Hepatic enzyme undergoes phosphorylation from dephosphorvlated state. Which of the following is true: (A) Affected by level of Catecholamines, (B) Occurs in starvation rather than well fed state, (C) Always activated by c-AMP dependent protein kinase, (D) Always activates the enzyme
Answer is C. Ans. c. Always activated by c-AMP dependent protein kinaseEpinephrine and norepinephrine (in muscle during activity) or glucagon (in liver when blood glucose level is too low) increase concentration of c-AMP, which inturn activates c-AMP dependent protein kinase (protein kinase a or PICA).Allosteric Control of Phosphorylase occurs throughIn MuscleActivation: Ca2+degc-AMPdeg5'-AMP Inhibition: - ATPdegGlucose-6-phosphateIn LiverActivation: - c-AMPdegInhibition:ATPdegGlucose-6-phosphate Free glucosedeg