The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes. This protein may be involved in the transduction of bitter taste stimuli. a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-4,5-bisphosphate) + H2O = 1D-myo-inositol 1,4,5-trisphosphate + a 1,2-diacyl-sn-glycerol + H(+) a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol) + H2O = 1D-myo-inositol 1-phosphate + a 1,2-diacyl-sn-glycerol + H(+) Binds 1 Ca(2+) ion per subunit. Interacts with RAC1 (By similarity). Forms a complex composed of at least WDR26, a G-beta:gamma unit, and PLCB2 (By similarity). A number of isoforms may be produced. Expressed in the gustatory cells of the circumvallate papillae. Not detected in non-sensory lingual epithelium, brain, parotid gland, liver, uterus, lung, heart, adrenal gland, ovary, spleen, pancreas, intestine, thymus, kidney or muscle. The receptor-mediated activation of PLC-beta-2 is most effectively mediated by one G-protein alpha subunit, alpha-16.