Evaluation of the role of parasite's Argonaute on infection by Leishmania braziliensis

• Grant number: 23/18057-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: May 01, 2024
• End date: October 31, 2026
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Angela Kaysel Cruz
• Grantee: Lissur Azevedo Orsine
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Leishmaniasis refers to a group of diseases with a high degree of diversity of manifestations, with the interaction between host and parasite being a determining factor. Although some of the molecular mechanisms behind this relationship are well described, there is still much to be studied, including species-specific aspects and their respective implications for pathology. Leishmania braziliensis is the main causative agent of cutaneous leishmaniasis in South America, and can also lead to the severe mucocutaneous form. Although the existence of a functional RNA interference (RNAi) pathway has already been demonstrated in L. braziliensis, the possible relationship of this gene expression regulation mechanism in host-parasite interaction during the infection process has not been evaluated yet. Thus, the general objective of this research project is to investigate the possible role of a central component of the RNAi pathway, the argonauteprotein, in L. braziliensis infection. For this, LbrAGO1 knockout cell line generated from CRISPR-Cas9 will be used in an in vitro infection assay of human macrophages and the RNA content of infected macrophages will be analyzed via dual RNA-Seq. As the RNAi pathway is articulated through non-coding RNAs (ncRNAs), these will be highlighted among the differentially expressed genes and the possible modulation of host mRNAs will be evaluated. Available data show that LbrAGO1 transcript is among the top expressed genes regardless of developmental stage, which allows us to speculate that the RNAi pathway may also play a role in infection. In a preliminary in silico analysis, we identified a set of 211 ncRNAs that may be carried by the argonaute and transferred via exosome for the host, indicating that, in fact, ncRNAs may be involved in the host-parasite interaction. This study aims to contribute to the understanding of the RNAi pathway in L. braziliensis, as well as to increase knowledge about the molecular mechanisms of infection in this species, potentially pointing out possible therapeutic targets.