Contents

Search

solute carrier family 22 member 4 (SLC22A4, organic cation/carnitine transporter 1, ergothioneine transporter, ET transporter, ETT, OCTN1, UT2H)

Function: - Na+ dependent, low affinity carnitine transporter - stoichiometry: 1 Na+ with 1 carnitine - also transports organic cations such as tetraethylammonium (Na+ independent) - ergothioneine appears to be a substrate - interacts with PDZK1 (putative) Kinetic parameters: - KM=0.470 mM for TEA (37C & pH=7.4) - Vmax=0.974 nmol/min/mg enzyme toward TEA (37C & pH=7.4) - pH dependence: - more active at neutral & alkaline pHs than at acidic pH Structure: - belongs to the major facilitator superfamily, organic cation transporter family Compartment: membrane Expression: - widely expressed - expressed in blood, bone marrow, trachea, fetal liver, intestinal epithelial cells > kidney, skeletal muscle, prostate, lung, pancreas, placenta, heart, uterus, spleen & spinal cord - expressed in CD68 macrophage & CD43 T-cells but not in CD20 B-cells - predominantly expressed in CD14 cells in peripheral blood mononuclear cells - overexpressed upon TNF-alpha treatment Pathology: - defects in SLC22A4 may be a cause of susceptibility to Crohn's disease; highly expressed in intestinal cell types affected by Crohn's disease, including epithelial cells - defects in SLC22A4 may be a cause of rheumatoid arthritis

Related

inflammatory bowel disease

General

glycoprotein major facilitator superfamily (MFS) solute carrier family 22 (SLC22, SLC22A) transmembrane 12 protein

Properties

SIZE: MW = 62 kD entity length = 551 aa COMPARTMENT: cellular membrane MOTIF: cytoplasmic domain {1-20} transmembrane domain {21-41} exoplasmic loop {42-141} MOTIF: N-glycosylation site {N57} N-glycosylation site {N64} N-glycosylation site {N91} transmembrane domain {142-162} cytoplasmic loop {163-171} transmembrane domain {172-192} exoplasmic loop {193-197} transmembrane domain {198-218} ATP-binding site NAME: ATP-binding site SITE: 218-225 cytoplasmic loop {219-232} transmembrane domain {233-253} exoplasmic loop {254-257} transmembrane domain {258-278} cytoplasmic loop {279-337} transmembrane domain {338-358} exoplasmic loop {359-371} transmembrane domain {372-392} cytoplasmic loop {393-399} transmembrane domain {400-420} exoplasmic loop {421-426} transmembrane domain {427-447} cytoplasmic loop {448-460} transmembrane domain {461-481} exoplasmic loop {482-486} transmembrane domain {487-507} cytoplasmic domain {508-551}

Database Correlations

OMIM correlations UniProt Q9H015 Pfam PF07690 Kegg hsa:6583

References

  1. UniProt :accession Q9H015
  2. Gru:undemann D et al Drug excretion mediated by a new prototype of polyspecific transporter Nature. 1994 Dec 8;372(6506):549-52. PMID: 7990927