N.vectensis toxin 14 of 85 aas and 1 N-terminal TMS. It binds to site 3 of voltage-gated sodium channels and inhibits the inactivation process (Moran et al. 2008). It is highly active on DmNav1/TipE (Drosophila) and is only weakly active on rat Nav1.4-beta-1/SCN4A-SCN1B, or on human Nav1.5-beta-1/SCN5A-beta-1. This reveals high specificity for arthropod over mammalian channels (Moran et al. 2008). In vivo, when released into the medium, this recombinant toxin induces impaired swimming, paralysis and death of the crustacean A.nauplii within several hours (Moran et al. 2012) and causes paralysis of cherry shrimps immediately after injection at very low doses (Columbus-Shenkar et al. 2018). Its effect on zebrafish (D.rerio) larvae is also rapid, since it induces tail twitching accompanied by impaired swimming after 20 minutes and complete paralysis within 45 minutes (Moran et al. 2012). It has also been observed to cause death of zebrafish larvae within 1 hour (Sachkova et al. 2019).