BIOL 1080 Study Guide - Midterm Guide: Glycogenolysis, Cystic Fibrosis, Gluconeogenesis
Document Summary
Lipid-soluble (lipophilic or hydrophobic) chemical messengers diffuse through membranes and bind to cytosolic or nuclear receptors: turn on genes to make new proteins (enzymes, fast response but short duration. Cells express many different types of receptors and there can be 100s or 1000s of a given receptor on a cell surface. The amount of a receptor is controllable (can be up or down regulated) The response of a cell to a given messenger can be tissue specific based on the type of receptor. One messenger causes lots of change in the protein. Amplification during: step 3: one hormone/receptor complex can cause many mrna to be formed, step 4: many proteins are formed from each mrna. Signal transduction and amplification in water soluble messengers. Some water-soluble ligands can influence the nucleus (gene expression through their second messengers: myostatin acts as in inhibitor of muscle protein synthesis.
