Phosphatidylinositol-specific phospholipase C (PLC) enzymes mediate the production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). plc-1 is a bifunctional enzyme; in addition to its role in DAG and IP3 production, it also regulates small GTPases of the Ras superfamily through its Ras guanine-exchange factor (RasGEF) activity. plc-1's production of IP3, acting via the IP3 receptor itr-1, regulates intracellular Ca2+ release. This, in turn, controls the contraction and/or dilation of the distal spermatheca valve during oocyte entry and the timing of spermatheca-uterine valve dilation during oocyte exit, thereby regulating ovulation. Similarly, plc-1 plays a critical role in epidermal morphogenesis by modulating epidermal cell migration during ventral closure and, to a lesser extent, dorsal intercalation. Furthermore, plc-1 is involved in the immune response to Staphylococcus aureus by activating kinase dkf-1 (via DAG production), which subsequently activates the transcription factor hlh-30. In ASER neurons, plc-1 is necessary for adjusting orientation behavior in salt gradients based on memory of previously encountered salt concentrations.
The role of plc-1 in these processes is supported by the following research: