Ontogenesis and independent genetic control of the rat adenylate kinase isozymes (EC 2.7.4.3.)

The level of activity of cytoplasmic isozyme II of adenylate kinase (EC 2.7.4.3) appears to be genetically controlled in the rat ( Rattus norvegicus). Adult animals of the Okamoto inbred strain exhibit a ninefold higher erythrocytic activity than the rats of the dilute agouti inbred strain. This difference seems to be due to two codominant autosomal alleles at a same locus. The study of the ontogeny of that enzyme in muscle in the two strains shows that the wellknown postnatal activity increase of that isozyme is reduced in the low activity (dilute agouti) strain. However, the mitochondrial isozyme III activity is not similarly regulated as no difference between the two strains has been observed.