SINGLE BINDING VERSUS SINGLE-CHANNEL RECORDINGS - A NEW APPROACH TO STUDY IONOTROPIC RECEPTORS

The observation of ligand binding to a single molecule has become feas ible with recent developments in laser-based fluorescence microscopy, We have simulated such single ligand-binding events for the nicotinic acetylcholine receptor in order to provide comparisons with single cha nnel events under pulsed agonist conditions. The binding events would be more complex than ionic events due to multiple interconversions bet ween different conformational states at the same degree of ligation, N evertheless, recording of such events could provide valuable new infor mation concerning the role of ligand binding in stabilizing conformati onal changes and the degree of functional nonequivalence of the bindin g sites.