Question

Sort the following into activators or inhibitors of glycogen synthase. Items (6 items) (Drag and drop into the appropriate area below) Epinephrine Insulin Glycogen synthase kinase 3 Protein kinase A (PKA) Protein phosphatase 1 Glucagon Categories Activators Inhibitors Drag and drop here Drag and drop here

Answer 1

Glycogen synthase kinase 3 inhibits the glycogen synthesis by phosphorylation of glycogen synthase enzyme.

epinephrine also promotes increased glucose level in the body hence preventing the action of glycogen synthase to make glycogen.

protein kinase also inhibits glycogen synthesis by phosphorylating glycogen synthase enzyme at its serine or threonine residue

Insulin promote low glucose level in the blood by directing liver cells to convert glucose into glycogen so it activates glycogen synthase.

protein phosphatase 1 helps in dephosphorylating the glycogen synthase which is done by protein kinase A and other group of kinases. Hence promote glycogen synthase

Glucagon promotes glycogen breakdown in the liver to increase the glucose level in the blood hence it inhibits the glycogen synthase enzyme.

So the activators are- insulin, protein phosphatase 1

The inhibitor are- gsk3, epinephrine, glucagon, protein kinase A