Isozymes delta of phosphoinositide-specific phospholipase C

Phospholipase C (PLC, EC 3.1.4.11) is the major starting point in the phosphatidylinositol pathway, which generates intracellular signals that regulate protein kinase C and intracellular calcium concentration. To date, three major types of phosphoinositide-specific PLC species named β, γ and δ, have been characterized. This article reviews recent studies on isozymes delta of PLC. Four such isozymes have been cloned and termed δ1-4. Their structural organization, regulation of activity and the interaction with membrane lipid are considered. The intracellular localization of delta isozymes and distribution in various tissues are presented. Attention is given to the pathological conditions in which an abnormal protein level of PLC d or its activity have been observed.