1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase beta-4 is a protein in humans that is encoded by PLCB4 gene. 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 form has a role in retina signal transduction.