Hemoxygenase-2 is an oxygen sensor for a calcium-sensitive potassium channel
SEJ Williams, P Wootton, HS Mason, J Bould, DE Iles… - Science, 2004 - science.org
SEJ Williams, P Wootton, HS Mason, J Bould, DE Iles, D Riccardi, C Peers, PJ Kemp
Science, 2004•science.orgModulation of calcium-sensitive potassium (BK) channels by oxygen is important in several
mammalian tissues, and in the carotid body it is crucial to respiratory control. However, the
identity of the oxygen sensor remains unknown. We demonstrate that hemoxygenase-2 (HO-
2) is part of the BK channel complex and enhances channel activity in normoxia. Knockdown
of HO-2 expression reduced channel activity, and carbon monoxide, a product of HO-2
activity, rescued this loss of function. Inhibition of BK channels by hypoxia was dependent on …
mammalian tissues, and in the carotid body it is crucial to respiratory control. However, the
identity of the oxygen sensor remains unknown. We demonstrate that hemoxygenase-2 (HO-
2) is part of the BK channel complex and enhances channel activity in normoxia. Knockdown
of HO-2 expression reduced channel activity, and carbon monoxide, a product of HO-2
activity, rescued this loss of function. Inhibition of BK channels by hypoxia was dependent on …
Modulation of calcium-sensitive potassium (BK) channels by oxygen is important in several mammalian tissues, and in the carotid body it is crucial to respiratory control. However, the identity of the oxygen sensor remains unknown. We demonstrate that hemoxygenase-2 (HO-2) is part of the BK channel complex and enhances channel activity in normoxia. Knockdown of HO-2 expression reduced channel activity, and carbon monoxide, a product of HO-2 activity, rescued this loss of function. Inhibition of BK channels by hypoxia was dependent on HO-2 expression and was augmented by HO-2 stimulation. Furthermore, carotid body cells demonstrated HO-2–dependent hypoxic BK channel inhibition, which indicates that HO-2 is an oxygen sensor that controls channel activity during oxygen deprivation.
AAAS