Apical sorting by galectin-3-dependent glycoprotein clustering
Författare
Summary, in English
Epithelial cells are characterized by their polarized organization based on an apical membrane that is separated from the basolateral membrane domain by tight junctions. Maintenance of this morphology is guaranteed by highly specific sorting machinery that separates lipids and proteins into different carrier populations for the apical or basolateral cell surface. Lipid-raft-independent apical carrier vesicles harbour the beta-galactoside-binding lectin galectin-3, which interacts directly with apical cargo in a glycan-dependent manner. These glycoproteins are mistargeted to the basolateral membrane in galectin-3-depleted cells, dedicating a central role to this lectin in raft-independent sorting as apical receptor. Here, we demonstrate that high-molecular-weight clusters are exclusively formed in the presence of galectin-3. Their stability is sensitive to increased carbohydrate concentrations, and cluster formation as well as apical sorting are perturbed in glycosylation-deficient Madin-Darby canine kidney (MDCK) II cells. Together, our data suggest that glycoprotein cross-linking by galectin-3 is required for apical sorting of non-raft-associated cargo.
Publiceringsår
2007
Språk
Engelska
Sidor
379-388
Publikation/Tidskrift/Serie
Traffic: the International Journal of Intracellular Transport
Volym
8
Issue
4
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Microbiology in the medical area
- Immunology in the medical area
Nyckelord
- polarized cells
- glycoprotein sorting
- apical transport
- galectin
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1398-9219