Regulation of Glucose metabolism in Liver Cells in response to Blood Sugar Levels
High Blood Glucose	Low Blood Glucose
Enzymes involved in regulation of glucose metabolism: GS= Glycogen Synthase GP= Glycogen Phosphrylase PFK-1 = PhosphoFructoKinase PFK-2 = PhosphoFructoKinase (fructose 2,6, bisphophate forming) _____ This protein also contains the fructose-2,6-bisphosphatase activity FBPase = Fructose 1,6 BisPhosphatase PDH = Pyruvate DeHydrogenase Liver cells respond to organismal requirements as well as the internal metabolic state. Many cell types respond to insulin (released by the pancreas in response to increaing blood glucose levels), which induces glucose uptake from the blood. Liver cells are also induced to increase glycogen synthesis and glycolysis by insulin. Liver cells also respond to glucagon (released by the pancreas in response to low blood glucose levels) by increaing both glycogen breakdown and gluconeogenesis so that glucose can be shipped out to the circulation system. The regulation of the enzymes is accomplished by a series of lcovalent modification events that leads to the phosphorylation of GS (to inactivate) GP (to activate) and PFK-2 (activates the F26BPase activity and ihibts the PFK-2 activity) Kepp in mind that the allosteric regulation events are ALSO still effect for all of the enzmes shown!!!!