Banca de QUALIFICAÇÃO: KAMILA LEITE DE AMORIM MAGALHÃES

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : KAMILA LEITE DE AMORIM MAGALHÃES
DATE: 30/10/2025
TIME: 14:00
LOCAL: https://meet.google.com/icn-uhsd-ijy
TITLE:

Study of the immune response of Aedes aegypti (Diptera: Culicidae) after challenge with entomopathogenic fungus

KEY WORDS:

Biological control, Metarhizium, Mosquito vectors, Gene expression, Antimicrobial peptides, Innate immunity

PAGES: 53
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SUMMARY:

The mosquito Aedes aegypti is one of the main vectors of arboviruses such as dengue, Zika, and chikungunya, representing a major global public health challenge. The continuous use of chemical insecticides has led to the emergence of resistance, reinforcing the need for alternative strategies such as biological control using entomopathogenic fungi. In this context, understanding the immune response of the vector to fungal infection is essential to identify potential targets for intervention. This study evaluated the expression of genes related to the main innate immune pathways (Toll, IMD, and JAK-STAT) and antimicrobial peptides (defensin and cecropin) in A. aegypti larvae of the Rockefeller strain infected with Metarhizium anisopliae sensu lato (isolate CG 153). Second-instar (L2) larvae were exposed to conidial suspensions (1 × 10⁵ conidia mL⁻¹) under controlled temperature (27 ± 2 °C) and humidity (≥ 80%). After 24 and 48 hours of exposure, intestines, fat bodies, and whole larvae were collected for RNA extraction, cDNA synthesis, and gene expression analysis by RT-qPCR, using RPS17 as the reference gene. Statistical analysis was performed using ANOVA followed by Tukey’s test (p < 0.05). The results demonstrated that the immune response is both tissue and time-dependent. The Toll pathway showed strong induction of TOLL-5A in the fat body and repression in the intestine and whole larvae, while Rel1 and Cactus indicated selective modulation. The IMD pathway exhibited punctual activation, mainly through PGRP-LC in the intestine and Rel2 in whole larvae. The JAK-STAT pathway displayed robust activation of DOME and STAT, with strong PIAS induction at 48h. Among antimicrobial peptides, defensin was repressed in the fat body, whereas cecropin was strongly induced in this tissue. In conclusion, the immune response of A. aegypti to M. anisopliae infection is multifactorial and selective, with the fat body acting as the main site of late activation and cecropin as the primary antifungal effector.

COMMITTEE MEMBERS:
Presidente - 2860277 - ISABELE DA COSTA ANGELO
Externa ao Programa - 1299153 - PATRICIA GONZAGA PAULINO - UFRRJExterno à Instituição - EVERTON KORT KAMP - UFG
Externo à Instituição - NICOLÁS PEDRINI