Recent Publication — Journal of Physics: Condensed Matter, 28(41)

Embryo as an active granular fluid: stress-coordinated cellular constriction chains

Guo-Jie Jason Gao, Michael C Holcomb, Jeffrey H Thomas, and Jerzy Blawzdziewicz

ABSTRACT

Mechanical stress plays an intricate role in gene expression in individual cells and sculpting of developing tissues. However, systematic methods of studying how mechanical stress and feedback help to harmonize cellular activities within a tissue have yet to be developed. Motivated by our observation of the cellular constriction chains (CCCs) during the initial phase of ventral furrow formation in the Drosophila melanogaster embryo, we propose an active granular fluid (AGF) model that provides valuable insights into cellular coordination in the apical constriction process. In our model, cells are treated as circular particles connected by a predefined force network, and they undergo a random constriction process in which the particle constriction probability P is a function of the stress exerted on the particle by its neighbors. We find that when P favors tensile stress, constricted particles tend to form chain-like structures. In contrast, constricted particles tend to form compact clusters when P favors compression. A remarkable similarity of constricted-particle chains and CCCs observed in vivo provides indirect evidence that tensile-stress feedback coordinates the apical constriction activity. Our particle-based AGF model will be useful in analyzing mechanical feedback effects in a wide variety of morphogenesis and organogenesis phenomena.

Read the article on IOP Science or Arxiv.org (full text).

Image of a glass sphere with a scenic mountain view behind it. The sphere contains an upside-down reflection of the landscape.

Teaching Philosophy

Adaptability and student-centered mentorship inform my teaching philosophy.

Image of a fruit fly (Drosophila melanogaster) atop a plant. Photo by Géry Parent

Research

I use dynamic system modeling to represent embryonic tissues as a mechanically active media.