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Updated: Jun 16, 2026
12:21
Feeder-free Derivation of Melanocytes from Human Pluripotent Stem Cells
Published on: March 3, 2016
Key roles for transforming growth factor beta in melanocyte stem cell maintenance
Emi K Nishimura1, Misa Suzuki, Vivien Igras
1Department of Stem Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10 Kandasurugadai, Chiyoda-ku, Tokyo 101-0062, Japan. nishscm@tmd.ac.jp
Cell Stem Cell
|February 11, 2010
Summary
Transforming growth factor beta (TGF-beta) signaling maintains melanocyte stem cell quiescence and immaturity, crucial for hair pigmentation. Disrupting this pathway leads to hair graying.
Area of Science:
- Stem cell biology
- Dermatology
- Molecular biology
Background:
- Melanocyte stem cells (MSCs) in hair follicles regulate hair pigmentation.
- Defects in MSCs lead to hair graying.
- The role of niche factors in MSC quiescence is not fully understood.
Purpose of the Study:
- To investigate the role of transforming growth factor beta (TGF-beta) signaling in MSC quiescence and immaturity.
- To elucidate the molecular mechanisms by which TGF-beta regulates MSCs.
- To determine the in vivo relevance of TGF-beta signaling in hair pigmentation.
Main Methods:
- In vitro studies using cell culture to assess TGF-beta effects on MSCs.
- In vivo studies using mouse models with targeted gene deficiencies.
- Analysis of gene expression (MITF, melanogenic genes) and cell cycle status.
- Assessment of hair pigmentation and MSC characteristics.
Main Results:
- TGF-beta induces reversible cell cycle arrest in MSCs in vitro.
- TGF-beta downregulates MITF and melanogenic genes, promoting an immature phenotype.
- TGF-beta signaling is activated in quiescent MSCs during the hair cycle, requiring Bcl2 for survival.
- Deficiency in TGF-beta type II receptor (TGFbRII) in MSCs impairs immaturity maintenance and causes mild hair graying.
Conclusions:
- Niche-derived TGF-beta signaling is a key regulator of MSC immaturity and quiescence.
- TGF-beta pathway is essential for maintaining hair pigmentation by regulating MSC behavior.
- Understanding TGF-beta signaling offers potential therapeutic targets for hair graying.
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