Reference : PhD Daniel Riveline
Transformations of tissue shapes have been the increasing focus of interest for physicists, biologists, and chemists. Between mechanics and signaling pathways, these phenomena require interdisciplinary culture to understand the physical formalisms and the associated biological approaches.
The PhD topic proposes to probe the coupling between chemical signals and mechanical effects. It is possible to measure the spatial and temporal signature of small GTPases involved in signaling; and for mechanics, cell shapes, acto-myosin distributions and constraints applied by cells can be measured. In addition, other features can be tested, for example comparisons between these tissue dynamics and passive and active foams which share similar rules of organisation.
Experiments will be performed by measuring signaling and mechanics within the same sets of acquisitions, in order to identify the respective contributions of both aspects of morphogenesis on epithelial layers in 2D and in 3D, as well as on organoids.
If results are conclusive, experiments will be extended to other cellular systems from model organisms. At IGBMC, we have access to cells from mice, from Zebrafish and C. elegans, and the extraction of epithelial cells and the local outstanding expertise will allow to reproduce these experiments for a variety of cellular systems together with established international collaborations. Finally, tight links with a group of theorist will be further strengthened to integrate data into a mesoscopic model for tissue dynamics. The classical article of Turing on morphogenesis proposes morphogen concept and its consequences in terms of chemical patterns, but mechanics is not taken into account.
This PhD will allow to explore mechanical aspects of living matter, and the expected coupling with signaling pathways. It will imply cell biology, microfabrication, theory, developmental biology. It could reveal new paradigms for explaining morphogenetic events in developmental biology.
Date limite de candidature : 1 novembre 2018