Calcium-sensitive pyruvate dehydrogenase phosphatase is required for energy metabolism, growth, differentiation, and infectivity of Trypanosoma cruzi

Autor(es)

Lander, Noelia ^[1] ; Chiurillo, Miguel A. ^[1] ; Bertolini, Mayara S. ^[1] ; Storey, Melissa ^{[2, 3]} ; Vercesi, Anibal E. ^[1] ; Docampo, Roberto ^{[2, 3, 1]}

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Dept Patol Clin, Fac Ciencias Med, BR-13083 Campinas, SP - Brazil

^[2] Univ Georgia, Ctr Trop & Emerging Global Dis, Athens, GA 30602 - USA

^[3] Univ Georgia, Dept Cellular Biol, Athens, GA 30602 - USA

• Tipo de documento: Artigo Científico
• Fonte: Journal of Biological Chemistry; v. 293, n. 45, p. 17402-17417, NOV 9 2018.
• Citações Web of Science: 4

Resumo

In vertebrate cells, mitochondrial Ca2+ uptake by the mitochondrial calcium uniporter (MCU) leads to Ca2+-mediated stimulation of an intramitochondrial pyruvate dehydrogenase phosphatase (PDP). This enzyme dephosphorylates serine residues in the E1 subunit of pyruvate dehydrogenase (PDH), thereby activating PDH and resulting in increased ATP production. Although a phosphorylation/dephosphorylation cycle for the E1 subunit of PDH from nonvertebrate organisms has been described, the Ca2+-mediated PDP activation has not been studied. In this work, we investigated the Ca2+ sensitivity of two recombinant PDPs from the protozoan human parasites Trypanosoma cruzi (TcPDP) and T. brucei (TbPDP) and generated a TcPDP-KO cell line to establish TcPDP's role in cell bioenergetics and survival. Moreover, the mitochondrial localization of the TcPDP was studied by CRISPR/Cas9-mediated endogenous tagging. Our results indicate that TcPDP and TbPDP both are Ca2+-sensitive phosphatases. Of note, TcPDP-KO epimastigotes exhibited increased levels of phosphorylated TcPDH, slower growth and lower oxygen consumption rates than control cells, an increased AMP/ATP ratio and autophagy under starvation conditions, and reduced differentiation into infective metacyclic forms. Furthermore, TcPDP-KO trypomastigotes were impaired in infecting cultured host cells. We conclude that TcPDP is a Ca2+-stimulated mitochondrial phosphatase that dephosphorylates TcPDH and is required for normal growth, differentiation, infectivity, and energy metabolism in T. cruzi. Our results support the view that one of the main roles of the MCU is linked to the regulation of intramitochondrial dehydrogenases. (AU)

• Processo FAPESP: 13/50624-0 - Sinalização por íons de cálcio em tripanossomatídeos
• Beneficiário: Roberto Docampo
• Modalidade de apoio: Auxílio à Pesquisa - Programa SPEC
• Processo FAPESP: 14/08995-4 - Sinalização por íons de cálcio em tripanosomatídeos
• Beneficiário: Noelia Marina Lander Manfredi
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/13148-9 - Sinalização por íons de cálcio em tripanossomatídeos
• Beneficiário: Miguel Angel Chiurillo Siervo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado