RESUMEN
A full-length cDNA sequence encoding for the precursor of a venom peptide (named BmKCT) with homology to chlorotoxin has been isolated from a cDNA library made from the venom glands of the Chinese Scorpion Buthus martensii Karsch. The sequence of BmKCT is similar (68 % identities) to that of chlorotoxin isolated from Leiurus quinquestriatus quinquestriatus. To understand the biological function of BmKCT, this peptide was expressed using pGEX expression system and purified using GST affinity column and gel filtration.Whole cell patch-clamping recording showed that BmKCT could significantly inhibit chloride currents of gliomas cells, and the inhibitory effect was reversible. These results suggested that BmKCT might belong to the class of short chain toxins blocking the chloride ion channels.