哺乳類の昼夜時計による転写終結のフィードバック調節 PERIOD 複合体
Kiran Padmanabhan1, Maria S Robles, Thomas Westerling
1Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
まとめ
哺乳類の昼夜時計は,PERIOD (PER) とCRYPTOCHROME (CRY) コンプレックスを使用して,転写を抑制する. これらのPER複合体は,直接的に転写終結を制御し,RNAポリメラーゼIIの放出と再起動を阻害する.
科学分野:
- 分子生物学は分子生物学である.
- クロノバイオロジーはクロノバイオロジーを用います.
- 遺伝子規制 遺伝子規制
背景:
- ユカリオットの昼夜時計は,レギュレーションのために転写的フィードバックループに依存しています.
- 哺乳類では,PERIOD (PER) とCRYPTOCHROME (CRY) タンパク質が核複合体を形成し,遺伝子転写を抑制する.
研究 の 目的:
- PER複合体が転写を抑制するメカニズムを調査する.
- 昼間のネガティブなフィードバックにおけるRNAヘリカーゼと転写終結の役割を決定する.
主な方法:
- マウスのPER複合体の組成の分析.
- PerとCryの遺伝子終結部位におけるRNAポリメラーゼIIの行動を研究する.
- PER複合体とSETXの相互作用を調査する.
主要な成果:
- マウスのPER複合体には,RNAヘリコース (DDX5,DHX9),RNAポリメラーゼII,およびプレ-mRNAが含まれています.
- RNAポリメラーゼIIは,昼間のネガティブなフィードバックの間にPerおよびCry遺伝子の終末部位に蓄積する.
- PER複合体のリクルートメントは,転写終結因子であるSETXを阻害し,ポリメラーゼの放出を阻害する.
結論:
- シルカディアン・ネガティブなフィードバックは,転写終結の直接的調節を伴う.
- PER複合体は,終末部位でのRNAポリメラーゼIIの放出を阻害することによって,転写を積極的に抑制する.
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