Abnormal activity of adenylate cyclase in the Drosophila memory mutant rutabaga.

The activity of adenylate cyclase in homogenates prepared from the Drosophila memory mutant rutabaga is lower than normal. The effect is most pronounced in washed membranes prepared from the abdomen, in which the enzyme displays both a lower Vmax and a higher Km. Analysis of the effect of divalent cations suggests a lesion in the responsiveness of the enzyme to Mg2+. Studies of adenylate cyclase in rutabaga may potentially pinpoint a subpopulation of the enzyme which may prove relevant to molecular mechanisms underlying conditioning.