Holothurin: an activator of bovine brain 3'-5' phosphodiesterase.
The effect of marine toxin, holothurin A, on calmodulin(CaM)-dependent bovine brain 3'-5' phosphodiesterase (PDE) was studied. Holothurin stimulated CaM-depleted PDE in a concentration dependent manner and this interaction was independent of Ca2+ concentrations. Activation of PDE by holothurin was pH and incubation temperature dependent. Heat treatment of holothurin (at 95 degrees C) at various time intervals (2-8 min) decreased its ability to stimulate PDE. CaM-dependent dependent PDE activity was decreased by holothurin. CaM antagonist W-7 and an organochlorine compound chlordecone significantly inhibited holothurin stimulated PDE. These data indicate that holothurin activates CaM-deficient 3'-5' PDE which is antagonized by classical CaM antagonists.
Department of Neurology, University of Mississippi Medical Center, Jackson 39216.
P J
PJ
Vig
B D
BD
Mehrotra
D
D
Desaiah
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000201:enzymology; D002118:Calcium / Q000494:pharmacology; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000502:physiology; D002417:Cattle; D007631:Chlordecone / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D006697:Holothurin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D012503:Saponins / Q000494:pharmacology*; D013449:Sulfonamides / Q000494:pharmacology; D013696:Temperature
D002147:Calmodulin; D012503:Saponins; D013449:Sulfonamides; D006697:Holothurin; C017967:W 7; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D007631:Chlordecone; D002118:Calcium