Organic anion-transporting polypeptide

Organic Anion Transporter Polypeptide (OATP) family
Identifiers
Symbol OATP
Pfam PF03137
InterPro IPR004156
TCDB 2.A.60

An organic anion-transporting polypeptide (OATP) is a membrane transport protein that mediates the transport of organic anions across the cell membrane. Organic anion-transporting proteins belong to the solute carrier family, more specific, subfamily 21 (organic anion transporting).[1]

Contents

Function

Organic anion transporters may carry bile acids as well as bilirubin over the basolateral membrane (facing sinusoids) in hepatocytes, as well as other anions for excretion in bile.[2]

They also transport the dye bromsulphthalein, availing it as a liver-testing substance.[2]

Other OAT proteins transport organic anions across the basolateral side of renal proximal tubule cells during renal secretion.

Proteins

These organic anion transporting proteins have been found in human cells.

Abbreviation Protein Name Location
SLCO1A2 Solute carrier organic anion transporter family member 1A2 Liver
SLCO1B1 Solute carrier organic anion transporter family member 1B1 Liver
SLCO1B3 Solute carrier organic anion transporter family member 1B3 Liver
SLCO1B4
SLCO1C1
SLCO2A1
SLCO2B1 Solute carrier organic anion transporter family member 2B1 Many
SLCO3A1 Solute carrier organic anion transporter family member 3A1
SLCO4A1 Solute carrier organic anion transporter family member 4A1
SLCO4C1 Kidneys
SLCO5A1
SLCO6A1

Organic anion transporter (OAT) family

The SLC22A gene family codes for organic anion transporter (OAT) proteins. The OAT family plays the central role in renal organic anion transport. OAT1, OAT3, OAT4, and URAT1 are expressed in the proximal tubular cells of the kidneys. OAT1 and OAT3 mediate uptake of a wide range of relatively small and hydrophilic organic anions from plasma. URAT1 transports those organic anions from the cytoplasm of the proximal tubular cells into the lumen of the nephron.[3] Organic anion transporters are within the organic cation transport proteins family.

Abbreviation Gene Protein Name Location
OAT1 SLC22A6 Solute carrier family 22 member 6
 Brain, placenta, eyes, smooth muscle,
and the basolateral membrane of renal proximal tubule cells
OAT2 SLC22A7 Solute carrier family 22 member 7
 Liver, and kidneys
OAT3 SLC22A8 Solute carrier family 22 member 8
 Bone, brain, eyes, liver, adrenal glands,
and the basolateral membrane of renal proximal tubule cells
OAT4 SLC22A11 Solute carrier family 22 member 11
 Placenta, and the apical membrane of the renal proximal tubule cells
OAT5 SLC22A10 Solute carrier family 22 member 10
 Kidneys
URAT1 SLC22A12 Solute carrier family 22 member 12
 Brain, vascular smooth muscle cells,
and the apical membrane of the renal proximal tubule cells

Pharmacology

Probenecid inhibits organic anion transporters.[4]

References

  1. ^ Hagenbuch B, Meier PJ (February 2004). "Organic anion transporting polypeptides of the OATP/ SLC21 family: phylogenetic classification as OATP/ SLCO superfamily, new nomenclature and molecular/functional properties". Pflugers Arch. 447 (5): 653–65. doi:10.1007/s00424-003-1168-y. PMID 14579113. 
  2. ^ a b Pages 980-990 in:Walter F., PhD. Boron (2003). Medical Physiology: A Cellular And Molecular Approaoch. Elsevier/Saunders. pp. 1300. ISBN 1-4160-2328-3. 
  3. ^ Sekine T, Miyazaki H, Endou H (February 2006). "Molecular physiology of renal organic anion transporters". Am. J. Physiol. Renal Physiol. 290 (2): F251–61. doi:10.1152/ajprenal.00439.2004. PMID 16403838. 
  4. ^ Price KL, Sautin YY, Long DA, Zhang L, Miyazaki H, Mu W, Endou H, Johnson RJ (July 2006). "Human vascular smooth muscle cells express a urate transporter". J. Am. Soc. Nephrol. 17 (7): 1791–5. doi:10.1681/ASN.2006030264. PMID 16775029.