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Broad mesodermal and endodermal deletion of Nodal at postgastrulation stages results solely in left/right axial

Amit Kumar1, Margaret Lualdi, Mark Lewandoski

  • 1Laboratory of Protein Dynamics and Signaling, National Cancer Institute, NCI-Frederick, National Institutes of Health, Frederick, Maryland 21702, USA.

Developmental Dynamics : an Official Publication of the American Association of Anatomists
|September 6, 2008
PubMed

Insights

Nodal signaling is essential for left/right (LR) axis development in vertebrates. Conditional mutagenesis revealed Nodal

Area of Science:

  • Developmental Biology
  • Genetics
  • Molecular Biology

Background:

  • Nodal signaling is crucial for vertebrate embryonic development, particularly left/right (LR) axis formation.
  • Understanding Nodal's specific roles post-gastrulation requires precise genetic tools.

Purpose of the Study:

  • To investigate the function of Nodal signaling specifically in the post-gastrulation embryo.
  • To determine if Nodal has essential roles in mesodermal and endodermal patterning beyond LR axis development.

Main Methods:

  • Generation of a floxed Nodal allele with wild-type function.
  • Utilized the T-Cre conditional mutagenesis system to delete Nodal in mesodermal and endodermal lineages.
  • Analysis of embryonic development following targeted Nodal deletion.

Main Results:

  • Complete deletion of Nodal in the T-Cre expression domain abrogated normal transient expression in the lateral plate mesoderm.
  • Severe left/right developmental defects were observed in mutant embryos.
  • No other developmental abnormalities were detected in the affected tissues.

Conclusions:

  • Nodal signaling is indispensable for establishing left/right asymmetry in vertebrate development.
  • Nodal signaling does not appear to have essential functions in the broader patterning of mesodermal and endodermal tissues during post-gastrulation development.

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