Evaluation of inflammasome activation by the Natterin-like protein encoded by the loc795232 gene in zebrafish

• Grant number: 24/16448-5
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2025
• End date: April 30, 2028
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Carla Lima da Silva
• Grantee: Felipe Justiniano Pinto
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 13/07467-1 - CeTICS - Center of Toxins, Immune-Response and Cell Signaling, AP.CEPID

Abstract

Thalassophryne nattereri, known as niquim, is a venomous fish from Brazil that has caused serious medical accidents. Studies by our group have identified a new family of proteins in the venom of this fish, the Natterins, with kininogenic activity and capable of reproducing symptoms of human poisoning in mice. In 2021, the Natterina family grew, incorporating 331 species that encode 859 natterin or natterin-like genes. Among them is the zebrafish, which has 10 genes that encode 11 natterin-like proteins, such as the protein NP_001013322.1 encoded by aep1 and XP_017212453.1 encoded by the gene LOC795232, which play a crucial role in embryonic development. Zebrafish have emerged as a powerful model due to their genetic homology with humans, contributing to studies of loss and gain of function, aiding in the discovery of previously uncharacterized protein functions. Furthermore, they are a valuable model for investigating inflammation and host defense mechanisms. Studies in zebrafish have elucidated the activation of the NLRP3 inflammasome, demonstrating similarities with mechanisms in mammals, despite evolutionary differences. Zebrafish express proteins essential for inflammasome formation, such as asc, nlrp3, caspase-a and gsdm. Their use in bacterial infections reveals inflammatory mechanisms and immune responses that are genetically inaccessible in other models, standing out as an effective tool for understanding important roles of macrophages and neutrophils in host defense against several bacteria, including Salmonella enterica serovar Typhimurium (ST). In this project we will silence the natterin-like gene using CRISPR/Cas9 to evaluate the action of the molecule in the immune defense of the organism against the gram-negative Salmonella typhimurium and the activation of the inflammasome complex. We believe it is possible to confirm the importance of Natterin family proteins as immune defense effector molecules in zebrafish through their ability to interact with members of the inflammasome complex.