Résumé
The nicotinic acetylcholine receptor (AChR) is a membrane-bound allosteric protein which operates, in the millisecond timescale, as an acetylcholine-gated cationic channel. The functional architecture of this heterologous α2 β γ δ pentamer is actively investigated (Changeux, 1981; Popot and Changeux, 1984; Hucho, 1986; Changeux et al., 1987; Lindstrom et al., 1987 and several papers in this Volume) and the regions of the molecule which form its two main functional domains: the acetylcholine binding site (Kao et al., 1984; Dennis et al., 1988) and the agonist gated ion channel (Giraudat et al., 1986, 1988; Oberthür et al., 1986; Hucho et al., 1986; Imoto et al., 1986, 1988; Leonard et al. in press; Oiki et al. in press) have recently been defined at the amino acid level.