SLC22A6 is involved in the sodium-dependent transport and excretion of organic anions, some of which are potentially toxic. The encoded protein is an integral membrane protein and may be localized to the basolateral membrane. Five transcript variants encoding five different isoforms have been found for this gene.The deduced 550-amino acid protein contains 12 transmembrane spans, 4 protein kinase C phosphorylation sites, 4 protein kinase A phosphorylation sites, and 5 putative N-glycosylation sites. SLC22A6 shares 87% identity with rat Oat1, 85% identity with mouse Oat1, and 32% and 29% identity with the cation transporters OCT1 (SLC22A1) and OCTN2 (SLC22A5), respectively. Northern blot analysis of several tissues detected a 2.4-kb transcript only in kidney.