René Marc Mège, Centre National de la Recherche Scientifique (CNRS)

Seminar Room 0.125, MPZPM, Kussmaulallee 2, 91054 Erlangen

Location Details

Abstract
Cells as active systems generate and adapt internal stresses and traction forces in response to these mechanical cues. The underlying mechanisms rely on actomyosin-generated forces, as well as cell–matrix and cell–cell adhesions mechanotransduction and -sensing. However, cell contractility fails to explain some tissue behaviors highlighting alternative mechanisms, such as active ion and water transport through which cells can generate stresses. Despite the existence of fluid and osmolyte gradients in organs and tissues, including epithelia, the role of active ionic transport and water flow has been largely overlooked to understand epithelial cell behavior. 
We developed a model of microsized hydrogel spheres coated by epithelila monolayer which allows to decipher the interplay between these cellular activities and tissue mechanics, which allowed us to demonstrate the critical role of fluid transport in generating mechanical forces within epithelial tissues. Supported by a theoretical mechanohydraulic model, a mechanistic framework for understanding the intricate interplay between cellular processes and tissue mechanics was established. These results challenge traditional views of epithelial tissue mechanics, emphasizing the pivotal influence of osmotic and mechanical pressures in shaping tissues.

Biography

Dr. René Marc Mège is CNRS (Centre National de la Recherche Scientifique) Research Director. He heads the “Cell Adhesion & Mechanics” lab at the Institut Jacques Monod, Université Paris Cité.
RMM was trained as a Biochemist in the University of Bordeaux (France), obtained a PhD in Enzymology and Biotechnology at the University of Technology of Compiègne (France). He then moved to cell and developmental biology and spend three years at the Rockefeller University (New York, USA) in the lab of the Nobel Prize Gerald M Edelman where he specialized in cell-cell interaction and adhesion. He was hired at CNRS in 1991, became group leader in 1996, and Research Director in 2005. He has been heading the Neural Cell Adhesion and Migration” team at INSERM-Institut du Fer à Moulin, Paris until 2012. He has been teaching cell biology and biochemistry as Associate Professor at Ecole Polytechnique (Palaiseau) from 2003 to 2017. He is head of the national infrastructure France BioImaging Since 2024.