Stimulus-induced phosphorylation of vacuolar H(+)-ATPase by protein kinase A.

摘要: Eukaryotic vacuolar-type H+-ATPases (V-ATPases) are regulated by the reversible disassembly of active V1V0 holoenzyme into a cytosolic V1 complex and membrane-bound V0 complex. The signaling cascades that trigger these events in response to changing cellular conditions largely unknown. We report subunit C tobacco hornworm Manduca sexta interacts with protein kinase A is only V-ATPase phosphorylated A. Subunit can be as single polypeptide well part but not holoenzyme. Both unphosphorylated form able reassociate from which had been removed before. Using salivary glands blowfly Calliphora vicina reassembly activity neurohormone serotonin via A, we show membrane-permeable cAMP analog 8-(4-chlorophenylthio)adenosine-3′,5′-cyclic monophosphate (8-CPT-cAMP) causes phosphorylation tissue homogenate reduced incubation antibodies against C. Similarly, intact 8-CPT-cAMP or leads C, this abolished H-89, an inhibitor These data suggest binds serves substrate for may regulatory switch formation