[PMID]: | 28800609 |
[Au] Autor: | Cámara MLM; Cánepa GE; Lantos AB; Balouz V; Yu H; Chen X; Campetella O; Mucci J; Buscaglia CA |
[Ad] Endereço: | Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECh), Universidad Nacional de San Martín (UNSAM) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina. |
[Ti] Título: | The Trypomastigote Small Surface Antigen (TSSA) regulates Trypanosoma cruzi infectivity and differentiation. |
[So] Source: | PLoS Negl Trop Dis;11(8):e0005856, 2017 Aug. |
[Is] ISSN: | 1935-2735 |
[Cp] País de publicação: | United States |
[La] Idioma: | eng |
[Ab] Resumo: | BACKGROUND: TSSA (Trypomastigote Small Surface Antigen) is an antigenic, adhesion molecule displayed on the surface of Trypanosoma cruzi trypomastigotes. TSSA displays substantial sequence identity to members of the TcMUC gene family, which code for the trypomastigote mucins (tGPI-mucins). In addition, TSSA bears sequence polymorphisms among parasite strains; and two TSSA variants expressed as recombinant molecules (termed TSSA-CL and TSSA-Sy) were shown to exhibit contrasting features in their host cell binding and signaling properties. METHODS/PRINCIPLE FINDINGS: Here we used a variety of approaches to get insights into TSSA structure/function. We show that at variance with tGPI-mucins, which rely on their extensive O-glycoslylation to achieve their protective function, TSSA seems to be displayed on the trypomastigote coat as a hypo-glycosylated molecule. This has a functional correlate, as further deletion mapping experiments and cell binding assays indicated that exposition of at least two peptidic motifs is critical for the engagement of the 'adhesive' TSSA variant (TSSA-CL) with host cell surface receptor(s) prior to trypomastigote internalization. These motifs are not conserved in the 'non-adhesive' TSSA-Sy variant. We next developed transgenic lines over-expressing either TSSA variant in different parasite backgrounds. In strict accordance to recombinant protein binding data, trypomastigotes over-expressing TSSA-CL displayed improved adhesion and infectivity towards non-macrophagic cell lines as compared to those over-expressing TSSA-Sy or parental lines. These phenotypes could be specifically counteracted by exogenous addition of peptides spanning the TSSA-CL adhesion motifs. In addition, and irrespective of the TSSA variant, over-expression of this molecule leads to an enhanced trypomastigote-to-amastigote conversion, indicating a possible role of TSSA also in parasite differentiation. CONCLUSION/SIGNIFICANCE: In this study we provided novel evidence indicating that TSSA plays an important role not only on the infectivity and differentiation of T. cruzi trypomastigotes but also on the phenotypic variability displayed by parasite strains. |
[Mh] Termos MeSH primário: |
Antígenos de Protozoários/química Antígenos de Superfície/química Mucinas/metabolismo Trypanosoma cruzi/patogenicidade
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[Mh] Termos MeSH secundário: |
Sequência de Aminoácidos Animais Antígenos de Protozoários/genética Antígenos de Superfície/genética Diferenciação Celular Cercopithecus aethiops Doença de Chagas/parasitologia Regulação da Expressão Gênica Genes de Protozoários Células HeLa Seres Humanos Proteínas Recombinantes/química Trypanosoma cruzi/genética Células Vero
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[Pt] Tipo de publicação: | JOURNAL ARTICLE |
[Nm] Nome de substância:
| 0 (Antigens, Protozoan); 0 (Antigens, Surface); 0 (Mucins); 0 (Recombinant Proteins) |
[Em] Mês de entrada: | 1709 |
[Cu] Atualização por classe: | 171108 |
[Lr] Data última revisão:
| 171108 |
[Sb] Subgrupo de revista: | IM |
[Da] Data de entrada para processamento: | 170812 |
[St] Status: | MEDLINE |
[do] DOI: | 10.1371/journal.pntd.0005856 |
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