Glucagon
Glucagon — A 29-amino acid peptide hormone produced by pancreatic alpha cells that raises blood glucose levels by promoting glycogenolysis in the liver.
What Is Glucagon?
Glucagon is a 29-amino acid peptide hormone (molecular weight: 3482.8 Da) produced by pancreatic alpha cells. It is the primary counter-regulatory hormone to insulin, raising blood glucose by stimulating hepatic glycogenolysis and gluconeogenesis. Glucagon and insulin work in opposing balance to maintain glucose homeostasis.
Mechanism of Action
Glucagon binds the glucagon receptor (GCGR), a class B GPCR that activates Gs/adenylyl cyclase/cAMP/PKA signaling in hepatocytes. PKA phosphorylates glycogen phosphorylase (activating glycogen breakdown) and glycogen synthase (inhibiting glycogen synthesis), rapidly mobilizing glucose from liver stores.
Research Applications
- Diabetes: GLP-1/glucagon dual agonists (survodutide) are in clinical trials for obesity and NASH
- Hypoglycemia rescue: Injectable and nasal glucagon are FDA-approved emergency treatments
- Structural biology: Glucagon forms amyloid fibrils readily, making it a model for aggregation studies
Frequently Asked Questions
What is Glucagon?
A 29-amino acid peptide hormone produced by pancreatic alpha cells that raises blood glucose levels by promoting glycogenolysis in the liver.
Why is Glucagon important in peptide research?
Glucagon is a fundamental concept in compound as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.