Cyclic AMP-induced phosphorylation of 27.5-kDa protein(s) in larval brains of normal and memory-mutant Drosophila melanogaster.
Whole brains dissected from third-instar larvae of Drosophila melanogaster increase their cAMP content when incubated with octopamine, dopamine and serotonin, especially in the presence of theophylline, a phosphodiesterase inhibitor. The most pronounced rise in cAMP was produced by forskolin. When brains prelabelled with [32P]orthophosphate were subjected to these treatments, the increased labelling of 27.5-kDa protein(s) of pI 6.3-6.6 (substrate A) was observed in all cases, as revealed by two-dimensional gel electrophoresis and autoradiography. Labelling of substrate A was enhanced without any drug addition in brains of the dunceM11 mutant strain, which has abnormally high basal cAMP levels. The labelling of substrate A was also promoted by the potassium channel blocker 4-aminopyridine. The data suggest that in Drosophila larval brain the 27.5-kDa protein is a target of cAMP-triggered phosphorylation and may be related to potassium channel(s).
Dévay
P
P
Institute of Enzymology, Hungarian Academy of Sciences, Budapest.
Friedrich
P
P
D000818:Animals; D001921:Brain / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D007700:Kinetics; D007814:Larva; D008568:Memory; D008970:Molecular Weight; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010766:Phosphorylation; D013806:Theophylline / Q000494:pharmacology
D009419:Nerve Tissue Proteins; D005576:Colforsin; D013806:Theophylline; D000242:Cyclic AMP