title: Modulation of phosphatidylinositol 4-phosphate levels by CaBP7 controls cytokinesis in mammalian cells.
abstract: Calcium and phosphoinositide signaling regulate cell division in model systems, but their significance in mammalian cells is unclear. Calcium-binding protein-7 (CaBP7) is a phosphatidylinositol 4-kinaseIIIβ (PI4KIIIβ) inhibitor required during cytokinesis in mammalian cells, hinting at a link between these pathways. Here we characterize a novel association of CaBP7 with lysosomes that cluster at the intercellular bridge during cytokinesis in HeLa cells. We show that CaBP7 regulates lysosome clustering and that PI4KIIIβ is essential for normal cytokinesis. CaBP7 depletion induces lysosome mislocalization, extension of intercellular bridge lifetime, and cytokinesis failure. These data connect phosphoinositide and calcium pathways to lysosome localization and normal cytokinesis in mammalian cells.
authors.affiliation: Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom.
authors.forename: Dayani
authors.initials: D
authors.lastname: Rajamanoharan
authors.affiliation: Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom.
authors.forename: Hannah V
authors.initials: HV
authors.lastname: McCue
authors.affiliation: Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Burgoyne
authors.affiliation: Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom leeh@liv.ac.uk.
authors.forename: Lee P
authors.initials: LP
authors.lastname: Haynes
mesh_terms: D002135:Calcium-Binding Proteins / Q000502:physiology*; D048749:Cytokinesis / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D008247:Lysosomes / Q000502:physiology*; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: C540140:CABP7 protein, human; D002135:Calcium-Binding Proteins; D018129:Phosphatidylinositol Phosphates; C037178:phosphatidylinositol 4-phosphate