title: P-selectin binds to the D'-D3 domains of von Willebrand factor in Weibel-Palade bodies.
abstract: It has recently been shown that the ultralarge platelet-recruiting von Willebrand factor (VWF) strings formed immediately at exocytosis from endothelial cells may be anchored to the cell surface by interaction with the integral membrane protein P-selectin. This finding of a new binding partner for VWF immediately prompts the question which domains of VWF bind to P-selectin. We have exploited the fact that VWF expression in HEK293 cells triggers the formation of Weibel-Palade body-like structures that can recruit P-selectin. A suitably modified version of this assay using coexpressed truncations of VWF, together with P-selectin variants in HEK293 cells, allowed us to determine which domains of VWF would recruit P-selectin within a physiologically appropriate intracellular environment. Confirming the results of such a cellular assay by conventional coimmunoprecipitation, we concluded that the lumenal domain of P-selectin interacts with the D'-D3 domains of VWF.
authors.affiliation: MRC Laboratory for Molecular Cell Biology, Cell Biology Unit and Department of Biochemistry, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Grégoire
authors.initials: G
authors.lastname: Michaux
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Pullen
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Haberichter
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Cutler
mesh_terms: D001665:Binding Sites; D002460:Cell Line; D006801:Humans; D007668:Kidney; D019007:P-Selectin / Q000378:metabolism*; D020302:Weibel-Palade Bodies / Q000378:metabolism*; D014841:von Willebrand Factor / Q000737:chemistry / Q000378:metabolism*
chemical_list: D019007:P-Selectin; D014841:von Willebrand Factor