Silencing of an ABC transporter, but not a cadherin, decreases the susceptibility of Colorado potato beetle larvae to Bacillus thuringiensis ssp. tenebrionis Cry3Aa toxin. Issue 2 (19th July 2021)

• Record Type: Journal Article
• Authors: Güney, Gözde; Cedden, Doğa; Hänniger, Sabine; Heckel, David G.; Coutu, Cathy; Hegedus, Dwayne D.; Mutlu, Damla Amutkan; Suludere, Zekiye; Sezen, Kazım; Güney, Ebru; Toprak, Umut
• Is Part Of: Archives of insect biochemistry and physiology. Volume 108:Issue 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-07-19
• Subjects: ABC transporter -- Bacillus thuringiensis ssp. tenebrionis -- Cadherin -- Leptinotarsa decemlineata -- RNAi; Insects -- Physiology -- Periodicals; Insect biochemistry -- Periodicals; 595.701572
• DOI: 10.1002/arch.21834
• Languages: English
• ISSNs: 0739-4462

Abstract

Abstract: The Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae), is a major pest of potato plants worldwide and is notorious for its ability to develop resistance to insecticides. Cry3 toxins synthesized by Bacillus thuringiensis ssp. tenebrionis have been used successfully to manage this pest. Resistance to Cry toxins is a concerning problem for many insect pests; therefore, it is important to determine the mechanisms by which insects acquire resistance to these toxins. Cadherin‐like and ABC transporter proteins have been implicated in the mode of action of Cry toxins as mutations in these genes render lepidopterans resistant to them; however, clear consensus does not exist on whether these proteins also play a role in Cry3 toxin activity and/or development of resistance in coleopterans. In the current study, we identified the L. decemlineata orthologues of the cadherin (LdCAD) and the ABCB transporter (LdABCB1) that have been implicated in the mode of action of Cry toxins in other coleopterans. Suppression of LdABCB1 via RNA interference reduced toxin‐related larval mortality, whereas partial silencing of LdCAD did not. Our results suggest that the ABCB is involved in the mode of action of Cry3Aa toxins; however, no evidence was found to support the role of cadherin as a receptor of Cry3Aa in L. decemlineata . Research highlights: A cadherin (LdCAD) and ABC transporter 1 (LdABCB1) were identified from L. decemlineata . Suppression of the LdABCB1 reduced Cry3Aa‐related larval mortality. Silencing LdCAD disrupted midgut epithelium but did not change the Cry3Aa‐related larval mortality. Abstract : dsRNA mediated silencing of LdABCB1 leads to reduce Bacillus thuringiensis ssp. tenebrionis Cry3Aa toxin‐related mortality in Colorado potato beetle larvae, while silencing of LdCAD did not change the Cry3Aa‐related larval mortality.