PubMed 10764726

Title: pH dependence of the inwardly rectifying potassium channel, Kir5.1, and localization in renal tubular epithelia.

Authors: S J Tucker, P Imbrici, L Salvatore, M C D'Adamo, M Pessia

Journal, date & volume: J. Biol. Chem., 2000 Jun 2 , 275, 16404-7

PubMed link:

The physiological role of the inwardly rectifying potassium channel, Kir5.1, is poorly understood, as is the molecular identity of many renal potassium channels. In this study we have used Kir5.1-specific antibodies to reveal abundant expression of Kir5.1 in renal tubular epithelial cells, where Kir4.1 is also expressed. Moreover, we also show that Kir5.1/Kir4.1 heteromeric channel activity is extremely sensitive to inhibition by intracellular acidification and that this novel property is conferred predominantly by the Kir5.1 subunit. These findings suggest that Kir5.1/Kir4.1 heteromeric channels are likely to exist in vivo and implicate an important and novel functional role for the Kir5.1 subunit.