Proteolytic activation can produce a phosphatidylinositol phosphodiesterase highly sensitive to Ca2+.
The phosphatidylinositol phosphodiesterase of rat brain shows little activity under conditions likely to pertain in vivo (neutral pH and micromolar Ca(2+) concentrations). A short incubation of a brain supernatant with trypsin, or a longer pre-incubation of the supernatant alone, produce new forms of the enzyme, which are active under such conditions. A possible role of receptor-linked proteinases in initiating phosphatidylinositol catabolism is discussed.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology*; D002118:Calcium / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D066298:In Vitro Techniques; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D051381:Rats; D014357:Trypsin / Q000494:pharmacology
D010727:Phosphoric Diester Hydrolases; D014357:Trypsin; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D002118:Calcium