Toxin with unknown function in healthy organisms. On glioma cells, interacts with chloride channels (probably ClC-3/CLCN3) and MMP2 at the surface of glioma cells. This complex is then internalized via caveolae, thus inhibiting the chloride channels necessary for cell shrinkage and tumor propagation (By similarity). Induces flaccid paralysis in H.virescens larvae. Is not toxic to S.falculata larvae or mice. Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. Could be considered as a biological insecticide candidate, when fused to Galanthus nivalis agglutinin (GNA), a protein with the potential to cross the insect gut. This chimeric ButaIT/GNA variant shows a gain in toxicity against insects when administered orally, while maintaining similar effects as the wild-type toxin when injected (toxic to insects and non-toxic to mammals). Belongs to the short scorpion toxin superfamily. Chloride channel inhibitor family.