Cytochrome c oxidase (COX) is one of only four bigenomic proteins in mammalian cells,
having ten subunits encoded in the nuclear genome and three in the mitochondrial DNA.
The mechanism of its bigenomic control is not well understood. The ten nuclear subunits are
on different chromosomes, and the possibility of their coordinate regulation by the same
transcription factor (s) deserves serious consideration. The present study tested our
hypothesis that nuclear respiratory factor 1 (NRF-1) serves such a role in subunit …