プロモーターにおける不安定なタンデム反復は,転写進化性を授与する
Marcelo D Vinces1, Matthieu Legendre, Marina Caldara
1FAS Center for Systems Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|May 30, 2009
まとめ
タンデムDNAの繰り返しは,酵母遺伝子のプロモーター領域で一般的であり,遺伝子発現と進化に影響を与えます. これらの繰り返しの変異は,遺伝子活動とクロマチンの構造を変化させ,進化的適応を促進します.
科学分野:
- ゲノミクスゲノミクスとは
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- 配列で繰り返されるDNA配列は,突然変異が起こる傾向があります.
- 遺伝子の上流にあるプロモーター領域は,遺伝子調節に極めて重要です.
研究 の 目的:
- Saccharomyces cerevisiaeの遺伝子プロモーターにおけるタンデムリピートの発生率と機能を調査する.
- これらの繰り返しが遺伝子発現とクロマチンの構造にどのように影響するかを理解する.
主な方法:
- 酵母ゲノムにおけるタンデムリピートに関するバイオ情報学的検索.
- 遺伝子のプロモーターを繰り返し濃縮するための分析.
- 繰り返しの存在と転写分岐と核細胞の位置づけの相関.
主要な成果:
- タンデムリピートは酵母プロモーター領域 (プロモーターの25%まで) で著しく濃縮されています.
- 繰り返し含有プロモーターを持つ遺伝子は,より高い転写分岐率を示しています.
- 繰り返しの長さの変動は,遺伝子発現レベルと局所的な核細胞体の位置づけに影響します.
結論:
- タンデム繰り返しは,遺伝子プロモーター内のダイナミックな要素である.
- これらの繰り返しは,クロマチンの構造を調節することによって,遺伝子発現の進化的調整を容易にすることができます.
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