Glucagon receptor (GCGR)

G-protein coupled receptor for glucagon that plays a central role in the regulation of blood sugar levels and glucose homeostasis. Regulates the rate of hepatic glucose production by promoting glycogen hydrolysis and gluconeogenesis.

Plays an important role in mediating the responses to fasting. Ligand binding causes a conformation change that triggers signaling through guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase.