人間のc-myc遺伝子における転写の早期終結のための配列要求事項
1Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|April 22, 1988
まとめ
研究者らは,ヒトのc-myc遺伝子の特定のDNA配列を特定し,早すぎる転写終了を引き起こす. これらの配列は,エクソン1/イントロン1境界の上流に位置し,より短いRNA分子の生成を調節する.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- トランスクリプション制御
背景:
- 人間のc-myc遺伝子は細胞成長に不可欠であり,がんではしばしば制御不能である.
- 転写の早期終止は,遺伝子発現の既知の規制メカニズムである.
- 終結のための配列要件を理解することは,遺伝子調節を解読する鍵です.
研究 の 目的:
- 人間のc-myc遺伝子における早すぎる転写終止の原因となる配列要素を調査する.
- これらの終端信号の正確な位置と特徴を決定する.
- 断片化されたRNAの原因として,転写終結とRNA処理を区別する.
主な方法:
- 転写を研究するためのXenopus卵細胞注射システム.
- RNAポリメラーゼIIの活性とトランスクリプト3'-エンド形成の分析.
- c-myc遺伝子内の特定のDNA配列の削除分析.
- 核流出アッセイは,ヒト細胞と解剖された卵細胞核で実施されます.
主要な成果:
- 断片化されたRNAは,P1/P2プロモーターの5'端と,エクソン1/イントロン1交差点の近くの3'端を持つ卵細胞で生成される.
- 終結は,RNA処理ではなく,転写終結によって起こります.
- 95塩基領域 (エクソン1/イントロン1に比べて-130から-35まで) は,終止信号を含んでいる.
- 終結は方向性依存であり,異質プロモーターの下流で機能する.
結論:
- ポリ-Tストレッチではなく,特定の上流配列が,c-myc転写終結のための3'端形成の場所を決定する.
- これらの配列は,早すぎる転写終結を制御するシス作用の要素として機能します.
- この発見は,ヒトのc-myc遺伝子の規制メカニズムについての洞察を提供します.
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