. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (5) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Sodium- and chloride-dependent transporter XTRP3
Alternative name(s):
Sodium/imino-acid transporter 1
Solute carrier family 6 member 20
Transporter rB21A homolog
Gene names
Name:SLC6A20
Synonyms:SIT1, XT3, XTRP3
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length592 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Mediates the calcium-dependent uptake of imino acids such as L-proline, N-methyl-L-proline and pipecolate as well as N-methylated amino acids. Involved in the transport of glycine. Ref.7 Ref.8

Subcellular location

Apical cell membrane; Multi-pass membrane protein By similarity. Note: Located in the apical brush border membrane of kidney proximal tubule cells By similarity.

Tissue specificity

Kidney and small intestine. Expressed in the S3 segment of the proximal tubule. Ref.5 Ref.8

Involvement in disease

Hyperglycinuria (HG) [MIM:138500]: A condition characterized by excess of glycine in the urine. In some cases it is associated with renal colic and renal oxalate stones.
Note: The disease is caused by mutations affecting the gene represented in this entry. Ref.8

Iminoglycinuria (IG) [MIM:242600]: A disorder of renal tubular reabsorption of glycine and imino acids (proline and hydroxyproline), marked by excessive levels of all three substances in the urine.
Note: The disease is caused by mutations affecting the gene represented in this entry. Haploinsufficiency of SLC6A20 combined with deficiency of the neutral amino acid transporter SLC6A19 or partially inactivating mutations in SLC36A2, is responsible for iminoglycinuria. Additional polymorphisms and mutations in SLC6A18 can contribute to the IG phenotype in some families. Ref.8

Sequence similarities

Belongs to the sodium:neurotransmitter symporter (SNF) (TC 2.A.22) family. SLC6A20 subfamily. [View classification]

Sequence caution

The sequence AAL75944.1 differs from that shown. Reason: Erroneous initiation.

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: Q9NP91-1)

Also known as: XT3;

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.
Isoform 2 (identifier: Q9NP91-2)

Also known as: XT3a;

The sequence of this isoform differs from the canonical sequence as follows:
     195-231: Missing.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 592592Sodium- and chloride-dependent transporter XTRP3
PRO_0000214812

Regions

Topological domain1 – 55Cytoplasmic Potential
Transmembrane6 – 2621Helical; Name=1; Potential
Topological domain27 – 4216Extracellular Potential
Transmembrane43 – 6321Helical; Name=2; Potential
Topological domain64 – 7916Cytoplasmic Potential
Transmembrane80 – 10021Helical; Name=3; Potential
Topological domain101 – 16565Extracellular Potential
Transmembrane166 – 18621Helical; Name=4; Potential
Topological domain187 – 1948Cytoplasmic Potential
Transmembrane195 – 21521Helical; Name=5; Potential
Topological domain216 – 24126Extracellular Potential
Transmembrane242 – 26221Helical; Name=6; Potential
Topological domain263 – 27614Cytoplasmic Potential
Transmembrane277 – 29721Helical; Name=7; Potential
Topological domain298 – 38992Extracellular Potential
Transmembrane390 – 41021Helical; Name=8; Potential
Topological domain411 – 43121Cytoplasmic Potential
Transmembrane432 – 45221Helical; Name=9; Potential
Topological domain453 – 46513Extracellular Potential
Transmembrane466 – 48621Helical; Name=10; Potential
Topological domain487 – 50418Cytoplasmic Potential
Transmembrane505 – 52521Helical; Name=11; Potential
Topological domain526 – 55429Extracellular Potential
Transmembrane555 – 57521Helical; Name=12; Potential
Topological domain576 – 59217Cytoplasmic Potential

Amino acid modifications

Glycosylation1311N-linked (GlcNAc...) Potential
Glycosylation3571N-linked (GlcNAc...) Potential

Natural variations

Alternative sequence195 – 23137Missing in isoform 2.
VSP_050002
Natural variant91A → G.
Corresponds to variant rs2271615 [ dbSNP | Ensembl ].
VAR_021862
Natural variant1991T → M Common variant that contributes to hyperglycinuria and iminoglycinuria in patients carrying variants in SLC36A2, SLC6A19 or SLC6A18; results in SLC6A20 inactivation due to a 8-fold decrease of Vmax. Ref.8
Corresponds to variant rs17279437 [ dbSNP | Ensembl ].
VAR_052068

Experimental info

Sequence conflict311F → N in AAC27755. Ref.2
Sequence conflict2171L → V in AAC27755. Ref.2

Sequences

Sequence LengthMass (Da)Tools
Isoform 1 (XT3) [UniParc].

