8.B.28.1.2
Conotoxin (conopeptide) PIIIA of 73 aas. Mu-conotoxins block voltage-gated sodium channels (Nav). This toxin potently but reversibly blocks rNav1.4/SCN4A and moderately blocks rNav1.1/SCN1A, rNav1.2/SCN2A, rNav1.3/SCN3A, mNav1.6/SCN8A, and h/rNav1.7/SCN9A. The block of SCN1A, SCN2A, and SCN8A is modified when beta-subunits are coexpressed with alpha subunits. Hence, blocks of channels containing beta-1 and beta-3 subunits are more potent (compared to channels without beta subunits), whereas blocks of channels containing beta-2 and beta-4 are less potent (also compared to channels without beta subunits). This peptide causes flaccid paralysis in both mice and fish (Holford et al. 2009; Favreau et al. 2012; Zhang et al. 2013; Leipold et al. 2016).