gp63 Homologues inTrypanosoma cruzi: Surface Antigens with Metalloprotease Activity and a Possible Role in Host Cell Infection

Abstract

gp63 is a highly abundant glycosylphosphatidylinositol (GPI)-anchored membrane protein expressed predominantly in the promastigote but also in the amastigote stage of Leishmania species. In Leishmania spp., gp63 has been implicated in a number of steps in establishment of infection. Here we demonstrate that Trypanosoma cruzi, the etiological agent of Chagas' disease, has a family of gp63 genes composed of multiple groups. Two of these groups, Tcgp63-I and -II, are present as high-copy-number genes. The genomic organization and mRNA expression pattern were specific for each group. Tcgp63-I was widely expressed, while the Tcgp63-II group was scarcely detected in Northern blots, even though it is well represented in the T. cruzi genome. Western blots using sera directed against a synthetic peptide indicated that the Tcgp63-I group produced proteins of ϳ78 kDa, differentially expressed during the life cycle. Immunofluorescence staining and phosphatidylinositol-specific phospholipase C digestion confirmed that Tcgp63-I group members are surface proteins bound to the membrane by a GPI anchor. We also demonstrate the presence of metalloprotease activity which is attributable, at least in part, to Tcgp63-I group. Since antibodies against Tcgp63-I partially blocked infection of Vero cells by trypomastigotes, a possible role for this group in infection is suggested.

Proteomic analysis reveals different composition of extracellular vesicles released by two Trypanosoma cruzi strains associated with their distinct interaction with host cells

“…Previous studies already showed that the gp63 from T. cruzi has a key role in parasite infection [3] and complement inhibition [55]. We identified 7 clusters of this protein, and most of the hits were found in the EVs from Y strain.…”

“…Trypanosoma cruzi cell surface is covered by a wide range of molecules including members of trans -sialidase (TS/gp85), mucin-like glycoproteins, mucin-associated proteins (MASP) superfamilies, and proteases [1–3]. Those molecules are involved in attachment and invasion to the host’s cell by infective forms of the parasite [4–6].…”

Biological Roles of Peptidases in Trypanosomatids~!2009-11-26~!2010-02-15~!2010-03-18~!

“…In addition, multiple isoforms of the endopeptidase gp63 (clan MA, family M8) family have been found as well as matrix metallopeptidases-like peptidases [98,99]. Recently, exopeptidases such as metallocarboxypeptidases were found in the cytoplasm of the parasite [100,101].…”

“…cruzi expresses multiple isoforms of the gp63 family of metallopeptidases at all life stages [98]. A polyclonal antiserum against recombinant gp63 of T. cruzi (Tcgp63) was used as a tool in order to study Tcgp63 expression and localization in this parasite.…”

Novel Therapeutic Strategies for Chagas` Disease

“…Metallopeptidases homologous to the gp63 of Leishmania spp. are present in T. cruzi, as well as two metallocarboxypeptidases belonging to the M32 family, before found only in prokaryotes (Bonaldo, 1991;Lowndes, 1996;Burleigh, 2002;Cuevas, 2003;Nogueira de Melo, 2004;Gutierrez, 2008;Niemirowicz, 2007;Niemirowicz, 2008;Kulkarni, 2009). The most abundant among these enzymes is cruzipain (Cz), also known as GP57/51 or cruzain (the recombinant catalytic domain of cruzipain) a cysteine peptidase (CP) expressed as a mixture of isoforms.…”