Crystal structure of a mammalian phosphoinositide-specific phospholipase Cδ

Mammalian phosphoinositide-specific phospholipase C enzymes (PI-PLC) act as signal transducers that generate two second messengers, inositol-l,4,5-trisphosphate and diacylglycerol. The 2.4-Å structure of phospholipase Cδ1 reveals a multidomain protein incorporating modules shared by many signalling proteins. The structure suggests a mechanism for membrane attachment and Ca 2+ -dependent hydrolysis of second-messenger precursors. The regulation and reversible membrane association of PI-PLC may serve as a model for understanding other multidomain enzymes involved in phospholipid signalling.