ニッチ誘発の細胞死と上皮のファゴシトーシスは,毛皮の幹細胞プールを調節する
Kailin R Mesa1, Panteleimon Rompolas1, Giovanni Zito2
1Department of Genetics, Yale School of Medicine, New Haven, Connecticut 06510, USA.
Nature
|April 8, 2015
まとめ
ホメオスタシスにとって極めて重要な組織回帰は,分化とアポトーシスによる上皮細胞死を含みます. 基礎細胞は死にかけている隣人を除去し,成長因子ベータシグナリングの変容がこのプロセスを駆動します.
科学分野:
- 細胞生物学 細胞生物学
- 発達生物学 発達生物学とは
- 組織ホメオスタシス
背景:
- 組織ホメオスタシスは,細胞の成長と除去 (回帰) の間のバランスに依存しています.
- 生理学的組織回帰を制御する細胞および分子機構は,ほとんど不明です.
- マウスの毛皮は,循環性組織の回帰と再生を研究するためのモデルシステムを提供します.
研究 の 目的:
- 生理学的組織回帰を駆動する細胞の行動と分子信号を解明する.
- ヘアフォリキュルの回帰過程における上皮細胞除去のメカニズムを調査する.
- 幹細胞プールと組織ホメオスタシスの調節における回帰の役割を理解する.
主な方法:
- 生きたマウスの腸内顕微鏡検査で,回帰の動態を観察する.
- 重要なシグナル伝達経路を特定するための細胞および遺伝的アブレーション技術.
- 皮質細胞の分化,アポプトーシス,ファゴシトーシスの分析.
主要な成果:
- 毛皮の回帰は,上基底細胞の分化と基底細胞のアポトーシスを通して,ほとんどの上皮細胞を排除します.
- 基礎上皮質細胞はファゴサイト活動を示し,隣接する死にゆく細胞を浄化します.
- トランスフォーミング成長因子β (TGF-β) 信号伝達とメゼンキマクロストラックは,上皮細胞死亡の外部誘発因子として特定されました.
- 逆行は幹細胞のプールを積極的に減少させ,逆行を抑制すると,再生可能な基礎上皮細胞の蓄積につながります.
結論:
- 組織回帰は,異なる細胞死機構と基礎細胞によるファゴサイトクリアランスを含む制御されたプロセスです.
- TGF-βシグナル伝達は,回帰媒介細胞死を誘発する上で重要な役割を果たします.
- 再帰は,幹細胞数を制御し,組織ホメオスタシスを維持し,成長を相殺するために不可欠です.
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