ディスタルエンハンサーと超保存エクソンは,新しいレトロポゾンから派生しています
Gill Bejerano1, Craig B Lowe, Nadav Ahituv
1Center for Biomolecular Science and Engineering, University of California Santa Cruz, Santa Cruz, California 95064, USA. jill@soe.ucsc.edu
Nature
|April 21, 2006
まとめ
脊椎動物の高度に保存されたゲノム領域は,古代のサルコプテリジアン (Sarcopterygian) の短い間隔の繰り返し要素 (SINEs) から発生した. 4億1千万年以上前に活動していたこれらのレトロポゾンは,制御要素に抽出され,代替的にエクソンがスプライスされ,その進化的起源が明らかになりました.
科学分野:
- ゲノミクスゲノミクスとは
- 進化生物学の進化生物学について
- 分子生物学は分子生物学である.
背景:
- 脊椎動物のゲノムには,多くの高度に保存されたシス調節要素が含まれていますが,その進化的起源,特に無脊椎動物の起源はほとんど不明です.
- 比較ゲノミクスは,何千もの保存された領域を予測しますが,その祖先の配列は,しばしば配列類似性によって追跡できません.
研究 の 目的:
- テトラポッドゲノムにおける保存された非コーディング領域の進化的起源を調査する.
- 高度保存された脊椎動物特有のゲノム配列の源を特定する.
主な方法:
- 比較ゲノミクスは,種間で保存された領域を追跡する.
- 新型短い間隔繰り返し元素 (SINE) のレトロポゾンファミリーの識別と特徴付け.
- マウスエンハンサーアッセイを用いた機能分析で,調節活動のテストを行いました.
- 配列分析は,遺伝子内の代替的にスプライスされたエクソンを識別するために行われます.
主要な成果:
- テトラポッドの保存された非コーディング領域のクラスは,少なくとも4億1000万年前に活動していたサルコプテリジアン特異のSINE家族に由来しています.
- SINEから派生した1つの要素は,神経発達遺伝子のISL1.1の強化剤として機能する.
- 他のSINEコピーは,PCBP2のような遺伝子で,超保存領域を含む,代替的にスプライスされたエクソンとして抽出されています.
結論:
- 移植可能な要素,特にSINEは,機能的なゲノム要素に抽出され,脊椎動物の保存された配列に貢献することができます.
- この研究は,高度に保存された脊椎動物特有のゲノム配列のサブセットのための新しい起源を提供します.
- この発見は,繰り返しの要素と宿主ゲノムとの間のダイナミックな進化的相互作用を強調しています.
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