P13807 

Glycogen synthase 1(GYS1) belongs to the mammalian/fungal glycogen synthase family of proteins. Glycogen synthase 1 plays a crucial role in glycogen biosynthesis, transferring glycosyl residues from UDP-Glucose to the nonreducing end of α-1,4-glucan, which is essential for energy storage in cells. This protein exists in two forms: a liver variant and a muscle variant, each tailored to meet the metabolic demands of their respective tissues. The liver form helps maintain blood glucose homeostasis, responding to nutritional signals to regulate glucose levels in the bloodstream, while the muscle form activates during physical activity, providing energy for muscle contraction. Mutations in the gene encoding liver glycogen synthase can lead to glycogen storage disease type 0 (GSD0), a condition characterized by fasting hypoglycemia and impaired glycogen synthesis, highlighting glycogen synthase 1′s significance in metabolic health.