Potassium Inwardly Rectifying Channel Subfamily J, Member 5 (KCNJ5)

KCNJ5 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 may associate with two other G-protein-activated potassium channels to form a heteromultimeric pore-forming complex. Girk4 associated with Girk1 during or shortly after subunit synthesis and allowed appropriate glycosylation of the Girk1 subunit to a form seen in native atrial tissue. The C terminus of Girk4 was required for cell surface localization. Girk1 appeared intracellular in atrial myocytes isolated from Girk4-knockout mice, and it was not maturely glycosylated, supporting an essential role for GIRK4 in processing and cell surface localization of GIRK1/GIRK4 channels in vivo.