活性プロモーターからの異なった転写
Amy C Seila1, J Mauro Calabrese, Stuart S Levine
1Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science (New York, N.Y.)
|December 6, 2008
まとめ
ほとんどの遺伝子は一方向に転写を開始する. この研究は,タンパク質をコードする遺伝子プロモーターにおける広範な異なった転写を明らかにし,短いRNAが活発なプロモーター領域を横断し,調節のためのバランスの取れた状態を示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- エピジェネティクス エピジェネティクス
背景:
- RNAポリメラーゼII (RNAPII) による転写開始は,伝統的に片方向性と考えられています.
- プロモーター活動と遺伝子調節を制御する正確なメカニズムはまだ調査中です.
研究 の 目的:
- タンパク質をコードする遺伝子プロモーターにおける異なった転写の現象を調査する.
- 転写開始部位関連RNA (TSSa-RNAs) の性質とゲノム位置を特徴付けるために.
主な方法:
- TSSa-RNAの検出と特徴づけのための北極点分析.
- クロマチン免疫降水 (ChIP) は,ヒストン変異 (H3K4me3,H3K79me2) と,プロモーター領域におけるRNAPII占有率を評価する.
主要な成果:
- 広範囲に広がる異なった転写の証拠,感覚と反感覚の両方の短いRNAを生成し,活発なプロモーターの隣接する.
- 20-90核酸からなるTSSa-RNAは,明確な位置バイアスを表している:反感覚ピークは,転写開始部位 (TSS) の上流,感覚ピークは下流である.
- 転写開始の特徴 (RNAPII,H3K4me3) は,TSSa-RNAの位置でコロカライズされ,延長の特徴 (H3K79me2) は,TSSsの下流で発見される.
結論:
- 短距離分散転写は,活性タンパク質をコードする遺伝子プロモーターの共通の特徴である.
- この異なった転写は,後の遺伝子調節のためにプロモーター領域を平衡状態に保つのに寄与する可能性があります.
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