Functional analysis and importance for host cell infection of the Ca2+-conducting subunits of the mitochondrial calcium uniporter of Trypanosoma cruzi

Author(s)

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

Affiliation

^[1] Univ Georgia, Ctr Trop & Emerging Global Dis, Athens, GA 30602 - USA

^[2] Univ Georgia, Dept Cellular Biol, Athens, GA 30602 - USA

^[3] Univ Estadual Campinas, Dept Patol Clin, Fac Ciencias Med, BR-13083 Campinas, SP - Brazil

• Document type: Journal article
• Source: MOLECULAR BIOLOGY OF THE CELL; v. 30, n. 14, p. 1676-1690, JUL 1 2019.
• Web of Science Citations: 1

Abstract

We report here that Trypanosoma cruzi, the etiologic agent of Chagas disease, possesses two unique paralogues of the mitochondrial calcium uniporter complex TcMCU subunit that we named TcMCUc and TcMCUd. The predicted structure of the proteins indicates that, as predicted for the TcMCU and TcMCUb paralogues, they are composed of two helical membrane-spanning domains and contain a WDXXEPXXY motif. Overexpression of each gene led to a significant increase in mitochondrial Ca2+ uptake, while knockout (KO) of either TcMCUc or TcMCUd led to a loss of mitochondrial Ca2+ uptake, without affecting the mitochondrial membrane potential. TcMCUc-KO and TcMCUd-KO epimastigotes exhibited reduced growth rate in low-glucose medium and alterations in their respiratory rate, citrate synthase activity, and AMP/ATP ratio, while trypomastigotes had reduced ability to efficiently infect host cells and replicate intracellularly as amastigotes. By gene complementation of KO cell lines or by a newly developed CRISPR/Cas9-mediated knock-in approach, we also studied the importance of critical amino acid residues of the four paralogues on mitochondrial Ca2+ uptake. In conclusion, the results predict a hetero-oligomeric structure for the T. cruzi MCU complex, with structural and functional differences, as compared with those in the mammalian complex. (AU)

• FAPESP's process: 14/08995-4 - Calcium signaling in trypanosomatids
• Grantee: Noelia Marina Lander Manfredi
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/13148-9 - Calcium signaling in trypanosomatids
• Grantee: Miguel Angel Chiurillo Siervo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/25709-8 - Functional study of MICU1 and MICU2 proteins involved in Trypanosoma cruzi calcium signaling
• Grantee: Mayara Santos Bertolini
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 13/50624-0 - Calcium signaling in trypanosomatids
• Grantee: Roberto Docampo
• Support Opportunities: Research Projects - SPEC Program