Center for Plant Molecular Biology

Gabriella Mosca lab

Biomechanical Modeling of Morphogenesis (BM2)

Research

The Biomechanical Modeling of Morphogenesis (BM2) Lab is  interested in understanding morphogenesis, biomechanics and their interaction in living systems, mostly plants.

 

Examples of morphogenetic processes
The problem of morphogenesis can be studied at different levels, such as: (i) growth of a whole organ and how its architecture is organized, (ii) marginal patterning of a leaf, (iii) differentiation at the cellular level

We use and develop computational tools (MorphoMechanX) which enable us to test in-silico explanatory and predictive scenarios connected to morphogenesis and bio-mechanics. In particular, we use Finite Element Methods based simulations to model cell growth and the mechanical forces at play in multi-cellular tissue context: in this way it is possible to study in a physically realistic environment the interactions between (i) growth specifying agents (unspecifically termed morphogens), (ii) cell wall mechanical properties (including their dynamical changes), (iii) the evolving cell shapes and geometries.

Indentation simulation on a portion of Arabidopsis meristem (adapted from Long et al., Curr Biol. 2020)

These methods, combined with experimental data obtained through a variety of techniques (i.e. confocal microscopy, AFM, CFM, extensometer, osmotic treatmens and gene editing) by partner labs, allow us to tackle a variety of problems in the plant (but occasionally also animal) kingdom. Our goal is to gather, through a bottom up approach, a holistic understanding of how organisms coordinate their tissue/organ growth and in particular what is the role played by mechanics.

 

Pattern of stress intensity (heatmap) and stretch direction (white lines tensile, red lines compressive) in a puzzle cell within a tissue context. Adapted from Sapala et al., eLife 2018

Especially in plants, when trying to understand morphogenesis, mechanics should be factored in. In fact: 

(i) the cell wall withstands high forces under the action of turgor pressure;
(ii) the cell wall is made of a complex structure conferring to it non-homogeneous and anisotropic mechanical properties, which can also vary dynamically;
(iii) growth occurs symplastically, with cells not able to freely slide one w.r.t. each other, so that residual stresses are introduces to accommodate different rates and directions of growth;
(iv) there is good evidence  that growth in plant cells is affected by their state of tension and compression.

For these reasons, a deep understanding of plant morphogenesis requires to include bio-mechanics and the in-silico approach is a valuable tool to disentangle virtually the effect of the different elements (i.e. signaling, cell intrinsic mechanics, cell shape, tissue conflict effects..)

Current Projects

 

More details coming soon!