Glycogen Synthase 2, Liver (GYS2)

Glycogen synthase (UDP-glucose-glycogen glucosyltransferase') is a glycosyltransferase enzyme (EC 2.4.1.11) that catalyses the reaction of UDP-glucose and (1,4-α-D-glucosyl)_n to yield UDP and (1,4-α-D-glucosyl)_n+1.Its presence in the bloodstream is highest in the 30 to 60 minutes following intense exercise. It is a key enzyme in glycogenesis.

The liver Glycogen Synthase 2 expression is restricted to the liver, whereas the muscle enzyme is widely expressed. Liver glycogen serves as a storage pool to maintain the blood glucose level during fasting, whereas muscle glycogen synthesis accounts for disposal of up to 90% of ingested glucose. The role of muscle glycogen is as a reserve to provide energy during bursts of activity.