title: Controlling contractile instabilities in the actomyosin cortex.
abstract: The actomyosin cell cortex is an active contractile material for driving cell- and tissue morphogenesis. The cortex has a tendency to form a pattern of myosin foci, which is a signature of potentially unstable behavior. How a system that is prone to such instabilities can rveliably drive morphogenesis remains an outstanding question. Here, we report that in theCaenorhabditis eleganszygote, feedback between active RhoA and myosin induces a contractile instability in the cortex. We discover that an independent RhoA pacemaking oscillator controls this instability, generating a pulsatory pattern of myosin foci and preventing the collapse of cortical material into a few dynamic contracting regions. Our work reveals how contractile instabilities that are natural to occur in mechanically active media can be biochemically controlled to robustly drive morphogenetic events.
authors.affiliation: Biotechnology Center, Technical University Dresden, Dresden, Germany.|Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.|Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
authors.forename: Masatoshi
authors.identifier: 0000-0001-6502-7907
authors.initials: M
authors.lastname: Nishikawa
authors.affiliation: Biotechnology Center, Technical University Dresden, Dresden, Germany.|Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.|Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
authors.forename: Sundar Ram
authors.initials: SR
authors.lastname: Naganathan
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.
authors.forename: Frank
authors.identifier: 0000-0003-4731-9185
authors.initials: F
authors.lastname: Jülicher
authors.affiliation: Biotechnology Center, Technical University Dresden, Dresden, Germany.|Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.|Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
authors.forename: Stephan W
authors.identifier: 0000-0002-2290-5826
authors.initials: SW
authors.lastname: Grill
mesh_terms: D000205:Actomyosin / Q000378:metabolism*; D000818:Animals; D017173:Caenorhabditis elegans / Q000502:physiology*; D025461:Feedback, Physiological; D009024:Morphogenesis; D015053:Zygote / Q000502:physiology*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism*
chemical_list: D000205:Actomyosin; D020742:rhoA GTP-Binding Protein
keywords: C. elegans; active gel; actomyosin cortex; biophysics; contractile instability; pattern formation; structural biology