[Cyclic nucleotide phosphodiesterases in mutant lines of Drosophila melanogaster]

The activities of general phosphodiesterase and its Ca(2+)-calmodulin-independent from (PDE-1) were studied in strains mutant for the agnostic gene and in the strain Canton S. Enzyme activity was determined in males and homo- and hemizygous females of four strains. It was found that mutation at the agnostic gene resulted in increased PDE-1 activity. This effect appears to depend on the dose of the mutant gene, because it was revealed only in homozygous females. We have substantiated the notion that the agnostic gene controls calmodulin properties by virtue of encoding a calmodulin-inhibiting protein.