Emmanuel Derivery

Asymmetric cell division is the process by which one cell divides into two daughter cells that have different fates. Asymmetric division is the hallmark of stem cells, in which one daughter cell specialises to perform a specific function in the organism, while the other becomes another stem cell that keeps the ability to divide. We are interested in understanding how cell fate determinants segregate asymmetrically during asymmetric division. In particular, we focus on finding the molecular and physical mechanisms by which polarity cues are “written” onto the microtubule cytoskeleton during asymmetric division and how, in turn, these polarity signals are “read” by molecular motors to carry endosomes containing fate determinants into only one daughter cell. Our approach is highly pluridisciplinary, from reconstituted cytoskeleton systems in vitro, high-end quantitative imaging of trafficking in vivo during development, to analysis of morphological phenotypes in adult flies, relying on theoretical physics to bridge these different scales. We also develop novel imaging and bioengineering tools. For instance, we have developed techniques to induce polarity in unpolarised cells, using micropatterning and protein design. This induced polarity allows us to explore the molecular mechanisms underpinning symmetry breaking of the cytoskeleton. Our long term vision is capitalize on this work in Drosophila to restore asymmetric cell fate in situations where it has been lost in mammalian stem cells, such as during ageing or tumorigenesis.