The structure and evolution of adrenergic and muscarinic cholinergic receptors.

We have studied the molecular structures of the neurotransmitter receptors of the autonomic nervous system (alpha- and beta-adrenergic and muscarinic cholinergic receptors) using biochemical and immunological techniques. Each of these receptors has been purified and their molecular characteristics including molecular mass, isoelectric point, membrane topology, and quaternary structure have been determined. Limited proteolysis has identified structural and functional domains while complete digestion and peptide mapping by high performance liquid chromatography (HPLC) have allowed comparison of the various receptors. Purification and characterization of these neurotransmitter receptors have revealed considerable structural and functional homology between these pharmacologically distinct classes of information transduction molecules.