誘導された多能幹幹細胞における表遺伝子記憶
1Stem Cell Transplantation Program, Division of Pediatric Hematology/Oncology, Manton Center for Orphan Disease Research, Howard Hughes Medical Institute, Children's Hospital Boston and Dana Farber Cancer Institute, Boston, Massachusetts 02115, USA
Nature
|July 21, 2010
まとめ
ソマティック細胞核移転 (SCNT) は,多能性を達成するために,転写因子ベースの再プログラミングよりも効果的です. SCNT由来細胞はエピジェネティックメモリが少ないため,誘発性多能幹細胞 (iPSC) に比べてより広い差別化潜在能力を発揮します.
科学分野:
- エピジェネティクス エピジェネティクス
- 幹細胞生物学 幹細胞生物学
- 発達生物学 発達生物学について
背景:
- 体細胞核移転 (SCNT) と転写因子ベースの再プログラミングは,成人細胞から多能幹細胞を生成する方法である.
- この2つの方法とも,遺伝子の発現に影響を与えるエピジェネティック変異であるゲノムメチレーションをリセットします.
- 再プログラムメカニズムの違いは,その結果生じる多能幹細胞の性質の潜在的な変化を示唆する.
研究 の 目的:
- SCNT由来および誘発性多能幹細胞 (iPSCs) の間における表遺伝的状態と微分の可能性の違いを調査する.
- 起源の体組織からの表遺伝的記憶が,iPSCの性質に影響するかどうかを決定する.
- プラリポテンシーの基本状態の確立におけるSCNTと因数ベースの再プログラミングの有効性を比較する.
主な方法:
- 低通路のiPSCとSCNT由来多能幹細胞におけるDNAメチル化パターンの比較.
- 様々な細胞系に沿った微分化の可能性の評価.
- エピジェネティックメモリリセットのリセットを調査するために,クロマチンを改変する薬剤でiPSCの治療.
主要な成果:
- iPSCは,その起源の体組織から残ったDNAメチル化シグネチャを保持し,ドナー特異的な差異化を促進します.
- iPSCのこの"表遺伝子記憶"は,他の細胞の運命を制限しますが,リセットすることができます.
- SCNT由来の多能幹細胞は,iPSCよりも胚性幹細胞に似ている差別化およびメチル化パターンを示す.
結論:
- SCNTは,多能性の基本状態を確立する上で,因数ベースの再プログラミングよりも効果的です.
- 要素ベースの再プログラミングは,指向された差異化に影響を与えるエピジェネティックメモリを残すことができます.
- これらのエピジェネティック的な違いを理解することは,疾患モデリングと再生医療の応用に不可欠です.
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