Molecular characterization of transcription promoter sequences in Plasmodium

• Grant number: 23/18376-9
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: April 01, 2024
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Roberto Rudge de Moraes Barros
• Grantee: Thafne Plastina Astro
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated scholarship(s): 25/00663-7 - Use of RNA-seq technology to analyze transcriptional changes in Plasmodium knowlesi, BE.EP.DD

Abstract

Few transcriptional control elements have been identified in Plasmodium, and many are distinct from their eukaryotic counterparts. Members of the ApiAp2 Transcription Factor (TF) family were discovered and related to the development of sporozoites, ookinetes and gametocytes in P. berghei and P. falciparum. However, attempts to characterize P. vivax regulatory sequences using heterologous transfection of P. falciparum have failed, suggesting differences in the transcription control machinery between species.It was recently observed that the regulatory sequences of P. vivax - promoter sequences of the genes pvcrt (P. vivax chloroquine resistance transporter), pvcam (P. vivax calmodulin) and pvhsp70 (P. vivax heat shock protein 70) are capable of controlling the expression of a luciferase reporter gene in transgenic lines of P. knowlesi. The results indicate conservation of the transcription machinery and that these sequences may have highly conserved domains.To understand the transcriptional control of parasites from the primate malaria branch, we characterized the promoter sequence of the pvhsp70 gene to identify conserved domains. To achieve this objective, in silico analyzes and heterologous transfection experiments of P. knowlesi were carried out. To characterize the transcription of the hsp70 and crt genes of P. knowlesi and P. vivax we are carrying out real-time PCR and single-cell RNA sequencing experiments. These experiments allow us to observe the transcriptional control of these genes during the intraerythrocytic life cycle and in response to chloroquine (CQ) treatment. The results will allow us to better understand how transcriptional control works in P. knowlesi and P. vivax, and whether transcriptional changes may be involved in mechanisms of virulence and resistance to antimalarials.