Tryptophan-containing weak neurotoxin

UniProtKB accession:  P82935

Grouped By:  Matching UniProtKB accession

UniProtKB description:  Neurotoxin that irreversibly inhibits nicotinic acetylcholine receptors (nAChR) and allosterically interacts with muscarinic acetylcholine receptors (mAChR) (PubMed:11279130, PubMed:19682302). The loop II is involved in the interaction of this toxin with nAChR and mAChR (PubMed:27343701, PubMed:26242733). On nAChR, it acts as a competitive antagonist (muscle-type and alpha-7/CHRNA7) with IC(50) values in the micromolar range (PubMed:11279130, PubMed:27343701). On mAChR, in presence of ACh, it partially inhibits the effect of acetylcholine (ACh) (allosteric antagonist), whereas in the absence of ACh, it activates the receptor (allosteric agonist) (PubMed:19682302). It also shows a very weak inhibition of GABA(A) receptor composed of alpha-1-beta-3-gamma-2 (GABRA1 and GABRB3 and GABRG2) subunits (10 uM inhibit 31% current) (PubMed:26221036). In vivo, is nonlethal to mice at concentrations up to 20 mg/kg, but exerts a myorelaxant effect, induces a dose-dependent decrease in blood pressure and an increase in heart rate in mice and rats (PubMed:15581687, PubMed:17371532).