PERIRECEPTOR EVENTS IN OLFACTION

Before reaching olfactory receptor neurons, odorant molecules have to cross an aqueous interface: the nasal mucus in vertebrates and the sen sillar lymph in insects, Biochemical interactions taking place between odorants and the elements of these phases are called perireceptor eve nts, Main protein constituents of these media, in both insects and ver tebrates, are OBPs (odorant-binding proteins), Another class of protei ns active in the olfactory perireceptor area includes odorant-degradin g enzymes, The structure and the properties of these major proteins, w ith particular reference to OBPs, are reviewed and their role in olfac tory transduction is discussed. (C) 1996 John Wiley & Sons, Inc.