PESTICIDAL FUSIONS

摘要

Disclosed are polynucleotides encoding a pesticidal fusion polypeptide comprising (i) a toxin domain; and (ii) a heterologous binding domain capabl e of binding non-specifically to a cell membrane without disrupting that membrane. Preferably the toxin domain is derived from a Bacillus thuringiens is cry toxin (e.g. CryIA (b) or (c)) and the binding domain is derived from a lectin (e.g. ricin toxin B chain). The use of such fusions may help to inhib it the acquisition of resistance in a pest population treated with the polypeptide. A further aspect of the invention is a method of assessing the toxicity of a polypeptide to a pest species by expressing a nucleic acid encoding said polypeptide in a host cell from that species, observing the viability of the cell and correlating the results of the observation with th e toxicity of the polypeptide, wherein the viability is determined by assessin g esterase activity or membrane integrity.