Cytochrome C Oxidase Assembly Protein 19 (COX19)

COX19 encodes a cytochrome c oxidase (COX)-assembly protein. The S. cerevisiae Cox19 protein may play a role in metal transport to the mitochondrial intermembrane space and assembly of complex IV of the mitochondrial respiratory chain.

The deduced 90-amino acid protein has a predicted molecular mass of about 10.4 kD. COX19 is a hydrophilic protein and shares 4 conserved cysteine residues with COX17. Northern blot analysis detected 3.6-kb, 4.6-kb, and 6.0-kb transcripts in all tissues examined with highest expression in skeletal muscle. RACE analysis identified a transcript of 3,602 nucleotides. Fluorescence microscopy showed that COX19 expressed in HEK293 cells had a diffuse cytosolic localization.