Given that enhanced COUP-TFII expression led to a repression of mitochondrial ribosome genes, and that several mitochondrial ribosome genes are mapped to loci associated with mitochondrial diseases arising from impaired oxidative phosphorylation [48], our studies suggest that COUP-TFII contributes to mitochondrial dysfunction in PD. This evidence concerns the gene NR2F2 and inborn mitochondrial metabolism disorder.