title: Spider venom toxin protects plants from insect attack.
abstract: Many of the toxin proteins, that have been heterogeneously expressed in agricultural crops to provide resistance to insect pests, are too specific or are only mildly effective against the major insect pests. Spider venoms are a complex cocktail of toxins that have evolved specifically to kill insects. Here we show that the omega-ACTX-Hv1a toxin (Hvt), a component of the venom of the Australian funnel web spider (Hadronyche versuta) that is a calcium channel antagonist, retains its biological activity when expressed in a heterologous system. Expressed as a fusion protein in E. coli, the purified toxin fusion immobilized and killed Helicoverpa armigera and Spodoptera littoralis caterpillars when applied topically. Transgenic expression of Hvt in tobacco effectively protected the plants from H. armigera and S. littoralis larvae, with 100% mortality within 48 h. We conclude that the Hvt is an attractive and effective molecule for the transgenic protection of plants from herbivorous insects which should be evaluated further for possible application in agriculture.
authors.affiliation: Plant Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P.O. Box 577, Faisalabad, Pakistan.
authors.forename: Sher Afzal
authors.initials: SA
authors.lastname: Khan
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Zafar
authors.forename: Rob W
authors.initials: RW
authors.lastname: Briddon
authors.forename: Kauser Abdulla
authors.initials: KA
authors.lastname: Malik
authors.forename: Zahid
authors.initials: Z
authors.lastname: Mukhtar
mesh_terms: D060848:Agatoxins; D000818:Animals; D015139:Blotting, Southern; D002851:Chromatography, High Pressure Liquid; D004926:Escherichia coli / Q000378:metabolism; D008957:Models, Genetic; D010572:Pest Control, Biological / Q000379:methods*; D010935:Plant Diseases / Q000235:genetics; D010944:Plants / Q000378:metabolism; D030821:Plants, Genetically Modified; D013111:Spider Venoms / Q000378:metabolism*; D013112:Spiders; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism; D014118:Toxins, Biological / Q000494:pharmacology*; D019076:Transgenes
chemical_list: D060848:Agatoxins; D013111:Spider Venoms; D014118:Toxins, Biological; C060465:omega-agatoxin I