Tissue Packing and Unpacking with Deformable Polygons

by Dr John D. Treado (MPI PKS Dresden)

Friday 30 May 2025, 14:30 → 15:30 Europe/Rome

1/2-07 - Sala 207 (Dipartimento di Fisica e Astronomia - Edificio Paolotti)

Biological tissues are determined by the collective behaviors of cells. While cells play an important role in defining the chemical and genetic landscape of a tissue, they also define its mechanical landscape. As cells interact and have well defined mechanical characteristics, cells play a similar role to passive particles in complex soft materials. However, as autonomous agents, cells can collectively tune the material properties of their tissues in ways unseen in passive systems. In my talk, I will introduce the Deformable Polygon model as a tool to understand how collective cellular behavior leads to complex tissue mechanics. First, I will present work on jamming in athermal packings of Deformable Polygons, which display exotic mechanical properties such as hypostatic coordination and non-linear stability. I will then turn to a biological application of this model, where we use Deformable Polygons to study the morphogenesis of plant leaves. Plant leaves require large pore spaces to facilitate airflow for respiration, but most undeveloped plant tissues start their life cycle almost perfectly packed. I will show how we have used Deformable Polygons to understand how plant cells can tune the porosity of their tissue by choosing where and when to grow. I will conclude with an outlook for future directions of this model, in particular the addition of active hydraulic forces to further understand the morphogenesis and behavior of luminal tissues and active epithelia.