Potassium Inwardly Rectifying Channel Subfamily J, Member 2 (KCNJ2)

KCNJ2 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, probably participates in establishing action potential waveform and excitability of neuronal and muscle tissues. Mutations in this gene have been associated with Andersen syndrome, which is characterized by periodic paralysis, cardiac arrhythmias, and dysmorphic features. The cDNA encodes a 427-amino acid protein with 2 putative transmembrane domains and an H5 region. Expression of HHIRK1 in Xenopus oocytes demonstrated strong inward rectification that was blocked by both extracellular barium and cesium ions, and they measured a single channel conductance of 30 pS.