Aliases for KCNJ3 Gene
External Ids for KCNJ3 Gene
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, is controlled by G-proteins and plays an important role in regulating heartbeat. It associates with three other G-protein-activated potassium channels to form a heteromultimeric pore-forming complex that also couples to neurotransmitter receptors in the brain and whereby channel activation can inhibit action potential firing by hyperpolarizing the plasma membrane. These multimeric G-protein-gated inwardly-rectifying potassium (GIRK) channels may play a role in the pathophysiology of epilepsy, addiction, Down's syndrome, ataxia, and Parkinson's disease. Alternative splicing results in multiple transcript variants encoding distinct proteins. [provided by RefSeq, May 2012]
GeneCards Summary for KCNJ3 Gene
KCNJ3 (Potassium Channel, Inwardly Rectifying Subfamily J, Member 3) is a Protein Coding gene. Diseases associated with KCNJ3 include pancreas adenocarcinoma. Among its related pathways are G-Beta Gamma Signaling and G Protein Signaling Pathways. GO annotations related to this gene include inward rectifier potassium channel activity and G-protein activated inward rectifier potassium channel activity. An important paralog of this gene is KCNJ5.
UniProtKB/Swiss-Prot for KCNJ3 Gene
This potassium channel is controlled by G proteins. Inward rectifier potassium channels are characterized by a greater tendency to allow potassium to flow into the cell rather than out of it. Their voltage dependence is regulated by the concentration of extracellular potassium; as external potassium is raised, the voltage range of the channel opening shifts to more positive voltages. The inward rectification is mainly due to the blockage of outward current by internal magnesium. This receptor plays a crucial role in regulating the heartbeat
The inward-rectifier potassium channel family (also known as 2-TM channels) include the strong inward-rectifier channels (KIR2.x), the G-protein-activated inward-rectifier channels (KIR3.x) and the ATP-sensitive channels (KIR6.x, which combine with sulphonylurea receptors (SUR)). Structurally, the pore-forming subunit of KIR channels is the alpha-subunit. It contains a single pore domain between two membrane spanning regions. Four alpha-subunits combine to form a tetramer, with the pore domain of each subunit contributing to the structure of the central pore. Heteromeric channels can also be formed within subfamilies, e.g. KIR3.2 with KIR3.3.