ATPase inhibitor, mitochondrial (Atp5if1)

Endogenous F(1)F(o)-ATPase inhibitor limiting ATP depletion when the mitochondrial membrane potential falls below a threshold and the F(1)F(o)-ATP synthase starts hydrolyzing ATP to pump protons out of the mitochondrial matrix. Required to prevent the consumption of cellular ATP when the F(1)F(o)-ATP synthase enzyme functions as an ATP hydrolase.

Indirectly functions as a regulator of heme synthesis in erythroid cells: regulates heme synthesis by modulating the mitochondrial pH and redox potential, allowing FECH to effectively catalyze the incorporation of iron into protoporphyrin IX to create heme (By similarity). .