BIO310H5 Lecture Notes - Lecture 8: Glycogen Phosphorylase, Cytosol, Blood Sugar
Document Summary
Mode of action: second messengers: cyclic nucleotides camp, cgmp inositol phospholipid hydrolysis inositol 1,4,5 triphosphate (ip3) Cyclic nucleotide monophosphates; camp and cgmp amplification of signal transducer g-protein remains active as far as gtp is bound camp binds to the inhibitory regulatory subunit and dissociates it. One hormone molecule stimulates one receptor (1:1 relationship) How can one second messenger mediate incompatible biochemical and physiological responses? tissue distribution of the effector proteins that can be phosphorylated by protein kinase. A is different it depends on the cell. Amplification through enzyme cascades glucagon: increases the breakdown of glycogen in the liver. Epinephrine: same effect in skeletal and cardiac muscles. Both also stimulate gluconeogenesis and inhibit glycogenesis. One molecule of either of these hormones can yield thousands of molecules of glucose (the the goal: increase blood glucose levels amplification that occurs through enzyme activity) A single hormone may bind to different receptors, initiating convergent and/or divergent signalling.