Last modified October 1, 2000. Version 1.
Checksum: AF6E94E19895377F

FASTA59265,914
        10         20         30         40         50         60 
MEKARPLWAN SLQFVFACIS YAVGLGNVWR FPYLCQMYGG GSFLVPYIIM LIVEGMPLLY 

        70         80         90        100        110        120 
LELAVGQRMR QGSIGAWRTI SPYLSGVGVA SVVVSFFLSM YYNVINAWAF WYLFHSFQDP 

       130        140        150        160        170        180 
LPWSVCPLNG NHTGYDEECE KASSTQYFWY RKTLNISPSL QENGGVQWEP ALCLLLAWLV 

       190        200        210        220        230        240 
VYLCILRGTE STGKVVYFTA SLPYCVLIIY LIRGLTLHGA TNGLMYMFTP KIEQLANPKA 

       250        260        270        280        290        300 
WINAATQIFF SLGLGFGSLI AFASYNEPSN NCQKHAIIVS LINSFTSIFA SIVTFSIYGF 

       310        320        330        340        350        360 
KATFNYENCL KKVSLLLTNT FDLEDGFLTA SNLEQVKGYL ASAYPSKYSE MFPQIKNCSL 

       370        380        390        400        410        420 
ESELDTAVQG TGLAFIVYTE AIKNMEVSQL WSVLYFFMLL MLGIGSMLGN TAAILTPLTD 

       430        440        450        460        470        480 
SKIISSHLPK EAISGLVCLV NCAIGMVFTM EAGNYWFDIF NDYAATLSLL LIVLVETIAV 

       490        500        510        520        530        540 
CYVYGLRRFE SDLKAMTGRA VSWYWKVMWA GVSPLLIVSL FVFYLSDYIL TGTLKYQAWD 

       550        560        570        580        590 
ASQGQLVTKD YPAYALAVIG LLVASSTMCI PLAALGTFVQ RRLKRGDADP VA 

« Hide

Isoform 2 (XT3a) [UniParc].

Checksum: A7CE6C1CE318CF69
Show »

FASTA55561,751

References

« Hide 'large scale' references
[1]"The LZTFL1 gene is a part of a transcriptional map covering 250 kb within the common eliminated region 1 (C3CER1) in 3p21.3."
Kiss H., Kedra D., Kiss C., Kost-Alimova M., Yang Y., Klein G., Imreh S., Dumanski J.P.
Genomics 73:10-19(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORMS 1 AND 2).
[2]"Cloning of a new human cDNA similar to Rattus norvegicus neurotransmitter transporter rB21a."
Zhou Y., Yu L., Zhao S.Y.
Submitted (FEB-2002) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. expand/collapse author list , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C.
Submitted (JUL-2005) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[4]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2).
[5]"Cloning, gene structure, and genomic localization of an orphan transporter from mouse kidney with six alternatively-spliced isoforms."
Nash S.R., Giros B., Kingsmore S.F., Kim K.M., El-Mestikawy S., Dong Q., Fumagalli F., Seldin M.F., Caron M.G.
Recept. Channels 6:113-128(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 1-315 (ISOFORM 1), TISSUE SPECIFICITY.
[6]The European IMAGE consortium
Submitted (JUL-2000) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 232-592.
[7]"Identification of mammalian proline transporter SIT1 (SLC6A20) with characteristics of classical system imino."
Takanaga H., Mackenzie B., Suzuki Y., Hediger M.A.
J. Biol. Chem. 280:8974-8984(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION.
[8]"Iminoglycinuria and hyperglycinuria are discrete human phenotypes resulting from complex mutations in proline and glycine transporters."
Broer S., Bailey C.G., Kowalczuk S., Ng C., Vanslambrouck J.M., Rodgers H., Auray-Blais C., Cavanaugh J.A., Broer A., Rasko J.E.
J. Clin. Invest. 118:3881-3892(2008) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, TISSUE SPECIFICITY, VARIANT MET-199, CHARACTERIZATION OF VARIANT MET-199, INVOLVEMENT IN HG AND IG.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AJ276207 mRNA. Translation: CAB99310.1.
AJ276208 mRNA. Translation: CAB99311.1.
AJ289880 Genomic DNA. Translation: CAB96872.1.
AF125107 mRNA. Translation: AAL75944.1. Different initiation.
CH471055 Genomic DNA. Translation: EAW64748.1.
BC126197 mRNA. Translation: AAI26198.1.
BC136431 mRNA. Translation: AAI36432.1.
AF075260 mRNA. Translation: AAC27755.1.
AL389979 mRNA. Translation: CAB97535.1.
RefSeqNP_064593.1. NM_020208.3.
NP_071800.1. NM_022405.3.
UniGeneHs.413095.

