title: A P-Glycoprotein Is Linked to Resistance to the Bacillus thuringiensis Cry3Aa Toxin in a Leaf Beetle.
abstract: Chrysomela tremulais a polyvoltine oligophagous leaf beetle responsible for massive attacks on poplar trees. This beetle is an important model for understanding mechanisms of resistance toBacillus thuringiensis(Bt) insecticidal toxins, because a resistantC. tremulastrain has been found that can survive and reproduce on transgenic poplar trees expressing high levels of the Cry3Aa Bt toxin. Resistance to Cry3Aa in this strain is recessive and is controlled by a single autosomal locus. We used a larval midgut transcriptome forC. tremulato search for candidate resistance genes. We discovered a mutation in an ABC protein, member of the B subfamily homologous to P-glycoprotein, which is genetically linked to Cry3Aa resistance inC. tremula. Cultured insect cells heterologously expressing this ABC protein swell and lyse when incubated with Cry3Aa toxin. In light of previous findings in Lepidoptera implicating A subfamily ABC proteins as receptors for Cry2A toxins and C subfamily proteins as receptors for Cry1A and Cry1C toxins, this result suggests that ABC proteins may be targets of insecticidal three-domain Bt toxins in Coleoptera as well.
authors.affiliation: Department of Entomology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, Jena 07745, Germany. ypauchet@ice.mpg.de.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Pauchet
authors.affiliation: Department of Entomology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, Jena 07745, Germany. abretschneider@ice.mpg.de.
authors.forename: Anne
authors.initials: A
authors.lastname: Bretschneider
authors.affiliation: Unité de Zoologie Forestière, Institut National de la Recherche Agronomique (INRA), 2163 Avenue de la Pomme de Pin, CS 40001 Ardon, Orléans 45075 CEDEX 2, France. sylvie.augustin@inra.fr.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Augustin
authors.affiliation: Department of Entomology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, Jena 07745, Germany. heckle@ice.mpg.de.
authors.forename: David G
authors.initials: DG
authors.lastname: Heckel
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics*; D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000633:toxicity*; D002460:Cell Line; D001517:Coleoptera / Q000187:drug effects* / Q000235:genetics; D004731:Endotoxins / Q000633:toxicity*; D005260:Female; D006460:Hemolysin Proteins / Q000633:toxicity*; D007305:Insecticide Resistance / Q000235:genetics; D008297:Male
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis
keywords: ABC proteins; Bt Cry3Aa toxin; Bt resistance; Chrysomela tremula; leaf beetle