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Séminaires MSC
"Matière et Systèmes Complexes"

                      

Lundi 1er octobre 2007 à 11h30
Bâtiment Condorcet, 4ème étage, salle 454 A.


Yohanns Bellaiche (Institut Curie)

et Sébastien Courty (LKB, ENS, Paris


QuantifIcation of 3D cellular pattern dynamics and Its application to tissue morphogenesis

Understanding how biological tissues grow, acquire and maintain their global shape requires the analysis of cell polarization mechanisms at the single cell level but also to decipher how the general organization and dynamics of biological tissue are achieved and maintained.

While the mechanisms of polarization at the single cell level are starting to be established, our understanding of how cell polarization is translated into tissues growth, morphogenesis and homeostasis is minimal. Indeed, during epithelial tissue morphogenesis and homeostasis, tissues show complex dynamics governed by different cellular mechanisms such as topological cell rearrangements, cell divisions and cell growth.

Using a general multiscale mathematical approach that allow the description and quantification of 3D cellular pattern such as foams, cells, grains in polycrystal, we can now link the behavior of single cells to the development of the epithelial tissue taking into account cell rearrangements, cell division, cell growth and cell apoptosis. Doing so we were able to demonstrate that cell growth and cell division orientation are finely controlled during tissue morphogenesis and that such regulation is essential to allow epithelial tissue morphogenesis. Finally, our approach provides a general and novel framework to understand how cell growth is translated into tissue growth, morphogenesis and homeostasis.