Is stimulation of class-I phosphatidylinositol 3-kinase activity by insulin sufficient to activate pathways involved in glucose metabolism

In summary, it is still unclear which type of PI 3-kinase is involved in the activation of glycogen synthase. However, there is a strong body of evidence to suggest class-1 PI 3-kinase activity is necessary for insulin stimulation of glucose transport and a growing body of evidence to suggest that insulin stimulation of this class of PI 3-kinase is sufficient to stimulate glucose transport. However, the mechanism by which PI 3-kinase lipid products stimulate glucose transport is still not clear.