Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene 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, can form heterodimers with two other inward-rectifier type potassium channels. It may be involved in the regulation of fluid and pH balance. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2012]