Which one of the following directly results in the activation of glycogen synthase?
A)Binding of glucose-6-phosphate
B)Dephosphorylation of multiple residues by phosphoprotein phosphorylase-1 (PP1)
C)Phosphorylation of specific residues by casein kinase II (CKII)
D)Phosphorylation of specific residues by glycogen synthase kinase-3 (GSK-3)
E)The presence of insulin

Question

Quizplus · Accepted Answer

The activation of glycogen synthase involves the dephosphorylation of multiple residues by phosphoprotein phosphatase-1 (PP1). Glycogen synthase is inactivated by phosphorylation by GSK-3, CKII and other kinases. The binding of glucose-6-phosphate and the presence of insulin indirectly activate glycogen synthase by promoting the dephosphorylation of glycogen synthase through the activation of PP1. However, they do not directly activate glycogen synthase.

Which One of the Following Directly Results in the Activation