Migrating mesoderm cells self-organize into a dynamic meshwork structure during chick gastrulation.

Area of Science:

• Developmental Biology
• Cell Biology
• Biophysics

Background:

• Collective cell migration is vital for morphogenesis and disease.
• Mechanisms of epithelial cell migration are understood, but mesenchymal cell coordination remains unclear.
• Mesenchymal cells extensively migrate during embryonic development.

Purpose of the Study:

• To investigate the collective migration mechanisms of mesenchymal cells during chick gastrulation.
• To characterize the novel collective migration patterns of these cells.
• To identify key factors regulating mesenchymal cell meshwork formation.

Main Methods:

• Live imaging of chick gastrulation.
• Quantitative analysis, including topological data analysis (TDA).
• Agent-based theoretical modeling.

Main Results:

• Mesenchymal cells form a meshwork structure during collective migration away from the primitive streak.
• Overexpression of mutant N-cadherin reduced tissue progression speed and directionality, without affecting individual cell speed.
• Agent-based modeling identified cell elongation, adhesion, and density as key for meshwork formation.

Conclusions:

• Mesenchymal cells exhibit a novel form of collective migration forming a supracellular meshwork.
• Cell-cell adhesion, mediated by N-cadherin, plays a role in coordinating collective mesenchymal cell movement.
• Cell elongation, adhesion, and density are critical parameters for generating this meshwork structure in loosely connected cell populations.