Potassium Inwardly Rectifying Channel Subfamily J, Member 9 (KCNJ9)

KCNJ9 is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, is controlled by G-proteins. It associates with another G-protein-activated potassium channel to form a heteromultimeric pore-forming complex.

Lesage et al. (1994) reported the cloning of a G-protein coupled inward rectifier potassium channel from the mouse which they designated mbGIRK3. Like other members of the family, the predicted 376-amino acid protein contains 2 hydrophobic membrane-spanning domains and a pore-forming domain. It is about 65% identical to IRK1 and 50% with ROMK1 and GIRK1. Highest expression was found in the brain.