Negative feedback regulation of Gq signaling by protein kinase C is disrupted by diacylglycerol kinase ζ in COS-7 cells

► Protein kinase C (PKC) is implicated in negative regulation of Gq signaling. ► Diacylglycerol kinases (DGKs) metabolize diacylglycerol to limit PKC activity. ► Cell-specific patterns of regulation alter DGK activity. ► DGKζ is shown to terminate negative feedback regulation by PKC in COS-7 cells. ► Cell-specific patterns of regulation determine response.