Molecular characterization and interactome analysis of Trypanosoma cruzi Tryparedoxin 1

PIÑEYRO, MARÍA DOLORES; PARODI-TALICE, ADRIANA; PORTELA, MAGDALENA; ARIAS, DIEGO G.; GUERRERO, SERGIO A.; ROBELLO, CARLOS

JOURNAL OF PROTEOMICS

ELSEVIER SCIENCE BV

Lugar: 74(9): 1683-92; Año: 2011 vol. 74 p. 1683 - 1692

1874-3919

Trypanosoma cruzi tryparedoxin 1 (TcTXN1) is an oxidoreductase belonging to the thioredoxinsuperfamily, whichmediates electron transfer between trypanothione and peroxiredoxins. Intrypanosomes TXNs, and not thioredoxins, constitute the oxido-reductases of peroxiredoxins.Since, to date, there is no information concerning TcTXN1 substrates in T. cruzi, the aimof thiswork was to characterize TcTXN1 in two aspects: expression throughout T. cruzi life cycle andsubcellular localization; and the study of TcTXN1 interacting-proteins. We demonstrate thatTcTXN1 is a cytosolic and constitutively expressed protein in T. cruzi. In order to start to unravelthe redox interactome of T. cruzi we designed an active site mutant protein lacking theresolving cysteine, and validated the complex formation in vitro between the mutated TcTXN1and a known partner, the cytosolic peroxiredoxin. Through the expression of this mutantprotein in parasites with an additional 6xHis-tag, heterodisulfide complexes were isolated byaffinity chromatography and identified by 2-DE/MS. This allowed us to identify fifteen TcTXN1proteins which are involved in two main processes: oxidative metabolism and proteinsynthesis and degradation. Our approach led us to the discovery of several putatively TcTXN1-interacting proteins thereby contributing to our understanding of the redox interactome of T.cruzi.