Fig. 2.

The inferred subunit composition of some nematode neuromuscular junction nAChR. Different forms of the receptor are found elsewhere in the nervous system, and are activated by monepental and related drugs. (A) A levamisole-sensitive, but nicotine-insensitive nAChR was reconstituted in the Xenopus oocyte by co-expression of the C. elegans LEV-1, LEV_8, UNC-29, UNC-38 and UNC-63 subunits (Boulin et al., 2008). (B) A levamisole-sensitive nAChR reconstituted by co-expression of the indicated subunits from H. contortus (Boulin et al., 2011). (C) A levamisole- and oxantel-sensitive, but pyrantel-insensitive, nAChR reconstituted by co-expression of the indicated subunits from A. suum (Williamson et al., 2009). (D) A nicotine-sensitive, but levamisole-insensitive receptor is formed by expression of the C. elegans ACR-16 subunit (Raymond et al., 2000). (E) Omission of Hco-ACR-8 from the receptor shown in panel B results in a nAChR with reduced sensitivity to levamisole, but increased sensitivity to pyrantel (Boulin et al., 2011). (F). Changing the ratio of the Asu-UNC-29 and -UNC-38 subunits results in a receptor with increased sensitivity to nicotine and pyrantel, reduced sensitivity to levamisole and which is oxantel insensitive (Williamson et al., 2009).