ROMK

The renal outer medullary potassium channel (ROMK) is an ATP-dependent is_associated_with::potassium channel (Kir1.1) that transports potassium out of cells. It plays an important role in potassium recycling in the is_associated_with::thick ascending limb (TAL) and potassium is_associated_with::secretion in the is_associated_with::cortical collecting duct (CCD) of the is_associated_with::nephron. In humans, ROMK is encoded by the KCNJ1 (potassium inwardly-rectifying channel, subfamily J, member 1) is_associated_with::gene. Multiple transcript variants encoding different isoforms have been found for this gene.

Function
is_associated_with::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. It is inhibited by internal ATP and probably plays an important role in potassium homeostasis. The encoded protein has a greater tendency to allow potassium to flow into a cell rather than out of a cell (hence the term "inwardly rectifying"). ROMK was identified as the pore forming component of mitoKATP channels that are known to have a critical role during stroke or other ischemic attacks in the protection against hypoxia-induced brain injury.

Clinical significance
Mutations in this gene have been associated with antenatal is_associated_with::Bartter syndrome, which is characterized by salt wasting, hypokalemic alkalosis, hypercalciuria, and low blood pressure.