GCK and diabetes mellitus: Many key enzymes involved in hepatic glucose metabolism, such as glycogen phosphorylase (GP, Pygl) the rate-limiting enzymes of glycogenolysis [6], fructose-1,6-bisphosphatase (FBPase, Fbp1) and glucose 6-phosphatase (G6pase, G6pc) the major control points in the pathway of gluconeogenesis [7], [8], and glucokinase (GK/HK, Gck) the key enzyme of glycolysis [9], are the potential targets for diabetes.