title: The equatorial position of the metaphase plate ensures symmetric cell divisions.
abstract: Chromosome alignment in the middle of the bipolar spindle is a hallmark of metazoan cell divisions. When we offset the metaphase plate position by creating an asymmetric centriole distribution on each pole, we find that metaphase plates relocate to the middle of the spindle before anaphase. The spindle assembly checkpoint enables this centering mechanism by providing cells enough time to correct metaphase plate position. The checkpoint responds to unstable kinetochore-microtubule attachments resulting from an imbalance in microtubule stability between the two half-spindles in cells with an asymmetric centriole distribution. Inactivation of the checkpoint prior to metaphase plate centering leads to asymmetric cell divisions and daughter cells of unequal size; in contrast, if the checkpoint is inactivated after the metaphase plate has centered its position, symmetric cell divisions ensue. This indicates that the equatorial position of the metaphase plate is essential for symmetric cell divisions.
authors.affiliation: Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland.
authors.forename: Chia Huei
authors.identifier: http://orcid.org/0000-0002-5561-6246
authors.initials: CH
authors.lastname: Tan
authors.affiliation: Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland.
authors.forename: Ivana
authors.initials: I
authors.lastname: Gasic
authors.affiliation: Institute of Biochemistry, ETH Zurich, Zurich, Switzerland.
authors.forename: Sabina P
authors.initials: SP
authors.lastname: Huber-Reggi
authors.affiliation: Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland.
authors.forename: Damian
authors.initials: D
authors.lastname: Dudka
authors.affiliation: Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
authors.forename: Marin
authors.initials: M
authors.lastname: Barisic
authors.affiliation: Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
authors.forename: Helder
authors.initials: H
authors.lastname: Maiato
authors.affiliation: Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Meraldi
mesh_terms: D000705:Anaphase; D048429:Cell Size; D004847:Epithelial Cells / Q000166:cytology*; D006367:HeLa Cells; D006801:Humans; D008677:Metaphase; D008941:Spindle Apparatus / Q000378:metabolism*
keywords: cell biology; cell division; centrosome; human; kinetochore; mitosis; spindle; spindle assembly checkpoint