PSL201Y1 Chapter Notes - Chapter 5: Guanosine, Geranylgeranyl Pyrophosphate, Gamma-Glutamyl Transpeptidase
Document Summary
Signal transduction mechanisms for responses mediated by intracellular. Receptors for lipophilic messengers are usually located in the cytosol or nucleus of the target cells and are readily accessible cause these messengers easily permeate the plasma membrane. Steroid hormones bind to receptors in the cytosol, although some can bind to nuclear receptors and others bind to receptors in the plasma membrane. For the steroid hormone complex to activate or deactivate a particular gene, 2 complexes must bind to the hre in a process called dimerization. As a result a medium is needed in order for ions to pass through. They are proteins and are speci c; allowing only one type of ion or class of ions to pass through them. They are located across the lipid bilayer and they can be regulated; open and closed. Ion channels that open or close in response to the binding of a chemical to a receptor are called ligand-gated channels.
