ホメオドメインのDNA結合の変動は,配列偏好の高解像度分析によって明らかになりました
Michael F Berger1, Gwenael Badis, Andrew R Gehrke
1Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Cell
|July 1, 2008
まとめ
研究者は,ほとんどのマウスのホームドメインのDNA結合の好みをマッピングし,65の異なる活動を発見しました. この研究は,種間のホメオドメイン結合部位の予測を可能にし,進化的研究を支援しています.
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:
- ホメオドメインは,発達に関与する重要なDNA結合タンパク質である.
- それらの重要性にもかかわらず,それらの正確なDNA配列認識パターンは完全に理解されていません.
- 種間で保存されているホメオドメインは,それらの結合特異性に対する強力な進化的選択を示唆する.
研究 の 目的:
- マウスホメオドメインのDNA結合の好みを包括的に決定する.
- ホメオドメインファミリー内のDNA結合活動の多様性を特定する.
- 異なる種間のホメオドメイン結合部位の予測モデルを開発する.
主な方法:
- ハイ・スループット・シーケンシングは,マウスの168のホメオドメインの結合を,可能なすべての8塩基DNA配列に決定するために使用されました.
- ホメオドメイン結合部位を予測するための計算システムが開発されました.
- 様々な動物種からホメオドメインの拘束プロファイルが推論された.
主要な成果:
- 詳細なDNA結合プロファイルは,マウスホメオドメインの大部分のために生成されました.
- マウスのホメオドメインでは,少なくとも65の異なるDNA結合活動が特定されました.
- 計算システムは,ドロソフィラやC. elegans.などの進化的に遠い生物の結合部位を正確に予測しました.
- ほとんどの知られている動物ホメオドメインの完全な8メア結合プロファイルが推論された.
結論:
- ホメオドメインのDNA結合特異性は豊かで複雑で,有意な変動がある.
- 配列認識の変異は,ホメオドメインの機能的多様性と進化の成功に寄与する可能性がある.
- この研究は,ホメオドメインの機能と進化を理解するための高解像度のリソースを提供します.
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