An organic cation transport protein mediates the transport of organic cations across the cell membrane. These proteins are members of the solute carrier family, subfamily 22. This family of proteins can also transport zwitterions and anions, though it is a different subfamily of solute carrier proteins than the organic anion transporters.
| Abbreviation | Protein name | Location | Transported solute(s) | Associated disorder(s) |
|---|---|---|---|---|
| SLC22A1 | Solute carrier family 22 member 1 | Liver, brain (cerebellum) | ||
| SLC22A2 | Solute carrier family 22 member 2 | Primarily in kidney, also in brain | ||
| SLC22A3 | Solute carrier family 22 member 3 | Brain and kidney | Histamine, dopamine, serotonin, norepinephrine, MPP+ | |
| SLC22A4 | Solute carrier family 22 member 4 | Sodium ion and ergothioneine | ||
| SLC22A5 | Solute carrier family 22 member 5 | Primary carnitine deficiency | ||
| SLC22A6 | Solute carrier family 22 member 6 | |||
| SLC22A7 | Solute carrier family 22 member 7 | |||
| SLC22A8 | Solute carrier family 22 member 8 | |||
| SLC22A9 | Solute carrier family 22 member 9 | |||
| SLC22A10 | Solute carrier family 22 member 10 | |||
| SLC22A11 | Solute carrier family 22 member 11 | |||
| SLC22A12 | Solute carrier family 22 member 12 | Kidney | Uric acid | Hyperuricemia and hypouricemia |
| SLC22A13 | Solute carrier family 22 member 13 | |||
| SLC22A14 | Solute carrier family 22 member 14 | |||
| SLC22A15 | Solute carrier family 22 member 15 | |||
| SLC22A16 | Solute carrier family 22 member 16 | |||
| SLC22A17 | Solute carrier family 22 member 17 | |||
| SLC22A18 | Solute carrier family 22 member 18 | Beckwith-Wiedemann syndrome, Wilms tumor, rhabdomyosarcoma, adrenocortical carcinoma, and lung, ovarian, and breast cancer | ||
| SLC22A19 | Solute carrier family 22 member 19 | |||
| SLC22A20 | Solute carrier family 22 member 20 |