Now these insulin receptorsubstrate molecules in their active form they basically follow a series of steps that ultimately helps activate protein kinases into the active form. So this is basically the insulin signal transduction pathway and once these protein kinases are activated they go on to stimulate target enzyme and target proteins. And in this particular case these protein kinases go on to inactivate glycogen synthase kinase into the inactive form. So by phosphorylating the glycogen synthase kinase these protein kinases basically inactivate the glycogen synthase kinase. Now let's remember what the purpose of glycogen synthase kinase is. So in their active form the glycogen synthase kinase molecules phosphorylate glycogen synthase A and they transform the glycogen synthase A which are the molecules in their active form into glycogen synthase B which exists predominantly in their inactive form.