INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Vacuolar protein sorting receptor: new molecular evidence of a sorting pathway in Giardia lamblia.
Autor/es:
MIRAS S; RIVERO MR; FELIZIANI C; ZAMPONI N; QUIROGA R; ROPOLO AS; TOUZ MC
Lugar:
Mendoza
Reunión:
Congreso; SAIB; 2012
Resumen:
In , lysosome-like peripheral vacuoles (PVs) need to specifically coordinate their endosomal and lysosomal functions to be able to successfully perform endocytosis, protein degradation and protein delivery, but how cargo, ligands and molecular components generate specific routes to the PVs remains poorly understood. Recently, we found that delivering membrane Cathepsin C and the soluble acid phosphatase (AcPh) to the PVs is adaptin (AP1)- dependent. However, the receptor that links AcPh and AP1 was never described.We have studied protein-binding to AcPh by using H6-taggedAcPh, and found that a membrane protein interacted with AcPh. This protein, named GlVps (for Giardia lamblia Vacuolar protein sorting), mainly localized to the ER-nuclear envelope and in some PVs, probably function as the sorting receptor for AcPh. The tyrosine-binding motif found in the C-terminal cytoplasmic tail domain of GlVps was essential for its exit from the endoplasmic reticulum and transport to the vacuoles, with this motif being necessary for the interaction with the medium subunit of AP1. Thus, the mechanism by which soluble proteins, such as AcPh, reach the peripheral vacuoles in appears to be very similar to the mechanism of lysosomal protein-sorting in more evolved eukaryotic cells.