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Application of Impermeable Barriers Combined with Candidate Factor Soaked Beads to Study Inductive Signals in the Chick
Published on: November 17, 2016
Shh pathway activation is present and required within the vertebrate limb bud apical ectodermal ridge for normal
Cortney M Bouldin1, Amel Gritli-Linde, Sohyun Ahn
1Department of Molecular Genetics and Microbiology, The Genetics Institute, University of Florida, Gainesville, FL 32610, USA.
Summary
The Hedgehog (Hh) signaling pathway is active in the developing limb bud ectoderm, contrary to previous beliefs. This pathway is essential for normal limb patterning and digit development in the autopod.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- Sonic Hedgehog (Shh) expression in limb bud mesenchyme regulates limb development via the Hedgehog (Hh) signaling pathway.
- Previous studies indicated Hh signaling is absent in limb bud ectoderm due to a lack of pathway components and targets.
Purpose of the Study:
- To investigate the presence and role of Hh signaling in the developing limb bud ectoderm.
- To determine if Hh signaling in the apical ectodermal ridge (AER) is necessary for limb patterning.
Main Methods:
- Utilized immunohistochemistry and target detection methods to identify Shh protein and Hh signaling targets in limb bud ectoderm.
- Genetically removed Smo, a key Hh pathway component, from the AER to assess its impact on limb development.
Main Results:
- Confirmed the presence of Shh protein and Hh signaling targets within the limb bud ectoderm, including the AER.
- Removal of Smo from the AER disrupted normal digit patterning and led to extra postaxial cartilaginous condensations.
Conclusions:
- The Hedgehog (Hh) signaling pathway is present and functional in the developing limb bud ectoderm.
- Hh signaling within the AER is crucial for normal autopod development and digit patterning.
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