Membrane Receptors

Most receptors for biologically active molecules are found upon the cell surface. They recognize their appropriate ligands and bind them. This binding leads to a change in receptor conformation and thence to intracellular signals and responses. In some cases (hormone receptors), the sequence is of chemical activation through to a chemically mediated biological response, which may involve alterations in the electrical potential of the target cell. In the case of neurotransmitters the situation is slightly more complicated: A wave of depolarization passes down a nerve process (axon), causes the release of the appropriate chemical messenger that binds to a receptor, and may produce either an immediate (electrical) or a longer-term (chemical through to morphological) response. Cell surface receptors are many and varied. I shall describe only a few. In the case of those receptors that I describe, I shall comment upon their intracellular linkages and give my views about the relationship between their intracellular messengers and those that are induced by chemical messengers that act upon the genome. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.