INVESTIGATION OF THE INTERFERENCE OF GUAPIAÇU VIRUS, AN INSECT-SPECIFIC ORTHOFLAVIVIRUS, IN THE MULTIPLICATION AND TRANSMISSION CYCLE IN MEDICALLY IMPORTANT ARBOVIRUSES

• Grant number: 24/22180-5
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: June 01, 2025
• End date: July 31, 2027
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Maurício Lacerda Nogueira
• Grantee: Igor da Silva Teixeira
• Host Institution: Faculdade de Medicina de São José do Rio Preto (FAMERP). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São José do Rio Preto , SP, Brazil
• Associated research grant: 22/03645-1 - Study of the virus-vector interaction and the mechanisms involved in modulating the dynamics of viral transmission, AP.TEM

Abstract

Arboviruses are RNA viruses transmitted by hematophagous arthropods, such as mosquitoes of the Aedes genus, responsible for severe diseases like dengue and chikungunya, which are highly prevalent in tropical regions. These viruses maintain a complex cycle between vectors and vertebrate hosts, posing a serious public health issue in Brazil, exacerbated by vector resistance to conventional control strategies. In this context, insect-specific viruses (ISVs) emerge as promising tools for combating arboviruses. Unable to infect vertebrates, ISVs can reduce vector competence by interfering with arbovirus replication in mosquitoes. Among ISVs, the Guapiaçu virus (GUAPV), an Orthoflavivirus identified in mosquitoes from the São José do Rio Preto region, stands out. Preliminary results demonstrated the isolation of GUAPV, which does not induce cytopathic effects in Aedes cells, with viral loads consistent with persistent infections. Additionally, CHIKV and DENV viruses were isolated from mosquitoes and human samples, enabling comparative analyses of viral adaptation and vector competence. Thus, it is suggested that GUAPV may interfere with the replicative cycle of arboviruses like DENV and CHIKV, modulating their transmission. The interaction of GUAPV with the RNA interference (RNAi) pathway also represents a potential mechanism for arbovirus control. Therefore, this project aims to investigate the interference of GUAPV in the replication and transmission cycles of DENV1-2 and CHIKV through in vitro and in vivo assays, as well as to explore the role of the RNAi pathway, contributing to the development of innovative strategies for vector control and arbovirus mitigation.