title: Morphoelasticity in the development of brown algaEctocarpus siliculosus: from cell rounding to branching.
abstract: A biomechanical model is proposed for the growth of the brown algaEctocarpus siliculosusFeaturing ramified uniseriate filaments, this alga has two modes of growth: apical growth and intercalary growth with branching. Apical growth occurs upon the mitosis of a young cell at one extremity and leads to a new tip cell followed by a cylindrical cell, whereas branching mainly occurs when a cylindrical cell becomes rounded and swells, forming a spherical cell. Given the continuous interplay between cell growth and swelling, a poroelastic model combining osmotic pressure and volumetric growth is considered for the whole cell, cytoplasm and cell wall. The model recovers the morphogenetic transformations of mature cells: transformation of a cylindrical shape into spherical shape with a volumetric increase, and then lateral branching. Our simulations show that the poro-elastic model, including the Mooney-Rivlin approach for hyper-elastic materials, can correctly reproduce the observations. In particular, branching appears to be a plasticity effect due to the high level of tension created after the increase in volume of mature cells.
authors.affiliation: School of Manufacturing Science and Engineering, Southwest University of Science and Technology, Sichuan 621010, People's Republic of China.
authors.forename: Fei
authors.initials: F
authors.lastname: Jia
authors.affiliation: Laboratoire de Physique Statistique, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités UPMC Univ Paris 06, CNRS, 24 rue Lhomond, 75005 Paris, France benamar@lps.ens.fr.|Institut Universitaire de Cancérologie, Faculté de médecine, Université Pierre et Marie Curie-Paris 6, 91 Bd de l'Hôpital, 75013 Paris, France.
authors.forename: Martine
authors.identifier: 0000-0001-9132-2053
authors.initials: M
authors.lastname: Ben Amar
authors.affiliation: UMR8227 CNRS-UPMC, Station Biologique, Place George Teissier, 29680 Roscoff, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Billoud
authors.affiliation: UMR8227 CNRS-UPMC, Station Biologique, Place George Teissier, 29680 Roscoff, France.
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Charrier
mesh_terms: D008954:Models, Biological; D000459:Phaeophyceae / Q000254:growth & development*
keywords: bioelasticity; cell division; growth; morphogenesis; poroelasticity; seaweed