KCNJ5

KCNJ5 also known as Potassium Voltage-Gated Channel Subfamily J Member 5 is a protein that in humans is encoded by the KCNJ5 gene. KCNJ5 is a member of the G protein-coupled inwardly rectifying potassium channel (GIRK) family, also known as Kir3 family, a type of potassium channel.

Function

KCNJ5 is a G protein-activated inward rectifier potassium channel. 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. KCNJ5 is activated via G protein-coupled receptors, such as the GABA-B receptor.

Clinical significance

Mutations in the KCNJ5 gene have been associated with primary aldosteronism, a condition characterized by the overproduction of the hormone aldosterone. This overproduction can lead to a variety of symptoms, including high blood pressure, muscle weakness, and sometimes even paralysis.

See also

• Inward-rectifier potassium ion channels
• G protein-coupled inwardly rectifying potassium channel

External links

• KCNJ5 at the National Center for Biotechnology Information