Gq protein-coupled pathway (Gq pathway)

The Gq protein-coupled pathway is a major intracellular signaling cascade activated by specific G protein-coupled receptors (GPCRs) expressed on the surface of pancreatic islet cells, particularly β cells. This pathway plays a crucial role in regulating hormone secretion, especially insulin, and thus contributes to glucose homeostasis. Key receptors include muscarinic acetylcholine receptor M3, FFAR1/GPR40, and P2Y receptors. Activation leads to PLCβ activation, IP3 and DAG production, increased intracellular calcium, PKC activation, and ultimately enhanced insulin secretion. Dysregulation can contribute to impaired glucose homeostasis and diabetes mellitus development.

Other names

Gq/11 signaling pathwayPLCβ pathway in pancreatic isletsMuscarinic acetylcholine receptor M3 signaling pathwayFFAR1/GPR40 signaling pathwayP2Y receptor signaling pathway

Activation of phospholipase C beta (PLCβ), leading to the generation of inositol trisphosphate (IP3) and diacylglycerol (DAG). IP3 mobilizes calcium from intracellular stores, increasing cytosolic Ca²⁺ concentration. DAG activates protein kinase C (PKC). Elevated Ca²⁺ and PKC activity promote exocytosis of insulin-containing granules from β cells.