The role of host cell Na+/H+ exchanger in invasion by Trypanosoma cruzi metacyclic forms

• Grant number: 19/10858-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: October 01, 2019
• End date: September 30, 2022
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Nobuko Yoshida
• Grantee: João Paulo Ferreira Rodrigues
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 16/15000-4 - Trypanosoma cruzi: intra and interspecific genomic variability and mechanisms of cell invasion/egress, AP.TEM

Abstract

NHE-1 (Na+/H+ exchanger isoform 1), a member of a large family of integral membrane proteins, is found virtually in all tissues and cells of mammals and is necessary for many physiological processes. By regulating intracellular pH, NHE-1 contributes for the actin filament reorganization. The activity of NHE-1 is regulated by extracellular signals mediated by diverse classes of cell surface receptors. In diverse cell types NHE-1 is localized at the plasma membrane basolateral domain, the preferential site of Trypanosoma cruzi entry. As the host cell invasion by T. cruzi metacyclic forms is influenced by intracellular pH and is associated with the actin cytoskeleton rearrangement and lysosome spreading, we aim to investigate whether NHE-1 is involved in the internalization of these forms, which is mediated by gp82. The surface molecule gp82, specific of metacyclic forms, binds to the host cells in a receptor-dependent manner and induces the actin cytoskeleton disorganization and the mobilization of lysosomes. We intend to examine the following questions: i) does the inhibition or depletion of NHE-1 in HeLa cells affect the invasion by metacyclic forms?; ii) does the inhibition or depletion of NHE-1 alter the actin cytoskeleton architecture and the distribution of lysosomes?; iii) is the binding of gp82 to cells affected by inhibition or depletion of NHE-1?; iv) what is the phosphorylation profile of PKC (protein kinase C) and ERK1/2 (extracellular signal-regulated protein kinase), components of signaling cascades implicated in actin-dependent invasion of diverse pathogenic microorganisms, in cells with inhibited or depleted NHE-1? (AU)