Question

Please describe the reciprocal regulation of glycogenolysis and glycogenesis and highlight the major hormonal differences.

Answer 1

Gluconeogenesis is the production of glucose from non-carbohydrate sources, whereas glycogenolysis is the process of glycogen breakdown. During glycogenolysis, glycogen is broken down to form the glucose-6-phosphate, and during gluconeogenesis, molecules such as amino acids and lactic acids convert into glucose.

Please see the image for the regulation.

RECIPROCAL REGULATION OF GLYCOLYSIS AND GLUCONEOGENESIS GLYCOLYSIS GLUCONEOGENESIS Enzyme Regulation Enzyme Regulation Hexokinase product inhibited not product inhibited in liver and pancreatic ß cells glucokinase regulatory protein (liver) glucgon signaling insulin signaling 1 Glucose 6-phosphatase only in liver and kidney glucgon signaling 1 insulin signaling Glucokinase Phosphofructokinase 1 F 2.6-bisP AMP 1 ATP! citrate, low pH 1 Fructose 1,6-bisPhosphatase F 2,6-bisP AMP, citrate 1 F 6-P glucgon signaling 1 insulin signaling Pyruvate Carboxylase Pyruvate Kinase F 1,6-bisP ATP alanine, glucgon signaling insulin signaling 1 acetyl COAT ADP ADP glucagon signaling | insulin signaling Phosphoenolpyruvate carboxykinase Pyruvate dehydrogenase pyruvateľ insulin signalingi acetyl CoA. ATP) NADH There are no opposing enzymatic steps. Acetyl CoA cannot be used to generate pyruvate.

THe major hormonal difference is the production and degradation of glucose using glucagon hormone. Glucagon is a hormone produced by the alpha cells of the pancreas and stimulates glycogenolysis and gluconeogenesis, causing an increase in blood glucose. It has the opposite effect as that of insulin.