<P> One of these pathways, involves the PI (3) K enzyme (Phosphoinositide 3 - kinase). This pathway is responsible for activating glycogen, lipid - protein synthesis, and specific gene expression of some proteins which will help in the intake of glucose . Different enzymes control this pathway . Some of these enzymes constrict the pathway causing a negative feedback like the GSK - 3 pathway . Other enzymes will push the pathway forward causing a positive feedback like the AKT and P70 enzymes . When insulin binds to its receptor, it activates the glycogen synthesis by inhibiting the enzymes that slow down the PI (3) K pathway such as PKA enzyme . At the same time, it will promote the function of the enzymes that provide a positive feedback for the pathway like the AKT and P70 enzymes . The inactivation of the enzymes that stop the reaction and activating of enzymes that provide a positive feedback will increase glycogen, lipid & protein syntheses and promote glucose intake . </P> <P> (Image to help explain the function of the proteins mentioned above in the positive feedback .) </P> <P> When insulin binds to the cell's receptor, it results in negative feedback by limiting or stopping some other actions in the cell . It inhibits the release and production of glucose from the cells which is an important part in reducing the glucose blood level . Insulin will also inhibit the breakdown of glycogen into glucose by inhibiting the expression of the enzymes that catalyzes the degradation of Glycogen . </P> <P> An example of negative feedback is slowing or stopping the intake of glucose after the pathway was activated . Negative feedback is shown in the insulin signal transduction pathway by constricting the phosphorylation of the insulin - stimulated tyrosine . The enzyme that deactivates or phosphorylates the insulin - stimulated tyrosine is called tyrosine phosphatases (PTPases). When activated, this enzyme provides a negative feedback by catalyzing the dephosphorylation of the insulin receptors . The dephosphorylation of the insulin receptor slows down glucose intake by inhibiting the activation (phosphorylation) of proteins responsible for further steps of the insulin transduction pathway . </P>

How does the signal cascade increase the response of the insulin receptor