Identification of Diatraea saccharalis Olfactory Receptor in the Insect-Fungi Interaction

• Grant number: 18/15795-2
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: November 13, 2018
• End date: November 12, 2019
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: José Maurício Simões Bento
• Grantee: Flávia Pereira Franco
• Supervisor: Walter Soares Leal
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Institution abroad: University of California, Davis (UC Davis), United States
• Associated to the scholarship: 16/25634-0 - Identification of Diatraea saccharalis olfactory receptor in the insect-fungi interaction, BP.PD

Abstract

Colonization of sugarcane stalk by opportunistic fungi, such as Fusarium verticillioides and Colletotrichum falcatum, usually occurs after Diatraea saccharalis (Lepidoptera: Crambidae) caterpillars attack. Our previous studies have shown an important synergistic interaction between D. saccharalis and these fungi on sugarcane. D. saccharalis seems to create a favorable environment to C. falcatum development in sugarcane. The fungus infection in sugarcane is highly increased when associated to the caterpillar. In addition, both fungi C. falcatum and F. verticillioides have shown to attract and positively influence D. saccharalis feeding due the release of volatile organic compounds (VOCs). Recently, we performed RNA next generation sequencing in D. saccharalis caterpillar head, to find sequences of odorant receptors (OR) responsive to fungal VOCs and we selected OR candidates genes. Therefore, the goal of this project is to deorphanize D. saccharalis OR responsive to fungal volatiles. For this approach, we will identify expression profiles of encoding genes to odorant receptors; perform cloning and expression of these genes in Xenopus laevis oocytes, for identification and characterization of active receptors responsive to fungal volatiles by Two-electrode voltage-clamp technique (TEVC). This new challenge will decipher another stage of the complex network of plant-insect-fungus interaction, and can reveal important targets for the development of biotechnological strategies to D. saccharalis control.