ユカリオット前始動複合体の全ゲノム構造と組織
Ho Sung Rhee1, B Franklin Pugh
1Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Nature
|January 20, 2012
まとめ
研究者は,ChIP-exo.exoを使用して,全ゲノムにわたる転写前始動複合体 (PICs) を正確にマッピングしました. これは,PICsを明らかにします.
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
- バイオケミストリー バイオケミストリー
背景:
- 転写前始動複合体 (PIC) は,遺伝子調節に不可欠である.
- PICの全ゲノムにわたる構造的および位置的組織は,依然としてほとんど特徴づけられていない.
- PICの組織を理解することは,遺伝子発現制御の解読に不可欠です.
研究 の 目的:
- トランスクリプション・プレイニシアーション・コンプレックス (PIC) のゲノム位置を正確にマッピングする.
- ユカリオットゲノムにおけるPICの位置的制約と組織的原理を調査する.
- PIC,ヌクレオソーム,および転写開始部位との関係を調査する.
主な方法:
- 高解像度マッピングのためのクロマチン免疫プレシピテート (ChIP-exo) にラムダエクソヌクレアスを適用する.
- サッカロマイセスの6,045のPICのゲノム解析.
- ChIP-exoデータと結晶学モデルと核細胞位置情報との統合.
主要な成果:
- RNAポリメラーゼIIおよび関連因子を含むPICは,プロモーター内に正確に位置し,コーディング領域から除外されました.
- ChIP-exoパターンは,TATAが少ないプロモーターでTATAのような要素を正確に特定しました.
- PICと転写開始部位は,下流の +1 核細胞によって制限され,TATA-box プロモーターでの競争が観察されました.
結論:
- PICは,転写開始部位において,核個体に対して位置的組織が制約されている.
- 核子の位置は,PICの関与と潜在的に転写開始部位の選択に影響を与えます.
- PICのゲノムマッピングは,真の遺伝子を転写ノイズから区別するのに役立ちます.
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