Extraneuronal Monoamine Transporter (EMT)

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. SLC22A3 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.

The SLC22A3 gene encodes a deduced 556-amino acid protein containing 12 transmembrane segments. Expression analysis showed uptake of known catecholamine substrates by SLC22A3. RT-PCR analysis detected SLC22A3 expression in brain cortex, heart, and liver.