title: Sec6/8 complex is recruited to cell-cell contacts and specifies transport vesicle delivery to the basal-lateral membrane in epithelial cells.
abstract: In budding yeast, the Sec6/8p complex is essential for generating cell polarity by specifying vesicle delivery to the bud tip. We show that Sec6/8 homologs are components of a cytosolic, approximately 17S complex in nonpolarized MDCK epithelial cells. Upon initiation of calcium-dependent cell-cell adhesion, approximately 70% of Sec6/8 is rapidly (t(1/2) approximately 3-6 hr) recruited to sites of cell-cell contact. In streptolysin-O-permeabilized MDCK cells, Sec8 antibodies inhibit delivery of LDL receptor to the basal-lateral membrane, but not p75NTR to the apical membrane. These results indicate that lateral membrane recruitment of the Sec6/8 complex is a consequence of cell-cell adhesion and is essential for the biogenesis of epithelial cell surface polarity.
authors.affiliation: Department of Molecular and Cellular Physiology, Stanford University School of Medicine, California 94305-5345, USA.
authors.forename: K K
authors.initials: KK
authors.lastname: Grindstaff
authors.forename: C
authors.initials: C
authors.lastname: Yeaman
authors.forename: N
authors.initials: N
authors.lastname: Anandasabapathy
authors.forename: S C
authors.initials: SC
authors.lastname: Hsu
authors.forename: E
authors.initials: E
authors.lastname: Rodriguez-Boulan
authors.forename: R H
authors.initials: RH
authors.lastname: Scheller
authors.forename: W J
authors.initials: WJ
authors.lastname: Nelson
mesh_terms: D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002451:Cell Compartmentation; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity / Q000502:physiology*; D004285:Dogs; D004847:Epithelial Cells / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism; D007365:Intercellular Junctions / Q000502:physiology*; D007425:Intracellular Membranes / Q000378:metabolism; D007668:Kidney / Q000166:cytology; D008077:Lipoproteins, LDL / Q000378:metabolism; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000378:metabolism; D011485:Protein Binding
chemical_list: D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D008077:Lipoproteins, LDL; D009414:Nerve Growth Factors