INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
The traffic of Solubles Hydrolases is mediated by gVps10p-like receptor in Giardia lamblia.
Autor/es:
MIRAS S. L; RIVERO M.R; ZAMPONI N.; FELIZIANI C.; ROPOLO A.S; TOUZ M. C.
Lugar:
San Luis
Reunión:
Congreso; 47th Annual Meeting. Argentine Society for Biochemistry and Molecular Biology Research; 2011
Institución organizadora:
SOCIEDAD ARGENTINA DE INVESTIGACION EN BIOQUIMICA Y BIOLOGIA MOLECULAR
Resumen:
The targeting of lysosomal
enzymes to their final destination is directed by a series of protein and
recognition signals. Although, Giardialamblia lacks a recognized Golgi
apparatus or a typical endosome/lysosome system, it might have a specific and
conserved mechanism by means the soluble hydrolases are sorted. In this work,
we describe the presence of a Vps10p -like receptor and its function in sorting
of lysosomal enzymes. By bioinformatics
and proteinase K assays allowed us to determine that the gVps10p receptor is a
type I transmembrana protein with a WD40 motif in the luminal portion and a
cytoplasmic tyrosine motif (YQII). Immunoblot assay showed a 60 kDa but also a 120 kDa band, possibly related
with a dimerization. IFA and confocal
microscopy of trophozoites expressing gVps10p-HA fusion protein, showed that it
localize around the nuclei colocalizing with the endoplasmic reticulum marker
BIP (Immunoglobulin Binding Protein). Co-expression of gVPS10p-HA and gAcPh-V5 fusion
proteins showed colocalization around nuclei and in the lysosomal peripheral
vacuoles. On other hand, gVps10p-YQII-HA fusion protein, lacking the
cytoplasmic tyrosine motif, showed a different subcelular distribution possibly
related with changes in protein trafficking. This work will contribute to
understand how the endosomal/lysosomal pathway works in the early divergent
parasite Giardia lamblia.