This toxin activates voltage-gated sodium channels (Nav1.3/SCN3A (EC(50)=3.98 nM), Nav1.4/SCN4A (EC(50)=4.99 nM), Nav1.6/SCN8A (EC(50)=1.27 nM) and Nav1.7/SCN9A (EC(50)=2.42 nM)). It shifts the voltage-dependence of activation to more hyperpolarized potentials but has only little effect on channel inactivation. In vivo, it induces nocifensive or pain-like behaviors in mice when injected intraplantarly. This is coherent with the specific defensive role deduced from its proximal position in the venom gland. Expressed by the venom duct, in the proximal part (indicative of a defensive role). The cysteine framework is VI/VII (C-C-CC-C-C). The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. Monoisotopic mass. Belongs to the conotoxin O1 superfamily.