霊長類のホットスポットモチーフに対する駆動は,PRDM9遺伝子をメオティック再結合に含んでいる
Simon Myers1, Rory Bowden, Afidalina Tumian
1Department of Statistics, Oxford University, 1 South Parks Road, Oxford OX1 3TG, UK. myers@stats.ox.ac.uk
Science (New York, N.Y.)
|January 2, 2010
まとめ
人間とチンパンジーの再結合ホットスポットは,特定のDNAモチーフによって異なります. PRDM9タンパク質は,このモチーフを結合し,中性再結合と急速な進化的変化における種特有の違いを説明します.
科学分野:
- 遺伝学 遺伝学とは
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
背景:
- 遺伝子クロスオーバーが集中するメオティック再結合ホットスポットは,人間とチンパンジーの間で異なっていることが知られている.
- 特定の13塩基対のDNAモチーフは,ヒトの再結合ホットスポットの有意な割合と関連付けられています.
研究 の 目的:
- チンパンジーの既知のヒト再結合ホットスポットモチーフの機能的な違いを調査する.
- 人間とチンパンジーの間の再結合ホットスポットの分岐の基礎となる分子メカニズムを特定する.
- 種特有の再結合パターンを媒介するPRDM9タンパク質の役割を調査する.
主な方法:
- 再結合ホットスポットの位置の違いを特定するための比較ゲノミクス分析.
- 両種における13塩基対モチーフの活性をテストする機能的測定法.
- PRDM9とモチーフの相互作用を評価するためのタンパク質-DNA結合実験.
- PRDM9の進化の変化とそのホットスポット活動との相関性の分析.
主要な成果:
- 人間のホットスポットで活発な13塩基対モチーフは,チンパンジーでは機能せず,ヒトの血統において負の選択を受けている.
- 亜鉛指タンパク質PRDM9が,このモチーフと結合することを示す証拠があります.
- PRDM9の配列の変動は,ヒトとチンパンジーのホットスポット位置の観察された違いと強く関連しています.
- ヒストン改変 (H3K4トリメチル化) に関するPRDM9の役割は,ホットスポット調節のための保存されたメカニズムを示唆する.
結論:
- PRDM9は,ヒトとチンパンジーの再結合ホットスポットの分岐を促す重要な要因である.
- この発見は,PRDM9によって調節される再結合ホットスポットのための保存された真核機構を示唆しています.
- PRDM9における急速な進化的変化は,再結合パターンを形作る進化的力についての疑問を提起する.
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