Raphael Clement

Contact

raphael.clement 'at' univ-amu.fr  /  website

Bio

Current work


Living systems display a fascinating diversity of spatial and temporal patterns. I’m interested in the biophysics of morphogenesis, the process by which such patterns and shapes emerge during embryonic development. 

Cell and tissue mechanics

 

During embryogenesis, living tissues constantly change their shape: they lengthen, round up, fold, form tubes, etc. Such tissue-scale changes require the coordinated action of cells in the tissue. I’m interested in the principles of cellular force generation, in the way these forces are coordinated and propagated to the surrounding tissue, and in how such forces are eventually converted into irreversible deformations to achieve morphogenesis. In that context, we have developed models and tools to study cellular mechanics in the fly embryo (optical tweezers, force inference).

Biophysics of wing expansion in insects (with Joel Marthelot and Simon Hadjaje)

 

During insect development, the future wings form during the larval and pupal stages. The fly wing disc (which prefigures the future wing), is actually a model system for the study of tissue growth. However, very little is known on the deployment of the adult wing. When the adult emerges from its pupal case, the wings are already formed, but they are still folded. The insect swallows air and increases its internal pressure, inflating its wings in a matter of minutes. We study the fluid-structure interaction that leads to the wing expansion. 

Dynamics of cell polarity in Trichoplax (with Andrea Pasini and Marvin Leria)

 

Trichoplax is said to be the simplest of all animals. No muscles, no nervous system, no digestive system, no respiratory system. It’s basically a flat bilayer of epithelial, ciliated cells. Yet it is strikingly dynamic, and can completely change its shape in a matter of minutes. How does Trichoplax achieve such plasticity without muscles? How does it adapt the polarity of its cilia to dynamically match its rapidly changing shape? 

Hierarchy and fate decision in neural tumors (with Cédric Maurange and Emma Legait)

 

Pediatric tumors often rely on a subset of so-called “cancer stem cells” that have the ability to sustain tumor growth. How a stable ratio of cancer stem cells is maintained in a tumor is largely unknown. We use tumors in the central nervous system of Drosophila to study this question, trying to understand how cell fate decisions are made so that tumor growth is sustained, and how a stable heterogeneity of cell types is maintained.