The Physical Basis of Coordinated Tissue Spreading in Zebrafish Gastrulation

Dev Cell. 2017 Feb 27;40(4):354-366.e4. doi: 10.1016/j.devcel.2017.01.010. Epub 2017 Feb 16.

Abstract

Embryo morphogenesis relies on highly coordinated movements of different tissues. However, remarkably little is known about how tissues coordinate their movements to shape the embryo. In zebrafish embryogenesis, coordinated tissue movements first become apparent during "doming," when the blastoderm begins to spread over the yolk sac, a process involving coordinated epithelial surface cell layer expansion and mesenchymal deep cell intercalations. Here, we find that active surface cell expansion represents the key process coordinating tissue movements during doming. By using a combination of theory and experiments, we show that epithelial surface cells not only trigger blastoderm expansion by reducing tissue surface tension, but also drive blastoderm thinning by inducing tissue contraction through radial deep cell intercalations. Thus, coordinated tissue expansion and thinning during doming relies on surface cells simultaneously controlling tissue surface tension and radial tissue contraction.

Keywords: active fluid description of tissue spreading; gastrulation; interfacial tension; radial cell intercalation; surface cell expansion; zebrafish.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biophysical Phenomena*
  • Blastoderm / cytology
  • Blastoderm / metabolism
  • Cell Communication
  • Cell Count
  • Cell Movement
  • Cell Proliferation
  • Computer Simulation
  • Embryo, Nonmammalian / cytology
  • Gastrulation*
  • Morphogenesis*
  • Stress, Physiological
  • Surface Tension
  • Zebrafish / embryology*
  • Zebrafish / physiology*