The activity of glycogen synthase is regulated by several mechanisms, including phosphorylation and allosteric regulation. Phosphorylation by protein kinases generally inactivates the enzyme, while dephosphorylation by phosphatases activates it. Additionally, the enzyme is allosterically activated by glucose-6-phosphate, a key intermediate in carbohydrate metabolism. Hormonal regulation is also crucial, with insulin promoting glycogen synthesis and glucagon and epinephrine inhibiting it.
