title: Cell division plane orientation based on tensile stress in Arabidopsis thaliana.
abstract: Cell geometry has long been proposed to play a key role in the orientation of symmetric cell division planes. In particular, the recently proposed Besson-Dumais rule generalizes Errera's rule and predicts that cells divide along one of the local minima of plane area. However, this rule has been tested only on tissues with rather local spherical shape and homogeneous growth. Here, we tested the application of the Besson-Dumais rule to the divisions occurring in the Arabidopsis shoot apex, which contains domains with anisotropic curvature and differential growth. We found that the Besson-Dumais rule works well in the central part of the apex, but fails to account for cell division planes in the saddle-shaped boundary region. Because curvature anisotropy and differential growth prescribe directional tensile stress in that region, we tested the putative contribution of anisotropic stress fields to cell division plane orientation at the shoot apex. To do so, we compared two division rules: geometrical (new plane along the shortest path) and mechanical (new plane along maximal tension). The mechanical division rule reproduced the enrichment of long planes observed in the boundary region. Experimental perturbation of mechanical stress pattern further supported a contribution of anisotropic tensile stress in division plane orientation. Importantly, simulations of tissues growing in an isotropic stress field, and dividing along maximal tension, provided division plane distributions comparable to those obtained with the geometrical rule. We thus propose that division plane orientation by tensile stress offers a general rule for symmetric cell division in plants.
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure (ENS) de Lyon, Université Claude Bernard (UCB) Lyon 1, CNRS, Institut National de la Recherche Agronomique, F-69342 Lyon, France; Laboratoire Joliot-Curie, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France;
authors.forename: Marion
authors.initials: M
authors.lastname: Louveaux
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure (ENS) de Lyon, Université Claude Bernard (UCB) Lyon 1, CNRS, Institut National de la Recherche Agronomique, F-69342 Lyon, France; Laboratoire Joliot-Curie, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France; Laboratoire de Physique, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France.
authors.forename: Jean-Daniel
authors.initials: JD
authors.lastname: Julien
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure (ENS) de Lyon, Université Claude Bernard (UCB) Lyon 1, CNRS, Institut National de la Recherche Agronomique, F-69342 Lyon, France; Laboratoire Joliot-Curie, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France;
authors.forename: Vincent
authors.initials: V
authors.lastname: Mirabet
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure (ENS) de Lyon, Université Claude Bernard (UCB) Lyon 1, CNRS, Institut National de la Recherche Agronomique, F-69342 Lyon, France; Laboratoire Joliot-Curie, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France; olivier.hamant@ens-lyon.fr arezki.boudaoud@ens-lyon.fr.
authors.forename: Arezki
authors.initials: A
authors.lastname: Boudaoud
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure (ENS) de Lyon, Université Claude Bernard (UCB) Lyon 1, CNRS, Institut National de la Recherche Agronomique, F-69342 Lyon, France; Laboratoire Joliot-Curie, CNRS, ENS de Lyon, UCB Lyon 1, Université de Lyon, 69364 Lyon, Cedex 07, France; olivier.hamant@ens-lyon.fr arezki.boudaoud@ens-lyon.fr.
authors.forename: Olivier
authors.initials: O
authors.lastname: Hamant
mesh_terms: D000465:Algorithms; D017360:Arabidopsis / Q000166:cytology*; D002455:Cell Division; D019070:Cell Lineage; D048430:Cell Shape; D018519:Meristem / Q000166:cytology*; D018613:Microscopy, Confocal; D008954:Models, Biological; D018520:Plant Shoots / Q000166:cytology*; D013314:Stress, Mechanical
keywords: Arabidopsis; cell division plane; mechanical forces; meristem; vertex model