Emc. Skoulakis et al., PREFERENTIAL EXPRESSION IN MUSHROOM BODIES OF THE CATALYTIC SUBUNIT OF PROTEIN KINASE-A AND ITS ROLE IN LEARNING AND MEMORY, Neuron, 11(2), 1993, pp. 197-208
Involvement of the cAMP cascade in Drosophila learning and memory is s
uggested by the aberrant behavioral phenotypes of the mutants dunce (c
AMP phosphodiesterase) and rutabaga (adenylyl cyclase). Line DCO581, i
solated via an enhancer detector screen for genes preferentially expre
ssed in the mushroom bodies, contains a transposon in the first exon o
f the catalytic subunit gene (DCO) of protein kinase A (PKA). RNA in s
itu hybridization and immunohistochemistry show that DCO is preferenti
ally expressed in the mushroom bodies. The DCO581 insertion and an ind
ependently isolated hypomorphic allele (DCO(B10)) each produce homozyg
ous lethality and a 40% decrease in PKA activity in heterozygotes. Thi
s decrease has mild effects on learning but no effect on memory. Howev
er, the 80% reduction in activity obtained by constructing heteroallel
ic yet viable DCO581/DCO(B10) animals results in a dramatic learning a
nd memory deficit. These results suggest that PKA plays a crucial role
in the cAMP cascade in mushroom bodies to mediate learning and memory
processes.