核クローニングとゲノムの表遺伝的再プログラミング
W M Rideout1, K Eggan, R Jaenisch
1Whitehead Institute for Biomedical Research and, Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.
Science (New York, N.Y.)
|August 11, 2001
まとめ
核移転 (NT) による哺乳類のクローニングは,エピジェネティック再プログラミングのエラーのために頻繁に失敗します. 幹細胞からクローンされた胚は,体細胞からクローンされた胚よりもうまくいきますが,一部の表遺伝子情報は復元できず,発達に影響を及ぼします.
科学分野:
- 生殖生物学 生殖生物学
- 発達生物学 発達生物学とは
- エピジェネティクス エピジェネティクス
背景:
- 哺乳類における核転移 (NT) の成功率は低いため,発達障害を引き起こします.
- クローン哺乳類の異常は,しばしば不完全な表遺伝的再プログラミングと関連している.
研究 の 目的:
- クローン哺乳類におけるエピジェネティック再プログラムと発達上の結果に対するドナー細胞タイプの影響を調査する.
- 核移転後のエピジェネティック修復の限界を特定する.
主な方法:
- 胚性幹細胞から得られたクローン胚の比較と体細胞の比較.
- テロメア長さ,X染色体不活性化など,表遺伝子マーカーの分析.
- クローン胚の発達進行と生存率の評価.
主要な成果:
- 胚性幹細胞からクローンされた胚は,体細胞クローンと比較して,移植後の発達が改善されています.
- テロメアの長さとX染色体不活性化は再プログラムできるが,ゲメティックインプリントは復元されない.
- クローンされた哺乳類では,著しい転写失調が起こりますが,彼らはその期間まで生き延びることができます.
結論:
- エピジェネティック再プログラミングは,成功する哺乳類のクローニングに不可欠であり,ドナー細胞の選択が結果に影響を与える.
- 哺乳類の発達は,特定の値まで表遺伝子異常に対する耐性を示す.
- ゲーメティックインプリントの不完全な回復は,核移転技術の重要な制限を意味します.
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