Morphogenesis of the primitive gut tube is generated by Rho/ROCK/myosin II-mediated endoderm rearrangements

Dev Dyn. 2009 Dec;238(12):3111-25. doi: 10.1002/dvdy.22157.


During digestive organogenesis, the primitive gut tube (PGT) undergoes dramatic elongation and forms a lumen lined by a single-layer of epithelium. In Xenopus, endoderm cells in the core of the PGT rearrange during gut elongation, but the morphogenetic mechanisms controlling their reorganization are undetermined. Here, we define the dynamic changes in endoderm cell shape, polarity, and tissue architecture that underlie Xenopus gut morphogenesis. Gut endoderm cells intercalate radially, between their anterior and posterior neighbors, transforming the nearly solid endoderm core into a single layer of epithelium while concomitantly eliciting "radially convergent" extension within the gut walls. Inhibition of Rho/ROCK/Myosin II activity prevents endoderm rearrangements and consequently perturbs both gut elongation and digestive epithelial morphogenesis. Our results suggest that the cellular and molecular events driving tissue elongation in the PGT are mechanistically analogous to those that function during gastrulation, but occur within a novel cylindrical geometry to generate an epithelial-lined tube.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Body Patterning / genetics
  • Cell Polarity / genetics
  • Cell Shape / genetics
  • Embryo, Nonmammalian
  • Endoderm / cytology
  • Endoderm / embryology*
  • Endoderm / metabolism
  • Gastrointestinal Diseases / congenital
  • Gastrointestinal Diseases / embryology
  • Gastrointestinal Tract / abnormalities
  • Gastrointestinal Tract / embryology
  • Gastrula / embryology*
  • Gastrula / metabolism
  • Models, Biological
  • Morphogenesis / genetics*
  • Nonmuscle Myosin Type IIB / genetics
  • Nonmuscle Myosin Type IIB / metabolism
  • Nonmuscle Myosin Type IIB / physiology*
  • Signal Transduction / genetics
  • Xenopus / embryology
  • Xenopus / genetics
  • Xenopus / metabolism
  • rho-Associated Kinases / genetics
  • rho-Associated Kinases / metabolism
  • rho-Associated Kinases / physiology*
  • rhoA GTP-Binding Protein / genetics
  • rhoA GTP-Binding Protein / metabolism
  • rhoA GTP-Binding Protein / physiology*


  • rho-Associated Kinases
  • Nonmuscle Myosin Type IIB
  • rhoA GTP-Binding Protein