English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/8153
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar otros formatos: Exportar EndNote (RIS)Exportar EndNote (RIS)Exportar EndNote (RIS)
Título : MAL, an integral element of the apical sorting machinery, is an itinerant protein that cycles between the trans-Golgi network and the plasma membrane
Autor : Puertollano, Rosa; Alonso, Miguel A.
Palabras clave : MAL proteins
Fecha de publicación : 1999
Editor: American Society for Cell Biology
Citación : Molecular Biology of the Cell, Vol. 10, Issue 10, 3435-3447 (1999)
Resumen: The MAL proteolipid is a nonglycosylated integral membrane protein found in glycolipid-enriched membrane microdomains. In polarized epithelial Madin-Darby canine kidney cells, MAL is necessary for normal apical transport and accurate sorting of the influenza virus hemagglutinin. MAL is thus part of the integral machinery for glycolipid-enriched membrane-mediated apical transport. At steady state, MAL is predominantly located in perinuclear vesicles that probably arise from the trans-Golgi network (TGN). To act on membrane traffic and to prevent their accumulation in the target compartment, integral membrane elements of the protein-sorting machinery should be itinerant proteins that cycle between the donor and target compartments. To establish whether MAL is an itinerant protein, we engineered the last extracellular loop of MAL by insertion of sequences containing the FLAG epitope or with sequences containing residues that became O-glycosylated within the cells or that displayed biotinylatable groups. The ectopic expression of these modified MAL proteins allowed us to investigate the surface expression of MAL and its movement through different compartments after internalization with the use of a combination of assays, including surface biotinylation, surface binding of anti-FLAG antibodies, neuraminidase sensitivity, and drug treatments. Immunofluorescence and flow cytometric analyses indicated that, in addition to its Golgi localization, MAL was also expressed on the cell surface, from which it was rapidly internalized. This retrieval implies transport through the endosomal pathway and requires endosomal acidification, because it can be inhibited by drugs such as chloroquine, monensin, and NH4Cl. Resialylation experiments of surface MAL treated with neuraminidase indicated that ~30% of the internalized MAL molecules were delivered to the TGN, probably to start a new cycle of cargo transport. Together, these observations suggest that, as predicted for integral membrane members of the late protein transport machinery, MAL is an itinerant protein cycling between the TGN and the plasma membrane
Versión del editor: http://www.molbiolcell.org/cgi/content/abstract/10/10/3435
URI : http://hdl.handle.net/10261/8153
ISSN: 1059-1524 (print)
1939-4586 (online)
Aparece en las colecciones: (CBM) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
RPuertollano_MolBiolCell_3435.pdf670,15 kBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.