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Quantitative PCR-based Assay to Measure Sonic Hedgehog Signaling in Cellular Model of Ciliogenesis
Published on: January 31, 2025
The Hedgehog protein family
1Department of Biosciences and Nutrition, Karolinska Institutet, and School of Life Sciences, Södertörn University, Hälsovägen 7, SE-141 57 Huddinge, Sweden. thomas.burglin@ki.se
Genome Biology
|December 2, 2008
Summary
The Hedgehog (Hh) signaling pathway, crucial for animal development, involves HhN and HhC protein domains. This pathway regulates gene expression via transcription factors like Gli proteins.
Area of Science:
- Developmental Biology
- Molecular Biology
- Biochemistry
Background:
- The Hedgehog (Hh) pathway is a fundamental signal transduction pathway essential for animal development.
- It plays roles in stem-cell maintenance and is implicated in carcinogenesis.
- Hh proteins, found across metazoa, consist of signaling (HhN) and autocatalytic (HhC) domains.
Purpose of the Study:
- To elucidate the structure and function of Hedgehog pathway proteins.
- To explore the evolutionary origins and relationships of Hh and related Hog proteins.
- To detail the molecular mechanisms of Hh signal transduction.
Main Methods:
- Bioinformatic analysis of protein domains (HhN, HhC, Hint, Hog).
- Comparative evolutionary analysis of Hh and Hog families across different taxa.
- Description of post-translational modifications (cholesterol, palmitate) and their roles.
Main Results:
- HhC shares similarity with self-splicing inteins (Hint domain).
- Hog proteins, distinct from Hh, possess a Hog domain similar to HhC but lack HhN.
- Hh pathway activation involves receptor binding (Patched, Smoothened) and downstream transcription factors (Ci, Gli).
Conclusions:
- The Hh pathway is conserved across metazoans, with Hh family emerging in early evolution.
- Hog proteins represent a broader class of Hint domain-containing proteins found in protists and eukaryotes.
- Understanding Hh signaling provides insights into development, stem cell biology, and cancer.
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