SLC25A4

The protein functions as a gated pore in the inner mitochondrial membrane that translocates ADP from the cytoplasm into the mitochondrial matrix and ATP from the mitochondrial matrix into the cytoplasm, forming a homodimer essential for cellular energy metabolism. Mutations cause mitochondrial DNA depletion syndrome with cardiomyopathy (both autosomal dominant and recessive forms) and autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions. The disease mechanism can vary by variant type, with some mutations likely acting through dominant-negative effects that disrupt the homodimer function.