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Updated: May 31, 2026

11:39
Chromatin Immunoprecipitation (ChIP) in Mouse T-cell Lines
Published on: June 17, 2017
クロマチンのランドマークと,ヒト細胞のほとんどのプロモーターで転写を開始する
Matthew G Guenther1, Stuart S Levine, Laurie A Boyer
1Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
Cell
|July 17, 2007
まとめ
ほとんどのヒトの遺伝子は,以前は不活性と考えられていたものでさえ,転写を開始します. この全ゲノム分析は,トランスクリプションの開始がヒト細胞全体で一般的なイベントであり,遺伝子調節に影響を及ぼすことを明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- ゲノミクスゲノミクスとは
- エピジェネティクス エピジェネティクス
背景:
- 遺伝子調節を理解することは,細胞の機能と発達にとって極めて重要です.
- 以前の仮定では,多くのタンパク質をコードする遺伝子が転写的に沈黙していることを示唆していました.
- 全体的な遺伝子発現における転写始動の役割は不明のままである.
研究 の 目的:
- ヒトゲノム全体の転写開始の範囲を調査する.
- 初期と延長段階での遺伝子発現を制御する規制メカニズムを特定する.
- 転写を開始することを積極的に阻止されている遺伝子を特徴付ける.
主な方法:
- 人間の胚性幹細胞と微分細胞の全ゲノム分析.
- ヒストン変異 (H3K4me3,H3K9,14Ac,H3K36me3) と,遺伝子プロモーターのRNAポリメラーゼII占有率を検出するためのクロマチンの免疫プレシピテーション.
- 完全な長さのトランスクリプトの生産の分析.
主要な成果:
- 不活性であると推定されるものを含むほとんどのタンパク質をコードする遺伝子は,転写開始の証拠を示しています.
- 特定のヒストンの改変とRNAポリメラーゼIIを持つ核細胞は,ほとんどの遺伝子のプロモーターをマークします.
- 遺伝子のサブセットは延長 (H3K36me3で示される) に進み,他のものは開始するが延長しないので,開始後の規制を示唆する.
- 異なったクラスの遺伝子は,初期段階において積極的に抑制される.
- これらの発見は,幹細胞と微分細胞の両方において一貫しています.
結論:
- トランスクリプションの開始は,ヒト細胞の広範な現象であり,ほとんどのタンパク質をコードする遺伝子で発生します.
- 遺伝子発現は,特に発達のレギュレーターでは,発症後の段階で調節されることが多い.
- 転写開始を防ぐメカニズムは,遺伝子のサブセットに存在する.
- この研究は,ヒトゲノムにおける基礎転写活動に関する我々の理解を再定義する.
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