Over the past decade, our knowledge and understanding of molecular regulatory networks involved in plant development has increased a lot. A key challenge now is to understand how these signals, which arise at cellular scale, are physically translated into growth at organ scale and how these shape changes feed back into molecular regulation systems. To address this question, we developed a computational framework to model the mechanics of 3D growing tissues with cellular resolution. Within this framework, gene expression patterns are expressed in terms of in-homogenous mechanical properties and control a differential growth equation. Our computational system makes it possible to integrate this equation in both space and time over the growing multicellular structure in close to interactive time. We demonstrate the interest of such a framework to study morphogenesis by constructing a model of flower development, showing how regulation of regional identities can, by dynamically modulating the mechanical properties of cells, lead to realistic shape development.

This is a joint work with Frédéric Boudon, Jérôme Chopard, Benjamin Gilles, Olivier Hamant, Arezki Boudaoud, Jan Traas and Christophe Godin