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Updated: Jul 19, 2026
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Quantitative PCR-based Assay to Measure Sonic Hedgehog Signaling in Cellular Model of Ciliogenesis
Published on: January 31, 2025
Hippi is essential for node cilia assembly and Sonic hedgehog signaling
Caroline Houde1, Robin J Dickinson, Vicky M Houtzager
1Biochemistry Department, McGill University, Montreal, Canada H3G 1Y6.
Developmental Biology
|October 10, 2006
Summary
Hippi protein is crucial for embryonic development, regulating left-right axis formation and neural tube patterning by influencing cilia assembly and Sonic hedgehog signaling. Its absence leads to developmental defects.
Area of Science:
- Developmental Biology
- Cell Biology
- Genetics
Background:
- Hippi protein acts as an adapter in pro-apoptotic signaling, linked to Huntington disease.
- Its role beyond apoptosis in embryonic development was unexplored.
Purpose of the Study:
- To investigate novel functions of Hippi in embryonic development.
- To elucidate Hippi's role in left-right axis patterning and central nervous system development.
Main Methods:
- Generation and analysis of Hippi knock-out mouse models.
- Examination of embryonic development, including axis patterning and neural tube formation.
- Assessment of monocilia presence and Sonic hedgehog (Shh) pathway activity.
Main Results:
- Hippi deficiency resulted in randomization of embryo turning and heart looping, indicating defective left-right axis patterning.
- Absence of motile monocilia at the embryonic node was observed in Hippi-/- embryos.
- Downregulation of the Sonic hedgehog (Shh) pathway in the neural tube led to impaired ventral neural cell fate.
Conclusions:
- Hippi plays a dual role in embryonic development, essential for cilia assembly and Sonic hedgehog signaling.
- These findings expand the known functions of Hippi beyond its role in apoptosis, highlighting its significance in developmental processes.
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