Question

How are the cellular effects of insulin mediated and how does insulin regulate the activity of glycogen phosphorylase?

Answer 1

Exact mechanism of cellular mediated effects are not known.Although translocation and activation of glucose transported protein are some of the insulin mediated effects of cell through RTK pathway, second messenger and protein kinase C.

After eating food insulin gets activated and activates PP -1 which dephosohorylates glycogen phosphorylase a and reforming the inactive glycogen phosphorylase b and Phosphodiesterase which converts cAMP to AMP.cAMP is a secondary messenger but because of the conversion of cAMP to AMP; cAMP is no longer available hence it inhibits the phosohorylation cascade which ends up the formation of active glycogen phosphorylase.