3D structure databases

ProteinModelPortalQ9NP91.
SMRQ9NP91. Positions 3-580.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING9606.ENSP00000346298.

Protein family/group databases

TCDB2.A.22.6.8. the neurotransmitter:sodium symporter (nss) family.

Polymorphism databases

DMDM46397768.

Proteomic databases

PaxDbQ9NP91.
PRIDEQ9NP91.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000353278; ENSP00000296133; ENSG00000163817. [Q9NP91-2]
ENST00000358525; ENSP00000346298; ENSG00000163817. [Q9NP91-1]
GeneID54716.
KEGGhsa:54716.
UCSCuc011bai.2. human. [Q9NP91-1]
uc011baj.2. human. [Q9NP91-2]

Organism-specific databases

CTD54716.
GeneCardsGC03M045796.
HGNCHGNC:30927. SLC6A20.
HPAHPA029873.
MIM138500. phenotype.
242600. phenotype.
605616. gene.
neXtProtNX_Q9NP91.
Orphanet42062. Iminoglycinuria.
PharmGKBPA134865308.
GenAtlasSearch...

Phylogenomic databases

eggNOGCOG0733.
HOGENOMHOG000116406.
HOVERGENHBG071421.
InParanoidQ9NP91.
KOK05048.
OMAATNGLMY.
OrthoDBEOG793B71.
PhylomeDBQ9NP91.
TreeFamTF343812.

Enzyme and pathway databases

ReactomeREACT_15518. Transmembrane transport of small molecules.
REACT_19419. Amino acid and oligopeptide SLC transporters.
REACT_20679. Amine compound SLC transporters.

Gene expression databases

ArrayExpressQ9NP91.
BgeeQ9NP91.
CleanExHS_SIT1.
HS_SLC6A20.
GenevestigatorQ9NP91.

Family and domain databases

InterProIPR000175. Na/ntran_symport.
IPR002438. Na/ntran_symport_orphan.
[Graphical view]
PANTHERPTHR11616. PTHR11616. 1 hit.
PfamPF00209. SNF. 1 hit.
[Graphical view]
PRINTSPR00176. NANEUSMPORT.
PR01206. ORPHTRNSPORT.
PROSITEPS00610. NA_NEUROTRAN_SYMP_1. 1 hit.
PS00754. NA_NEUROTRAN_SYMP_2. 1 hit.
PS50267. NA_NEUROTRAN_SYMP_3. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

GeneWikiSLC6A20.
GenomeRNAi54716.
NextBio57286.
PROQ9NP91.
SOURCESearch...

Entry information

Entry nameS6A20_HUMAN
AccessionPrimary (citable) accession number: Q9NP91
Secondary accession number(s): A1A4F2 expand/collapse secondary AC list , O75590, Q8TF10, Q9NPQ2, Q9NQ77
Entry history
Integrated into UniProtKB/Swiss-Prot: March 29, 2004
Last sequence update: October 1, 2000
Last modified: April 16, 2014
This is version 101 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

SIMILARITY comments

Index of protein domains and families

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human chromosome 3

Human chromosome 3: entries, gene names and cross-references to MIM