Active dynamics of tissue shear flow

Marko Popović (1) , Amitabha Nandi (2, 1) , Matthias Merkel (3, 1) , Raphael Etournay (4, 5) , Suzanne Eaton (5) , Frank Jülicher (1) , Guillaume Salbreux (6, 1)

1 MPI-PKS - Max Planck Institute for the Physics of Complex Systems
2 IIT Bombay - Indian Institute of Technology Bombay
3 Syracuse University
4 IP - Institut Pasteur [Paris]
5 MPI-CBG - Max Planck Institute of Molecular Cell Biology and Genetics
6 The Francis Crick Institute [London]

We present a hydrodynamic theory to describe shear flows in developing epithelial tissues. We introduce hydrodynamic fields corresponding to state properties of constituent cells as well as a contribution to overall tissue shear flow due to rearrangements in cell network topology. We then construct a generic linear constitutive equation for the shear rate due to topological rearrangements and we investigate a novel rheological behaviour resulting from memory effects in the tissue. We identify two distinct active cellular processes: generation of active stress in the tissue, and actively driven topological rearrangements. We find that these two active processes can produce distinct cellular and tissue shape changes, depending on boundary conditions applied on the tissue. Our findings have consequences for the understanding of tissue morphogenesis during development.

Keywords: biological physics; tissue mechanics; rheology; hydrodynamics; active matter

Domains: Cellular Biology; Soft Condensed Matter [cond-mat.soft]; Mechanics [physics]; Fluid mechanics [physics.class-ph]; Development Biology; Quantitative Methods [q-bio.QM]

Marko Popović, Amitabha Nandi, Matthias Merkel, Raphael Etournay, Suzanne Eaton, et al.. Active dynamics of tissue shear flow. New Journal of Physics, 2017, 19 (3), pp.033006. ⟨10.1088/1367-2630/aa5756⟩. ⟨pasteur-01545826⟩