Subunits I and II of Dictyostelium cytochrome c oxidase are specified by a single open reading frame transcribed into a large polycistronic RNA.

A single open reading frame (ORF) encoding cytochrome c oxidase subunit I and II (cox1/2) was identified in the mitochondrial genome of the slime mold Dictyostelium discoideum. The cox1 coding region shares intron positions with its counterparts in fungi and algae. Northern blot analysis, using exon and intron-specific probes, suggests that the cox1/2 gene is transcribed as part of a large, efficiently processed, polycistronic RNA.