Mitochondrial potassium channel located in the mitochondrial inner membrane (PubMed:31435016). Together with ABCB8/MITOSUR, forms a protein complex localized in the mitochondria that mediates ATP-dependent potassium currents across the inner membrane (that is, mitoK(ATP) channel) (PubMed:31435016). May contribute to the homeostatic control of cellular metabolism under stress conditions by regulating the mitochondrial matrix volume (PubMed:31435016). Inhibited by ATP via mitoK(ATP) channel. The mitochondrial potassium channel (mitoK(ATP)) is composed of 4 subunits of CCDC51/MITOK and 4 subunits of ABCB8/MITOSUR. Knockout mice exhibit no visible phenotype (PubMed:31435016). Mutant mice are slightly more sensitive to the ischaemia-reperfusion protocol (PubMed:31435016).