タイムレスのリズミカルな表現:周期遺伝子の自己調節における昼夜周期を促進するための基礎
A Sehgal1, A Rothenfluh-Hilfiker, M Hunter-Ensor
1Department of Neuroscience, University of Pennsylvania Medical Center, Philadelphia 19104, USA.
まとめ
時計遺伝子のタイムレス (tim) は,ドロソフィラの昼夜リズムにとって極めて重要です. そのRNAの振動がPERタンパク質の蓄積を調節し,日々の遺伝子発現サイクルを保証する.
科学分野:
- クロノバイオロジーはクロノバイオロジーを用います.
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- シルカディアンリズムが,日々の生物学的プロセスを支配する.
- ドロソフィラ・メラノガスターのモデルは,昼間の時計を研究するために広く使用されています.
- "タイムレス" (tim) 遺伝子は,ハエの昼夜系の重要な構成要素である.
研究 の 目的:
- ドロソフィラの昼夜リズムにおける無時間 (tim) 遺伝子の役割を調査する.
- ティムRNAとPERタンパク質発現を制御する規制メカニズムを解明する.
- タイムが昼間の遺伝子転写のタイミングにどのように影響するかを理解する.
主な方法:
- タイムRNAの蓄積パターンの分析.
- タイムRNAリズム・フェーズとピリオドを遺伝子毎のリズムと比較.
- TIMRNAの振動がPERとTIMタンパク質に依存しているかを調べる.
主要な成果:
- ティムRNAの蓄積は,明確な昼夜リズムを示した.
- タイムRNAリズムの相と周期は,per.の相と周期と似ていた.
- timRNAの振動はPERおよびTIMタンパク質の存在に依存しており,フィードバック制御を示しています.
- 周期的な時間表現は,PERタンパク質の蓄積と核への侵入のタイミングを調節した.
結論:
- timは,ドロソフィラの昼夜リズムを確立し維持する上で重要な役割を果たします.
- PERおよびTIMタンパク質を含むフィードバックループが,tim発現を調節する.
- timはタイミングメカニズムとして作用し,PER RNAとタンパク質の蓄積を昼間の異なる時間に分離し,それによって昼間の転写リズムを促進します.
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