MitoBK_Ca channel is functionally associated with its regulatory β1 subunit in cardiac mitochondria.

ABSTRACT:

Key points

Association of plasma membrane BK_Ca channels with BK-β subunits shapes their biophysical properties and physiological roles; however, functional modulation of the mitochondrial BK_Ca channel (mitoBK_Ca ) by BK-β subunits is not established. MitoBK_Ca -α and the regulatory BK-β1 subunit associate in mouse cardiac mitochondria. A large fraction of mitoBK_Ca display properties similar to that of plasma membrane BK_Ca when associated with BK-β1 (left-shifted voltage dependence of activation, V_1/2  = -55 mV, 12 µm matrix Ca²⁺ ). In BK-β1 knockout mice, cardiac mitoBK_Ca displayed a low P_o and a depolarized V_1/2 of activation (+47 mV at 12 µm matrix Ca²⁺

SUBMITTER: Balderas E 

PROVIDER: S-EPMC6690848 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature