Bacillus thuringiensis Cry1Ac action mechanism on Helicoverpa armigera (Lepidoptera: Noctuidae)

• Grant number: 18/13974-7
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): November 01, 2018
• Effective date (End): September 01, 2020
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal researcher: Ricardo Antonio Polanczyk
• Grantee: Igor Henrique Sena da Silva
• Home Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated scholarship(s): 19/00264-4 - Mechanism of action of Cry1Ac toxin from Bacillus thuringiensis in Helicoverpa armigera (Lepidoptera: Noctuidae), BE.EP.DR

Abstract

Helicoverpa armigera (Hübner, 1805) (Lepidoptera: Noctuidae) is an important exotic pest, highly polyphagous and widely distributed. The use of Cry proteins, produced by the bacterium Bacillus thuringiensis (Bt) has been widely used to control this pest worldwide, either in the form of bioinsecticides and/or transgenic plants expressing proteins of this bacterium. Among the Cry toxins that have activity against H. armigera, Cry1Ac stands out as one of the most toxic. However, several aspects related to the mechanism of action of this toxin have not been elucidated. Recently, Cry1Ac toxin binding proteins in the early instars of H. armigera (larval stage highly sensitive to Cry1Ac toxin) were identified by imonuprecipitation analyzes followed by liquid chromatography coupled to mass spectrometry (BE-MS) FAPESP 2016/21464-3). Thus, 65 kDa Alkaline Phosphatase (ALP), four aminopeptidase-N (1, 2, 3 and 4) (APN), prohibitin and a selective anion channel protein were identified. The objectives of this project are to better analyze the functional role of these proteins in the toxicity of Cry1Ac on H. armigera, through different biotechnological and molecular techniques, as well as to validate the immunoprecipitation technique followed by LC-MS for correct identification of functional receptors for Cry toxins. With the results of the present project we hope to advance the knowledge in several aspects of the mechanism of action of the Cry1Ac toxin in H. armigera. In this way, to produce bio-insecticides, and/or transgenic cultivars more powerful against this insect and that, above all, they are able to delay the pest resistant evolution in the field. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SENA DA SILVA, IGOR HENRIQUE; GOMEZ, ISABEL; PACHECO, SABINO; SANCHEZ, JORGE; ZHANG, JIE; LUQUE CASTELLANE, TEREZA CRISTINA; DESIDERIO, JANETE APARECIDA; SOBERON, MARIO; BRAVO, ALEJANDRA; POLANCZYK, RICARDO ANTONIO. Bacillus thuringiensis Cry1Ab Domain III beta-16 Is Involved in Binding to Prohibitin, Which Correlates with Toxicity against Helicoverpa armigera (Lepidoptera: Noctuidae). Applied and Environmental Microbiology, v. 87, n. 2 JAN 2021. Web of Science Citations: 1.