Banca de QUALIFICAÇÃO: MANOELY ABREU REIS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MANOELY ABREU REIS
DATE: 28/02/2023
TIME: 09:00
LOCAL: Recife
TITLE:

IDENTIFICATION AND CHARACTERIZATION OF THE MAIN PATHWAY GENES OF THE IMMUNE SYSTEM OF Diatraea saccharalis IN RESPONSE TO Metarhizium anisopliae, Bacillus thuringiensis AND THE PARASITOID Tetrastichus howardi

KEY WORDS:

Toll, IMD, Jak-STAT, humoral response, biological control agent

PAGES: 40
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitossanidade
SPECIALTY: Entomologia Agrícola
SUMMARY:

The innate immune system of an insect is made up of cellular and humoral responses. The humoral response is important in the body's defense because it produces antimicrobial peptides as a result of the Toll, IMD, and JAK/STAT signaling pathways. Each of these pathways is well described for the model Drosophila melanogaster, where Toll responds to Gram-positive bacteria, fungi, and parasitoids, the IMD pathway responds to Gram-negative bacteria, and JAK/STAT is involved in the defense against viral infection and parasitoid parasitism, among other things. However, most model organism studies are conducted with non-pathogenic or opportunistic organisms, or when using a natural pathogen, the infection conditions are not natural. To better understand the activation profile of the humoral response in natural conditions of infection or parasitism, we examined the expression of the main transcription factors of the aforementioned pathways in insects challenged with the fungus Metarhizium anisopliae, the bacterium Bacillus thuringiensis, and the parasitoid Tetrastichus howardi. Diatraea saccharalis, the main pest of sugarcane in Brazil, served as our study model. We chose DsDorsal (via Toll), DsRelish (via IMD), and DsSTAT (via JAK/STAT) as target genes for our study. According to our findings, M. anisopliae inhibited the expression of DsDorsal and DsSTAT in the early stages of infection (24h). B. thuringiensis, on the other hand, induced the expression of DsRelish (24 and 48 h of treatment) and DsSTAT (48 h). Finally, DsDorsal and DsSTAT were upregulated in T. howardi larvae but not in pupae. Therefore, we determined the expression profile of the main humoral response genes of D. saccharalis challenged with various biological control agents. Furthermore, we explain why T. howardi is more effective at parasitizing pupae than D. saccharalis larvae. The data generated here open up new avenues for improving pest management through the use of biological control agents.

COMMITTEE MEMBERS:
Presidente - JOSE DIJAIR ANTONINO DE SOUZA JUNIOR
Interna - ***.393.814-** - ROBERTA RAMOS COELHO - UFRPE
Externo à Instituição - RICARDO ANTONIO POLANCZYK - UNESP