Mechanism of action of Cry1Ac toxin from Bacillus thuringiensis in Helicoverpa armigera (Lepidoptera: Noctuidae)

• Grant number: 19/00264-4
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): May 04, 2019
• Effective date (End): January 03, 2020
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal researcher: Ricardo Antonio Polanczyk
• Grantee: Igor Henrique Sena da Silva
• Supervisor abroad: Alejandra Bravo
• Home Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Research place: Universidad Nacional Autónoma de México, Morelos (UNAM), Mexico
• Associated to the scholarship: 18/13974-7 - Bacillus thuringiensis Cry1Ac action mechanism on Helicoverpa armigera (Lepidoptera: Noctuidae), BP.DR

Abstract

Helicoverpa armigera (Hübner, 1805) (Lepidoptera: Noctuidae) is an important exotic pest, highly polyphagous and widely distributed. The use of Cry toxins from Bacillus thuringiensis (Bt) has been broadly used to control this pest worldwide, as bioinsecticides or transgenic plants expressing toxins of this bacterium (Bt plants). Among the Cry toxins that possess 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 remain unclear. Recently, were identified by pull-down followed by liquid chromatography coupled to mass spectrometry (LS-MS) the Cry1Ac-binding proteins in the early instars of H. armigera (larval stage highly sensitive to Cry1Ac toxin) (FAPESP 2016/21464-3). Thus, were identified alkaline phosphatase (ALP), aminopeptidase-N (APN) and prohibitin (PHB). The aim of this project are: analyze the functional role of these proteins in the mechanism of action of Cry1Ac in H. armigera, as well as other proteins previously identified as receptors for Cry toxins in other lepidopteran pest, such as cadherin (CAD) and a member of the ABC transporter (ABCC2). Furthermore, validate the pull-down technique followed by LC-MS for correct identification of functional receptors for Cry toxins. With the results of this project, we hope to provide several insights in knowledge of the mechanism of action of the Cry1Ac toxin in H. armigera. Thus, be able to produce bioinseticides and transgenic plants more potent against this insect pest and mainly be able to retard the insect resistance evolution in the field.

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.