Patterned Disordered Cell Motion Ensures Vertebral Column Symmetry

Publication date: 24 July 2017
Source:Developmental Cell, Volume 42, Issue 2
Author(s): Dipjyoti Das, Veena Chatti, Thierry Emonet, Scott A. Holley
The biomechanics of posterior embryonic growth must be dynamically regulated to ensure bilateral symmetry of the spinal column. Throughout vertebrate trunk elongation, motile mesodermal progenitors undergo an order-to-disorder transition via an epithelial-to-mesenchymal transition and sort symmetrically into the left and right paraxial mesoderm. We combine theoretical modeling of cell migration in a tail-bud-like geometry with experimental data analysis to assess the importance of ordered and disordered cell motion. We find that increasing order in cell motion causes a phase transition from symmetric to asymmetric body elongation. In silico and in vivo, overly ordered cell motion converts normal anisotropic fluxes into stable vortices near the posterior tail bud, contributing to asymmetric cell sorting. Thus, disorder is a physical mechanism that ensures the bilateral symmetry of the spinal column. These physical properties of the tissue connect across scales such that patterned disorder at the cellular level leads to the emergence of organism-level order.

Graphical abstract

Teaser

Das et al. find that localized disorder in cell motion can function as a central component of a pattern-forming mechanism. This disorder is a physical mechanism that ensures the bilateral symmetry of the spinal column. Thus, patterned disorder at the cellular level leads to the emergence of organism-level order.


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