組織特異性アルブミン遺伝子発現におけるシス作用のプロモーター要素の役割
P Maire1, J Wuarin, U Schibler
1Département de Biologie Moléculaire, Sciences II, Geneva, Switzerland.
Science (New York, N.Y.)
|April 21, 1989
まとめ
ネズミのアルバミン遺伝子プロモーターに結合する核タンパク質は,組織特異の転写のための階層を示します. 肝細胞核因子1 (HNF-1) とCCAAT/エンハッサー結合タンパク質 (C/EBP) サイトは転写を強く活性化しますが,NF-Yサイトはより低い,より特定の活性化を示します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- マウスアルブミン遺伝子プロモーターには,遺伝子発現の調節に不可欠な複数の核タンパク質結合部位が含まれています.
- これらの結合部位の階層的機能を理解することは,組織特異の転写を解読する鍵です.
- 以前の研究では,プロモーター領域内のいくつかのタンパク質結合部位を特定しました.
研究 の 目的:
- ネズミのアルブミン遺伝子プロモーター内の異なる核タンパク質結合部位の階層的重要性を調査する.
- HNF-1,C/EBP,NF-Yなどの特定の結合部位が,組織特異的なアルブミン遺伝子転写における役割を決定する.
- これらのプロモーター要素の異なるアクティベーションポテンシャルと特異性を解明する.
主な方法:
- 変異したまたはポリマー化されたアルブミンプロモーター要素を含むテンプレートを使用したインビトロ転写アッセイ.
- 肝臓と臓の組織からの核抽出物を用いて,組織特有の結合と活性化を評価する.
- 特定のタンパク質結合部位の変化に基づく転写レベルの比較分析.
主要な成果:
- アルブミン遺伝子転写に影響を与えるタンパク質結合部位の階層が確立されました.
- 肝細胞核因子1 (HNF-1) とCCAAT/エンハンサー結合タンパク質 (C/EBP) の結合部位は,強烈で組織特異的な活性化を示した.
- 核因子Y (NF-Y) の結合部位は,活性化ポテンシャルが低く,組織特異性が低く,肝臓との抽出物でも同様の機能を示した.
- 特定された他の要素は,比較的弱い活性化部位として機能した.
結論:
- アルブミン遺伝子プロモーター要素の機能的階層は,組織特異の転写を決定する.
- HNF-1およびC/EBPは,肝臓特異性アルブミン遺伝子発現の重要なレギュレータである.
- NF-Yは,HNF-1およびC/EBPと比較してより広範な組織適用性を持つアルバミン遺伝子転写に寄与します.
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