INVESTIGADORES
MALETTO Belkys AngÉlica
artículos
Título:
Adaptor protein 2 regulates receptor-mediated endocytosis and cyst formation in Giardia lamblia
Autor/es:
MARIA R. RIVERO, CECILIA V. VRANYCH, MARIANO BISBAL, BELKYS A. MALETTO, ANDREA S. ROPOLO AND MARIA C. TOUZ
Revista:
BIOCHEMICAL JOURNAL
Editorial:
PORTLAND PRESS LTD
Referencias:
Año: 2010 p. 33 - 45
ISSN:
0264-6021
Resumen:
The parasite Giardia lamblia possesses PVs (peripheral vacuoles)
that function as both endosomes and lysosomes and are implicated
in the adaptation, differentiation and survival of the parasite
in different environments. The mechanisms by which Giardia
traffics essential proteins to these organelles and regulates their
secretion have important implications in the control of parasite
dissemination. In the present study, we describe the participation
of the heterotetrameric clathrin-adaptor protein gAP2 (Giardia
adaptor protein 2) complex in lysosomal protein trafficking.
A specific monoclonal antibody against the medium subunit
(gμ2) of gAP2 showed localization of this complex to the PVs,
cytoplasm and plasma membrane in the growing trophozoites.
gAP2 also co-localized with clathrin in the PVs, suggesting its
involvement in endocytosis. Uptake experiments using standard
molecules for the study of endocytosis revealed that gAP2
specifically participated in the endocytosis of LDL (low-density
lipoprotein). Targeted down-regulation of the gene encoding gμ2
in growing and encysting trophozoites resulted in a large decrease
in the amount of cell growth and cyst wall formation, suggesting
a distinct mechanism in which gAP2 is directly involved in both
endocytosis and vesicular trafficking.