DOWN-REGULATION OF MITOCHONDRIAL MESSENGER-RNAS IN THE MDX MOUSE MODEL FOR DUCHENNE MUSCULAR-DYSTROPHY

In our search for genes up- or down-regulated genes in the mdx mouse m odel for Duchenne muscular dystrophy, me isolated a down-regulated mit ochondrial DNA clone, In addition to this clone, all protein-coding mi tochondrial genes tested had tissue-specific and age independent down- regulated expression. This implied mechanisms at the RNA level since n o change in the mitochondrial DNA contents were detected. Cytochrome c oxidase activity shelved the same range of down-regulated expression. These data provide a molecular basis for energetic metabolism modific ations in mdx mice.