エクソン媒介によるトランスクリプションの起動
Ana Fiszbein1, Keegan S Krick1, Bridget E Begg1
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02138, USA.
Cell
|December 3, 2019
まとめ
内部エクソンのスプライシングは,転写開始部位 (TSS) を活性化することによって遺伝子発現に影響を与えます. エクソン媒介による転写開始 (EMATS) 現象は,哺乳類におけるプロモーター選択と遺伝子発現レベルに影響を与える.
科学分野:
- 分子生物学
- ゲノミクス
- 進化生物学
背景:
- RNA処理と転写は哺乳類の遺伝子の関連プロセスである.
- スプライシングはRNAの成熟の重要なステップです
研究 の 目的:
- エクソン媒介による転写開始 (EMATS) を記述する.
- プロモーターの選択と遺伝子発現に対する内部エクソンスプライシングの影響を調査する.
- 代替プロモーターの進化におけるスプライシングの役割を理解する.
主な方法:
- 遺伝子の進化と転写開始部位に関する観察研究.
- エクソンスプライシングの実験的抑制
- 新しいスプライスされたエクソンの実験的な創造.
主要な成果:
- 内部エクソンの進化的獲得は,新しい転写開始部位 (TSS) と遺伝子発現の増加と相関する.
- エクソンスプライシングを阻害すると,近接プロモーターからの転写が低下した.
- 新しいスプライスされたエクソンは 暗号的プロモーターからの転写を活性化します
- スプライスされたエクソンの上流にある弱いプロモーターは,最も強い効果を示した.
結論:
- TSSの選択に影響を及ぼします.
- エクソン獲得,喪失,および規制の変化は,哺乳類における代替プロモーターの進化と遺伝子発現に寄与する.
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