title: Type II PI4-kinases control Weibel-Palade body biogenesis and von Willebrand factor structure in human endothelial cells.
abstract: Weibel-Palade bodies (WPBs) are endothelial storage organelles that mediate the release of molecules involved in thrombosis, inflammation and angiogenesis, including the pro-thrombotic glycoprotein von Willebrand factor (VWF). Although many protein components required for WPB formation and function have been identified, the role of lipids is almost unknown. We examined two key phosphatidylinositol kinases that control phosphatidylinositol 4-phosphate levels at the trans-Golgi network, the site of WPB biogenesis. RNA interference of the type II phosphatidylinositol 4-kinases PI4KIIα and PI4KIIβ in primary human endothelial cells leads to formation of an increased proportion of short WPB with perturbed packing of VWF, as exemplified by increased exposure of antibody-binding sites. When stimulated with histamine, these cells release normal levels of VWF yet, under flow, form very few platelet-catching VWF strings. In PI4KIIα-deficient mice, immuno-microscopy revealed that VWF packaging is also perturbed and these mice exhibit increased blood loss after tail cut compared to controls. This is the first demonstration that lipid kinases can control the biosynthesis of VWF and the formation of WPBs that are capable of full haemostatic function.
authors.affiliation: Endothelial Cell Biology Laboratory, University College London, London WC1E 6BT, UK.
authors.forename: Mafalda
authors.initials: M
authors.lastname: Lopes da Silva
authors.affiliation: Endothelial Cell Biology Laboratory, University College London, London WC1E 6BT, UK.
authors.forename: Marie N
authors.initials: MN
authors.lastname: O'Connor
authors.affiliation: Bioinformatics Image Core, University College London, London WC1E 6BT, UK.
authors.forename: Janos
authors.initials: J
authors.lastname: Kriston-Vizi
authors.affiliation: Electron Microscopy Core, MRC Laboratory of Molecular Cell Biology, University College London, London WC1E 6BT, UK.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: White
authors.affiliation: Royal Free Centre for Biomedical Science, and Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London NW3 2PF, UK.
authors.forename: Raya
authors.initials: R
authors.lastname: Al-Shawi
authors.affiliation: Royal Free Centre for Biomedical Science, and Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London NW3 2PF, UK.
authors.forename: J Paul
authors.initials: JP
authors.lastname: Simons
authors.affiliation: Leibniz Institut für Molekulare Pharmakologie (FMP), Molecular Physiology and Cell Biology, Robert-Roessle-Str. 10, 13125 Berlin Fachbereich Biologie, Chemie, Pharmazie, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Mössinger
authors.affiliation: Leibniz Institut für Molekulare Pharmakologie (FMP), Molecular Physiology and Cell Biology, Robert-Roessle-Str. 10, 13125 Berlin Fachbereich Biologie, Chemie, Pharmazie, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Haucke
authors.affiliation: Endothelial Cell Biology Laboratory, University College London, London WC1E 6BT, UK d.cutler@ucl.ac.uk.
authors.forename: Daniel F
authors.identifier: 0000-0002-4288-7530
authors.initials: DF
authors.lastname: Cutler
mesh_terms: D000818:Animals; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D005089:Exocytosis; D005786:Gene Expression Regulation; D006632:Histamine / Q000008:administration & dosage; D006801:Humans; D007249:Inflammation / Q000235:genetics / Q000473:pathology; D008055:Lipids / Q000235:genetics; D051379:Mice; D015778:Minor Histocompatibility Antigens / Q000235:genetics*; D009389:Neovascularization, Pathologic / Q000235:genetics; D018129:Phosphatidylinositol Phosphates / Q000235:genetics / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000037:antagonists & inhibitors / Q000235:genetics*; D034622:RNA Interference; D013927:Thrombosis / Q000235:genetics / Q000473:pathology; D020302:Weibel-Palade Bodies / Q000235:genetics / Q000378:metabolism*; D021601:trans-Golgi Network / Q000235:genetics / Q000378:metabolism; D014841:von Willebrand Factor / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D008055:Lipids; D015778:Minor Histocompatibility Antigens; D018129:Phosphatidylinositol Phosphates; C037178:phosphatidylinositol 4-phosphate; D014841:von Willebrand Factor; D006632:Histamine; D017853:Phosphotransferases (Alcohol Group Acceptor); C402182:phosphatidylinositol phosphate 4-kinase
keywords: Phosphatidylinositol 4-kinase alpha; Phosphatidylinositol 4-kinase beta; Von Willebrand factor; Weibel-Palade body