PHD2019-02

Conditions for self-organized oriented deformation of biological tissue

Host laboratory and collaborators

Matthias Merkel - CPT - matthias.merkel@univ-amu.fr

Scientific background

During their development from egg cell to adult, multi-cellular organisms acquire intricate shapes and patterns robustly and in a completely self-organized manner. One of the fundamental processes allowing this is the oriented deformation of involved tissues. From a physical perspective, oriented tissue deformation is possible because living tissues are active materials, i.e. materials that locally transform chemical energy into mechanical energy. However, general physical theories for active materials predict instabilities in oriented deformation processes. Thus, one key question relevant for the development of any animal is: How are such instabilities prevented (or even harnessed) in biological tissues?

PhD Objectives

The goal is to formulate general necessary and/or sufficient criteria under which self-organized tissue deformation is possible. One part of this will be to study how active tissue deformation interacts with gradients of proteins called morphogens. Another part will study in how far previous results on active oriented materials can be applied to biological tissues. Theoretical and computational work will be combined with close collaborations with experimentalists.

Proposed approach

To study these questions both in 2D and 3D, the analytical and numerical study of continuum models for active oriented materials will be combined with simulations of cell-based tissue models. For the latter, the focus will be on vertex models, which describe the biological tissues as networks of polygons (2D) or polyhedra (3D).

PhD student’s expected profile

I am looking for a curious and highly motivated student with a master degree in physics or mathematics.

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