SLC22A1 cDNA Clone – Solute Carrier Family 22 (Organic Cation Transporter), Member 1 (Human)

Polyspecific organic cation transporters in the liver, kidney, intestine, and other organs are critical for elimination of many endogenous small organic cations as well as a wide array of drugs and environmental toxins. This gene is one of three similar cation transporter genes located in a cluster on chromosome 6. The encoded protein contains twelve putative transmembrane domains and is a plasma integral membrane protein. Two transcript variants encoding two different isoforms have been found for this gene, but only the longer variant encodes a functional transporter. [provided by RefSeq, Jul 2008]

SLC22A1: Translocates a broad array of organic cations with various structures and molecular weights including the model compounds 1-methyl-4-phenylpyridinium (MPP), tetraethylammonium (TEA), N-1-methylnicotinamide (NMN), 4-(4-(dimethylamino)styryl)- N-methylpyridinium (ASP), the endogenous compounds choline, guanidine, histamine, epinephrine, adrenaline, noradrenaline and dopamine, and the drugs quinine, and metformin. The transport of organic cations is inhibited by a broad array of compounds like tetramethylammonium (TMA), cocaine, lidocaine, NMDA receptor antagonists, atropine, prazosin, cimetidine, TEA and NMN, guanidine, cimetidine, choline, procainamide, quinine, tetrabutylammonium, and tetrapentylammonium. Translocates organic cations in an electrogenic and pH-independent manner. Translocates organic cations across the plasma membrane in both directions. Transports the polyamines spermine and spermidine. Transports pramipexole across the basolateral membrane of the proximal tubular epithelial cells. The choline transport is activated by MMTS. Regulated by various intracellular signaling pathways including inhibition by protein kinase A activation, and endogenously activation by the calmodulin complex, the calmodulin- dependent kinase II and LCK tyrosine kinase. Belongs to the major facilitator (TC 2.A.1) superfamily. Organic cation transporter (TC 2.A.1.19) family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Transporter, SLC family; Transporter; Membrane protein, integral; Membrane protein, multi-pass

Chromosomal Location of Human Ortholog: 6q25.3

Cellular Component: integral to plasma membrane; membrane; plasma membrane

Molecular Function: acetylcholine transmembrane transporter activity; dopamine transmembrane transporter activity; norepinephrine transmembrane transporter activity; organic cation transmembrane transporter activity; protein binding; quaternary ammonium group transmembrane transporter activity; secondary active organic cation transmembrane transporter activity

Biological Process: dopamine transport; multidrug transport; neurotransmitter transport; norepinephrine transport; organic cation transport