Using mechanics in the modelling of meristem morphogenesis

Shoot apical meristems are small groups of rapidly dividing, undifferentiated cells, which generate all aerial parts of the plants. Recently, spectacul ar advances in molecular biology and genetics have provided a wealth of information on meristem functioning. However, the amount of available information is now such, that an integrated view is no longer possible. As a result, researchers have been led to develop computational models in the form of virtual meristems to analyse this complexity in silico and to test different hypotheses. Only very recently three such models have been described [10, 1, 5]. All three are able to integrate various cell-based processes and show different emerging behaviours (e.g. meristem maintenance, phyllotaxis). This pioneering work has demonstrated that the in silico analysis of plant development can be an extremely useful complement to classical experimentation. Previous models have focused their interrogations on physiological processes in the meristem for a given, predefined, tissue shape. However, in nature, the shape itself is the result of a continuous feedback loop between physiological information and growth. As suggested by [4, 2], the mechanical components of the cells could provide such a link. In this work, we consider the problem of integrating such a feedback loop in meristem development.