Generating active T1 transitions through mechanochemical feedback
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 idealized 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.
Data availability
The current manuscript is primarily a computational study, so no data have been generated for this manuscript. Modelling code is publically (GNU public license v 2.0) available on GitHub at: https://github.com/sknepneklab/ActiveJunctionModelThe experimental data presented in Figure 8 and Figure 8 - figure supplement 1 has been generated as described in the methods section.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/N009789/1)
- Rastko Sknepnek
- Manli Chuai
- Cornelis Weijer
Biotechnology and Biological Sciences Research Council (BB/N009150/1-2)
- Ilyas Djafer-Cherif
- Silke Henkes
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Sknepnek et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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