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Folding Keratin Gene Clusters during Skin Regional Specification
Ya-Chen Liang1, Ping Wu2, Gee-Way Lin3
1Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Integrative Stem Cell Center, China Medical University and Hospital, China Medical University, Taichung 404, Taiwan.
Developmental Cell
|June 10, 2020
Summary
Epigenetics guides avian skin regionalization through distinct enhancer and chromatin looping strategies for β-keratin gene clusters, mapping body surfaces.
Area of Science:
- Developmental Biology
- Epigenetics
- Genomics
Background:
- Regional specification is crucial for skin development, regeneration, and evolution.
- The role of epigenetics in avian skin regional specification was previously unknown.
Purpose of the Study:
- To investigate the epigenetic mechanisms regulating β-keratin gene clusters in avian epidermis.
- To elucidate how macro- and micro-regional specificities are established in skin development.
Main Methods:
- Analysis of β-keratin gene clusters in avian epidermis.
- Investigation of enhancer activity and temporospatial chromatin looping.
- Gene perturbation experiments to assess functional roles.
Main Results:
- Two strategies regulate β-keratin gene clusters: enhancers for macro-regional specificity (scales, feathers) and chromatin looping for micro-regional specificity within feathers.
- A three-factor model involving competence factors, regional specifiers, and chromatin regulators explains regional specification.
- Gene perturbations led to disruptions in morphogenesis and histo-differentiation.
Conclusions:
- Epigenetic regulation, via enhancers and chromatin looping, is critical for establishing regional identities in avian skin.
- This study provides a paradigm for understanding how large gene clusters are regulated to map body surfaces.
- The findings advance knowledge of skin development and evolutionary processes.
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