Fgf4 maintains Hes7 levels critical for normal somite segmentation clock function
Abstract
During vertebrate development, the presomitic mesoderm (PSM) periodically segments into somites, which will form the segmented vertebral column and associated muscle, connective tissue, and dermis. The periodicity of somitogenesis is regulated by a segmentation clock of oscillating Notch activity. Here, we examined mouse mutants lacking only Fgf4 or Fgf8, which we previously demonstrated act redundantly to prevent PSM differentiation. Fgf8 is not required for somitogenesis, but Fgf4 mutants display a range of vertebral defects. We analyzed Fgf4 mutants by quantifying mRNAs fluorescently labeled by hybridization chain reaction within Imaris-based volumetric tissue subsets. These data indicate that FGF4 maintains Hes7 levels and normal oscillatory patterns. To support our hypothesis that FGF4 regulates somitogenesis through Hes7, we demonstrate genetic synergy between Hes7 and Fgf4, but not with Fgf8. Our data indicate that Fgf4 is potentially important in a spectrum of human Segmentation Defects of the Vertebrae caused by defective Notch oscillations.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files.
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Author details
Funding
National Cancer Institute (ZIA BC010338-19)
- Mark Lewandoski
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Marianne E Bronner, California Institute of Technology, United States
Ethics
Animal experimentation: Animal experimentation: All experimental procedures followed the National Institutes of Health Guidelines for animal care and use, and were approved by the NCI-Frederick Animal Care and Use Committee. (Animal Study Protocol 17-069)
Version history
- Received: January 30, 2020
- Accepted: November 18, 2020
- Accepted Manuscript published: November 19, 2020 (version 1)
- Version of Record published: December 4, 2020 (version 2)
- Version of Record updated: January 18, 2021 (version 3)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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