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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-kinaseIII? (PI4KIII?) 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 PI4KIII? 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.

SUBMITTER: Rajamanoharan D

PROVIDER: S-EPMC4395124 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Modulation of phosphatidylinositol 4-phosphate levels by CaBP7 controls cytokinesis in mammalian cells.

Rajamanoharan Dayani D McCue Hannah V HV Burgoyne Robert D RD Haynes Lee P LP

Molecular biology of the cell 20150225 8

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 clus ...[more]

PMID: 25717182

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