Morphogenetic degeneracies in the actomyosin cortex
Abstract
One of the great challenges in biology is to understand the mechanisms by which morphogenetic processes arise from molecular activities. We investigated this problem in the context of actomyosin-based cortical flow in C. elegans zygotes, where large-scale flows emerge from the collective action of actomyosin filaments and actin binding proteins (ABPs). Large-scale flow dynamics can be captured by active gel theory by considering force balances and conservation laws in the actomyosin cortex. However, which molecular activities contribute to flow dynamics and large-scale physical properties such as viscosity and active torque is largely unknown. By performing a candidate RNAi screen of ABPs and actomyosin regulators we demonstrate that perturbing distinct molecular processes can lead to similar flow phenotypes. This is indicative for a 'morphogenetic degeneracy' where multiple molecular processes contribute to the same large-scale physical property. We speculate that morphogenetic degeneracies contribute to the robustness of bulk biological matter in development.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
Deutsche Forschungsgemeinschaft (SPP 1782)
- Stephan W Grill
ITN (641639)
- Stephan W Grill
Human Frontier Science Program (LT000078/2016)
- Sundar Ram Naganathan
Human Frontier Science Program (LT000871/2014)
- Sebastian Fürthauer
European Research Council (281903)
- Stephan W Grill
ITN (281903)
- Stephan W Grill
Human Frontier Science Program (RGP0023/2014)
- Stephan W Grill
Max-Planck-Gesellschaft (Open-access funding)
- Sundar Ram Naganathan
Deutsche Forschungsgemeinschaft (GSC 97)
- Stephan W Grill
Deutsche Forschungsgemeinschaft (GR 3271/2)
- Stephan W Grill
Deutsche Forschungsgemeinschaft (GR 3271/3)
- Stephan W Grill
Deutsche Forschungsgemeinschaft (GR 3271/4)
- Stephan W Grill
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Naganathan 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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