Generating active T1 transitions through mechanochemical feedback

eLife, vol. 12

Abstract

Convergence-extension in embryos is controlled by chemical and mechanical signalling. A key cellular process is the exchange of neighbours via T1 transitions. We propose and analyse a model with positive feedback between recruitment of myosin motors and mechanical tension in cell junctions. The model produces active T1 events, which act to elongate the tissue perpendicular to the main direction of tissue stress. Using an idealised tissue patch comprising several active cells embedded in a matrix of passive hexagonal cells, we identified an optimal range of mechanical stresses to trigger an active T1 event. We show that directed stresses also generate tension chains in a realistic patch made entirely of active cells of random shapes and leads to convergence-extension over a range of parameters. Our findings show that active intercalations can generate stress that activates T1 events in neighbouring cells, resulting in tension-dependent tissue reorganisation, in qualitative agreement with experiments on gastrulation in chick embryos.

Authors 5

1. Rastko Sknepnek

   University of Dundee

   Affiliation as printed

   School of Life Sciences, University of Dundee

   School of Science and Engineering, University of Dundee

   School of Life Sciences, University of Dundee, Dundee, United Kingdom;

   School of Science and Engineering, University of Dundee, Dundee, United Kingdom;

2. Ilyas Djafer-Cherif

   University of Bristol

   Affiliation as printed

   School of Mathematics, University of Bristol

   School of Mathematics, University of Bristol, Bristol, United Kingdom;

3. Manli Chuai

   University of Dundee

   Affiliation as printed

   School of Life Sciences, University of Dundee

   School of Life Sciences, University of Dundee, Dundee, United Kingdom;

4. Cornelis Jan Weijer

   University of Dundee

   Affiliation as printed

   School of Life Sciences, University of Dundee

   School of Life Sciences, University of Dundee, Dundee, United Kingdom;

5. Silke Henkes Aachen

   Leiden University · University of Bristol

   Affiliation as printed

   Leiden Institute of Physics, Leiden University

   School of Mathematics, University of Bristol

   Leiden Institute of Physics, Leiden University, Leiden, Netherlands

   School of Mathematics, University of Bristol, Bristol, United Kingdom;