Potassium channel protein subunit Kir6.2 (Kir6.2)

Potassium channel protein subunit Kir6.2 is a pore-forming component of ATP-sensitive potassium (KATP) channels, primarily encoded by the gene KCNJ11. These channels are hetero-octameric complexes composed of four central Kir6.2 subunits surrounded by four regulatory sulfonylurea receptor 1 (SUR1) units; together they play a crucial role in linking cellular metabolism with electrical excitability across various tissues, most notably pancreatic β-cells where they regulate insulin secretion in response to blood glucose levels. Mutations in Kir6.2 can lead either to congenital hyperinsulinism or permanent neonatal diabetes mellitus depending on whether they increase or decrease sensitivity to ATP inhibition respectively; some mutations are also associated with neurological symptoms when affecting neuronal isoforms. Drugs such as glibenclamide act as pharmacochaperones or inhibitors by binding within SUR1 but stabilizing interactions critical for proper assembly and function involving both SUR and Kir components—ultimately modulating ion flow through this essential metabolic sensor complex.

Other names

ATP-sensitive inward rectifier potassium channel 11KCNJ11 (gene name)Inward rectifier potassium channel Kir6.2KATP channel subunit Kir6.2

Channel inhibition by sulfonylureas and related drugs, which bind the regulatory SUR subunit but affect the function of the Kir6.2 pore-forming unit, leading to closure of the KATP channels and stimulation of insulin secretion from pancreatic β-cells.