Microphase separation of living cells
Self-organization of cells is central to biological systems and understanding the underlying mechanisms is a long-standing quest. Our recent experiments on the model organism
Dictyostelium discoideum show that those motile cells can spontaneously self-assemble into
compact aggregates with a characteristic size of 100 μm. The phenomenon is in fact akin to a microphase separation [1].
Microphase separation is an equilibrium phenomenon where the
formation of domains is induced by competing interactions, usually a short-range attraction opposed by a long-range repulsion. Over the last 40 years, the phenomenon has been recognized in several physical systems, from magnetic films and superconductors to liquid crystals, colloids and copolymers. However, it has never been observed with living cells. The recent experimental results thus raise a host of questions.
The goal of the internship is to explore the microphase-separation of cells using
numerical simulations. Our model describes each cell individually and account only for the essential ingredients: adhesion between cells, consumption of oxygen and motion toward oxygen-rich regions. The simulations so far provide an understanding of the domain size but many facets of the microphase separation deserve to be explored, from the various morphologies possible to the
dynamic properties of the very mobile domains.
The student will exploit and expand a simulation code that is already functional. A taste for numerical techniques is desirable. No background in biology is required. The work lies at the interface of
statistical physics, biophysics and active matter.
Continuation as a
PhD is possible.
[1] Microphase separation of living cells. Carrère et al. In revision for
Nature Communications.
[preprint]
Key-words: biophysics, numerical simulations, statistical physics, soft and active matter.
Contact:
François Detcheverry
francois.detcheverry@univ-lyon1.fr Team
Liquides et Interfaces,
Jean-Paul Rieu
jean-paul.rieu@univ-lyon1.fr Team
Biophysics,
Institut Lumière Matière (Lyon)