ATP synthase membrane subunit K (ATPMK, also known as DAPIT) is a subunit of mitochondrial ATP synthase that produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain [, ]. In humans ATP5MD (also known as DAPIT) is a minor subunit of the mitochondrial membrane ATP synthase required for dimerization of the ATP synthase complex and as such regulates ATP synthesis in the mitochondria [, ].Mutations of the ATP5MD gene cause mitochondrial complex V deficiency, nuclear type 6 (MC5DN6), an autosomal recessive mitochondrial disorder characterized by gross motor developmental delay manifesting in the first years of life, and subsequent episodic developmental regression [].
