title: Decrease in Cell Volume Generates Contractile Forces Driving Dorsal Closure.
abstract: Biological tissues must generate forces to shape organs and achieve proper development. Such forces often result from the contraction of an apical acto-myosin meshwork. Here we describe an alternative mechanism for tissue contraction, based on individual cell volume change. We show that during Drosophila dorsal closure (DC), a wound healing-related process, the contraction of the amnioserosa (AS) is associated with a major reduction of the volume of its cells, triggered by caspase activation at the onset of the apoptotic program of AS cells. Cell volume decrease results in a contractile force that promotes tissue shrinkage. Estimating mechanical tensions with laser dissection and using 3D biophysical modeling, we show that the cell volume decrease acts together with the contraction of the actin cable surrounding the tissue to govern DC kinetics. Our study identifies a mechanism by which tissues generate forces and movements by modulating individual cell volume during development.
authors.affiliation: Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona 08003, Spain; Universitat Pompeu Fabra, Barcelona 08003, Spain.
authors.forename: Laure
authors.initials: L
authors.lastname: Saias
authors.affiliation: Universitat Pompeu Fabra, Barcelona 08003, Spain; EMBL-CRG Systems Biology Unit, Centre for Genomic Regulation, Barcelona 08003, Spain.
authors.forename: Jim
authors.initials: J
authors.lastname: Swoger
authors.affiliation: Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona 08003, Spain; Universitat Pompeu Fabra, Barcelona 08003, Spain.
authors.forename: Arturo
authors.initials: A
authors.lastname: D'Angelo
authors.affiliation: Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona 08003, Spain; Universitat Pompeu Fabra, Barcelona 08003, Spain.
authors.forename: Peran
authors.initials: P
authors.lastname: Hayes
authors.affiliation: Advanced Digital Microscopy, Institute for Research in Biomedicine, Barcelona 08028, Spain.
authors.forename: Julien
authors.initials: J
authors.lastname: Colombelli
authors.affiliation: Universitat Pompeu Fabra, Barcelona 08003, Spain; EMBL-CRG Systems Biology Unit, Centre for Genomic Regulation, Barcelona 08003, Spain; Institució Catalana de Recerca I Estudis Avançats, Barcelona 08010, Spain.
authors.forename: James
authors.initials: J
authors.lastname: Sharpe
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany. Electronic address: salbreux@pks.mpg.de.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Salbreux
authors.affiliation: Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona 08003, Spain; Universitat Pompeu Fabra, Barcelona 08003, Spain. Electronic address: jerome.solon@crg.es.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Solon
mesh_terms: D008841:Actin Cytoskeleton / Q000502:physiology*; D000818:Animals; D001696:Biomechanical Phenomena; D020169:Caspases / Q000378:metabolism; D048429:Cell Size; D004330:Drosophila / Q000196:embryology* / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D040542:Mechanotransduction, Cellular; D009024:Morphogenesis / Q000502:physiology*; D009218:Myosins / Q000378:metabolism; D010766:Phosphorylation; D012704:Serous Membrane / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D029721:Drosophila Proteins; D020169:Caspases; D009218:Myosins