Thymidine kinase activity is reduced in the developing staggerer cerebellum.

In the mouse cerebellar mutant staggerer, thymidine kinase levels do not increase developmentally at ages when the wild-type level is high. Mixing experiments show that this effect is not due to an endogenous inhibitor of the enzyme. Both the Km and the susceptibility of the thymidine kinase to nucleotide inhibitors are unaltered in the mutant animals, suggesting that the enzyme is not induced in the mutant.