Regulation of ROMK (Kir1.1) channels: new mechanisms and aspects.
This brief review attempts to provide an overview regarding recent developments in the regulation of ROMK channels. Studies performed in ROMK null mice suggest that ROMK cannot only form hometetramers such as the small-conductance (30-pS) K channels but also construct heterotetramers such as the 70-pS K channel in the thick ascending limb (TAL). The expression of ROMK channels in the plasma membrane is regulated by protein tyrosine kinase (PTK), serum and glucorticoid-induced kinase (SGK), and with-no-lysine-kinase 4. PTK is involved in mediating the effect of low K intake on ROMK channel activity. Increases in superoxide anions induced by low dietary K intake are responsible for the stimulation of PTK expression and tyrosine phosphorylation of ROMK channels. Finally, a recent study indicated that ROMK channels can be monoubiquitinated and monoubiquitination regulates the surface expression of ROMK channels.
Wang
Wen-Hui
WH
Dept. of Pharmacology, New York Medical College, Valhalla, NY 10595, USA. wenhui_wang@nym.edu
D000818:Animals; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000502:physiology; D007668:Kidney / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008954:Models, Biological; D015221:Potassium Channels / Q000378:metabolism*; D024661:Potassium Channels, Inwardly Rectifying / Q000378:metabolism*; D021381:Protein Transport; D011505:Protein-Tyrosine Kinases / Q000502:physiology; D051381:Rats; D013481:Superoxides / Q000378:metabolism; D025801:Ubiquitin / Q000502:physiology
C510693:Kcnj1 protein, mouse; C510692:Kcnj1 protein, rat; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D025801:Ubiquitin; D013481:Superoxides; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D011505:Protein-Tyrosine Kinases