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Phosphoinositide-mediated ring anchoring resists perpendicular forces to promote medial cytokinesis.

ABSTRACT: Many eukaryotic cells divide by assembling and constricting an actin- and myosin-based contractile ring (CR) that is physically linked to the plasma membrane (PM). In this study, we report that Schizosaccharomyces pombe cells lacking efr3, which encodes a conserved PM scaffold for the phosphatidylinositol-4 kinase Stt4, build CRs that can slide away from the cell middle during anaphase in a myosin V-dependent manner. The Efr3-dependent CR-anchoring mechanism is distinct from previously reported pathways dependent on the Fes/CIP4 homology Bin-Amphiphysin-Rvs167 (F-BAR) protein Cdc15 and paxillin Pxl1. In efr3?, the concentrations of several membrane-binding proteins were reduced in the CR and/or on the PM. Our results suggest that proper PM lipid composition is important to stabilize the central position of the CR and resist myosin V-based forces to promote the fidelity of cell division.

SUBMITTER: Snider CE

PROVIDER: S-EPMC5626552 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Phosphoinositide-mediated ring anchoring resists perpendicular forces to promote medial cytokinesis.

Snider Chloe E CE Willet Alaina H AH Chen Jun-Song JS Arpağ Göker G Zanic Marija M Gould Kathleen L KL

The Journal of cell biology 20170807 10

Many eukaryotic cells divide by assembling and constricting an actin- and myosin-based contractile ring (CR) that is physically linked to the plasma membrane (PM). In this study, we report that <i>Schizosaccharomyces pombe</i> cells lacking <i>efr3</i>, which encodes a conserved PM scaffold for the phosphatidylinositol-4 kinase Stt4, build CRs that can slide away from the cell middle during anaphase in a myosin V-dependent manner. The Efr3-dependent CR-anchoring mechanism is distinct from previo ...[more]

PMID: 28784611

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