シルカディアンクロック: 2つのフィードバックループの物語
1Department of Neurobiology and Physiology, Northwestern University, Evanston, IL 60208, USA.
Cell
|February 13, 2003
まとめ
科学者たちは,日中時計の第2回フィードバックループのキープレーヤーを特定しました. この研究は,ドロソフィラ (果物ハエ) の毎日のリズムを駆動する転写メカニズムを明らかにしています.
科学分野:
- クロノバイオロジー クロノバイオロジー
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- シルカディアンクロックは,ほとんどの生物の毎日の生理リズムを調節する.
- これらの時計は,しばしば転写フィードバックループとしてモデル化されます.
- ドロソフィラでは,第1回転写ループの制御期間の発現がよく理解されています.
研究 の 目的:
- ドロソフィラの昼間時計における第2回転写フィードバックループの構成要素とメカニズムを解明する.
- この第二のループに関与する特定の転写活性化剤と抑制剤を特定するために.
主な方法:
- 調節因子を特定するために,ドロソフィラの遺伝子スクリーンを利用しました.
- 相互作用と機能を確認するために分子および生化学分析を行った.
- フィードバックループのダイナミクスを理解するために遺伝子発現パターンを測定した.
主要な成果:
- 第2回フィードバックループに不可欠な新しい転写活性化剤を特定しました.
- アクティベータと協調して機能する特定の転写抑制器を特徴付けました.
- クロック遺伝子発現の調節におけるこれらの因子の相互依存性を実証した.
結論:
- 第2のフィードバックループは,ドロソフィラの堅固な昼夜リズムに不可欠です.
- トランスクリプションの活性化と抑制のバランスが,時計の第2ループを統制する.
- これらの発見は,ドロソフィラの昼間時計のより完全なモデルを提供します.
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