EPIMASTIGOTE PROTEIN EXPRESSION OF THE TRYPANOSOMA CRUZI CYCLOPHILIN GENE FAMILY

POTENZA, MARIANA., RUIZ, A., MARÍN, M., DURAN, R. AND BÚA, J

Iguazú, Argentina

Congreso; XL Reunión Anual de la Sociedad Argentina de Bioquímica y Biología Molecular; 2004

Sociedad Argentina de Bioquímica y Biología Molecular

The immunosuppressive peptide Cyclosporin A (CsA) has anti-parasitic effect against several protozoans, and was also demonstrated for Trypanosoma cruzi (Búa et al, Bioorg. & Med. Chem. Lett., 2004, 14, 4633-37). The trypanocidal effect is  probably exerted through the formation of a specific complex with Cyclophilins (CyPs), which are a multigenic family of enzymes that mediate cellular folding events, acting as chaperones. There are twelve genes that codify for CyPs in this parasite, though some of them are divergent in their CsA binding domain. Seven genes appeared to be orthologues of other trypanosomatid cyclophilins according to epimastigote Expressed Sequence Tags annotation in the T. cruzi Genome Project. By means of RT-PCR amplification experiments, this seven genes also proved to be transcribed in amastigotes and trypomastigotes. Expressed CsA binding proteins were purified by affinity chromatography. Four protein bands were detected by silver staining after running the eluate on an acrylamide gel. These spots were analysed by MALDI-TOF mass spectrometry after in-gel tryptic digestion. Database searching using peptide mass fingerprints allowed the identification of T. cruzi cyclophilins of 19, 21, 28 and 40 kDa, being the most expressed TcCyP19. We conclude that these four cyclophilins are actively expressed in the epimatigote stage of Trypanosoma cruzi.