Omega-conotoxins act at presynaptic membranes, they bind and block voltage-gated calcium channels (Cav). This toxin selectively and potently inhibits depolarization-activated rat Cav2.2/CACNA1B currents (IC(50)=89 nM), when coexpressed with alpha-2/delta-1 (CACNA2D1) and beta-3 (CACNB3) subunits. In vivo, is lethal to fish and displays potent analgesic activity in mice pain models of hot plate and acetic acid writhing but has fewer side effects on mouse motor function and lower toxicity in goldfish. Shows higher or similar analgesic activity in the pain models mentioned above compared to MVIIA, and lower side effects. In addition, it blocks Cav2.2/CACNA1B more rapidly than MVIIA and also dissociates more rapidly. Expressed by the venom duct. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. The cysteine framework is VI/VII (C-C-CC-C-C). LD(50) is 0.31 (0.22-0.41) mg/kg by intramuscular injection into goldfish (after 4 hours). Shows very weak activity on Cav2.1/CACNA1A (27.36% current inhibition at 10 uM) and Cav1.1/CACNA1S (2.82% current inhibition at 10 uM), and no activity on sodium (Nav) and potassium (Kv) channels in rat DRG neurons. Belongs to the conotoxin O1 superfamily.