Figure 1.

The early assembly of cytochrome c oxidase. Assembly of COX begins with translation of mitochondrial RNA with mitochondrial ribosomes and proceeds in a series of intermediates. The inner mitochondrial membrane is shown in conjunction with the partially assembled enzyme intermediates, with the bottom region denoting the matrix side. TACO1, which is involved in RNA binding, is shown in green, assembly factors are in blue, and mitochondrial-encoded subunits (COX I, COX II, and COX III) are in yellow. Nuclear subunits are indicated in orange, with isoforms grouped and denoted with a striped pattern in light orange.