title: Nature and anisotropy of cortical forces orienting Drosophila tissue morphogenesis.
abstract: The morphogenesis of developing embryos and organs relies on the ability of cells to remodel their contacts with neighbouring cells. Using quantitative modelling and laser nano-dissection, we probed the mechanics of a morphogenetic process, the elongation of Drosophila melanogaster embryos, which results from polarized cell neighbour exchanges. We show that anisotropy of cortical tension at apical cell junctions is sufficient to drive tissue elongation. We estimated its value through comparisons between in silico and in vivo data using various tissue descriptors. Nano-dissection of the actomyosin network indicates that tension is anisotropically distributed and depends on myosin II accumulation. Junction relaxation after nano-dissection also suggests that cortical elastic forces are dominant in this process. Interestingly, fluctuations in vertex position (points where three or more cells meet) facilitate neighbour exchanges. We delineate the contribution of subcellular tensile activity polarizing junction remodelling, and the permissive role of vertex fluctuations during tissue elongation.
authors.affiliation: Institut Fresnel, Université Aix-Marseille III, CNRS, Ecole Centrale Marseille, UMR 6133, Domaine Universitaire de St Jérôme, 13397 Marseille cedex 20, France.
authors.forename: Matteo
authors.initials: M
authors.lastname: Rauzi
authors.forename: Pascale
authors.initials: P
authors.lastname: Verant
authors.forename: Thomas
authors.initials: T
authors.lastname: Lecuit
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Lenne
mesh_terms: D000818:Animals; D016880:Anisotropy; D019295:Computational Biology; D004210:Dissection; D004331:Drosophila melanogaster / Q000196:embryology* / Q000502:physiology*; D004548:Elasticity; D004625:Embryo, Nonmammalian / Q000502:physiology; D007834:Lasers; D008954:Models, Biological; D009024:Morphogenesis; D009218:Myosins / Q000378:metabolism
chemical_list: D009218:Myosins