ホメオドメイン-DNA相互作用の配列特異性

C Desplan¹, J Theis, P H O'Farrell

¹Department of Biochemistry and Biophysics, University of California, San Francisco 94143-0448.

Cell

|September 23, 1988

まとめ

刻まれた遺伝子.

科学分野:

発達生物学発達生物学とは
遺伝学遺伝学とは
分子生物学は分子生物学である.

背景:

ドロソフィラ・メラノガスターの発達遺伝子は,DNA結合活動をコードすることが知られている.
この活動は,発達中の遺伝子調節に極めて重要です.

研究の目的:

刻まれた遺伝子のDNA結合に責任を負う特定のドメインを特定する.
DNA結合部位と刻まれたホメオドメインの特異性を特徴付けるため.
刻まれたホメオドメインと関連するホメオドメインの結合特性を比較する.

主な方法:

埋め込まれた遺伝子の削除コンストラクションを利用した.
機能分析のためにE. coliで発現された融合タンパク質.
決定されたDNA結合部位のコンセンサス配列.
結合分析と競争実験を行いました.

主要な成果:

保存されたホメオドメイン (HD) にDNA結合活動を局所化しました.
拘束サイトコンセンサスを TCAATTAAAT として識別し,grailed 規制領域のクラスターで見つかりました.
コンセンサス配列の隣接するコピーの結合強化が観察されました.
Fushi tarazu (Ftz) ホメオドメインが,いくつかの好みの違いで,類似したサイトを engrailed (En) HDに結合することを発見しました.
EnとFtzの両方のHDは,第2のシーケンスタイプに結合します: TAAの繰り返しです.

結論:

EnとFtz HDsのシーケンス特異性の類似性は,関連するDNA結合タンパク質が類似した特異性を共有することを示唆しています.
結合部位に関する関連する調節タンパク質間の競争は,遺伝子調節の結果を決定する可能性があります.

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