Unravelling the biological role of T. cruzi protein glycosylation

• Grant number: 22/00796-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: March 01, 2022
• End date: November 10, 2024
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Giuseppe Palmisano
• Grantee: Lays Adrianne Mendonça Trajano Silva
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/15549-1 - Post-translational modifications in Chagas Disease biological processes and diagnostics: novel methodological approaches and biological applications, AP.JP2

Abstract

The survival of the parasite Trypanosoma cruzi during the cell cycle and establishment of the infection depends on specific processes that guarantee its adaptation in the most varied conditions. In this context, post-translational modifications, such as glycosylation, have been widely studied, mainly because they contain proteins that can be used as biomarkers for Chagas Disease. In T. brucei, oligosaccharyltransferase genes (STT3A and STT3B), present in the N-glycosylation machinery, were identified, and the silencing of the TbSTT3A and TbSTT3B genes demonstrated the consequent disappearance of most of the N-glycans paucimannose/complex or oligomannose, leading to a decrease in the growth of parasites in culture. However, in T. cruzi, the function of these genes remains uncharacterized. The wide use of the CRISPR/Cas9 tool has enabled advances in the functional study of proteins, especially in T. cruzi. In order to understand glycosylation in T. cruzi, the objective of this project is to identify the paralogs and characterize the function of oligosaccharyltransferase (OST) in T. cruzi using the CRISPR/Cas9 technique. The generation of knockout parasites will allow the evaluation of metacyclogenesis in epimastigote forms, in addition to infectivity in LLC-MK2 cells of trypomastigote forms after knockout. The results obtained will contribute to the understanding of the role of STT3 in the N-glycosylation process of T. cruzi and its relevance in the establishment of infection.