Transferrin uptake may occur through detergent-resistant membrane domains at the cytopharynx of Trypanosoma cruzi epimastigote forms
Mem. Inst. Oswaldo Cruz
; 102(7): 871-876, Nov. 2007. ilus, graf
Artigo
em Inglês
| LILACS
| ID: lil-470360
Biblioteca responsável:
BR1.1
ABSTRACT
Uptake of transferrin by epimastigote forms of the protozoan Trypanosoma cruzi occurs mainly through a cytostome/ cytopharynx, via uncoated endocytic vesicles that bud off from the bottom of the cytopharynx. We have here examined whether detergent-resistant membrane (DRM) domains might be involved in this process. Purified whole cell membrane fractions were assayed for cholesterol levels and used in dot blot analyses. Detergent-resistant membrane markers (cholera B toxin and anti-flotillin-1 antibody) presented positive reaction by dot blots in cholesterol-rich/ protein-poor membrane sub-fractions. The positive dot blot fraction was submitted to lipid composition analysis, showing composition similar to that of raft fractions described for other eukaryotic cells. Immunofluorescence assays allowed the localization of punctual positive signal for flotillin-1, matching the precise cytostome/ cytopharynx location. These data were confirmed by immunofluorescence assays with the co-localization of flotillin-1 and the transferrin uptake site. Our data suggest that DRM domains occur and are integrated at the cytostome/ cytopharynx of T. cruzi epimastigotes, being the main route for transferrin uptake.
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Base de dados:
LILACS
Assunto principal:
Trypanosoma cruzi
/
Transferrina
/
Colesterol
/
Microdomínios da Membrana
/
Detergentes
/
Microtúbulos
Limite:
Animais
Idioma:
Inglês
Revista:
Mem. Inst. Oswaldo Cruz
Assunto da revista:
Medicina Tropical
/
Parasitologia
Ano de publicação:
2007
Tipo de documento:
Artigo
País de afiliação:
Brasil
Instituição/País de afiliação:
Fiocruz/BR
/
Universidade Federal do Rio de Janeiro/BR