“…Despite Arg13 replacing the conserved Tyr13 critical for potent Ca v 2.2 inhibition in piscivorous ω-conotoxins 22 , 23 , the pharmacology of MoVIA and MoVIB closely resembles that of ω-conotoxins from fish-hunting cone snails, including those from C. consors , C. catus , C. fulmen , C. geographus , C. magus , C. radiatus , C. striatus and C. tulipa 22 , 23 , 38 , 43 , 44 . Indeed, MoVIA and/or MoVIB may be ancestral to GVIIA and/or GVIIB, given Tyr13 is also replaced by Arg13 and both have similar elongated and non-amidated C-termini, albeit those from C. geographus are ~100-fold lower affinity than the highly homologous GVIA at mammalian Ca v 2.2 16 , 45 . Similarly, the MVIIA-[Y13R] analogue also showed ~100-fold decrease in binding affinity over MVIIA and no functional activity at mammalian Ca v 2.2.…”