INVESTIGADORES
TOUZ Maria Carolina
congresos y reuniones científicas
Título:
The traffic of soluble hydrolases is mediated by VPS10P-like receptor in Giardia lamblia.
Autor/es:
MIRAS S; RIVERO MR; QUIROGA R; ZAMPONI N; FELIZIANI C; ROPOLO AS; TOUZ MC
Reunión:
Congreso; SAIB; 2011
Resumen:
The targeting of lysosomal enzymes to their final destination is
directed by a series of protein and recognition signals. Although,
Giardia lamblia 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. 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 to 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 G. lamblia.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. 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 to 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 G. lamblia.G. lamblia.