The objectives of the proposed research are to investigate the membrane properties and molecular recognition mechanisms in vertebrate olfactory receptor neurons by combining neurophysiological and biochemical techniques. Electrophysiological techniques will be used to monitor receptor cell activity evoked by orthodromic chemical stimulation by critically selected odors and antidromic electrical stimulation of the receptor cell axon. Carefully selected protein modifying reagents will be employed to probe the characteristics of membrane proteins associated with odor recognition mechanisms and impulse initiation and transmission.