2つのたばこDNA結合タンパク質は,核因子CREBと同型である
1Laboratory of Plant Molecular Biology, Rockefeller University, New York 10021.
Nature
|August 31, 1989
まとめ
研究者らは,TGA1aとTGA1bという2つのたばこタンパク質を特定し,根の遺伝子発現に不可欠な特定のDNA配列 (as-1) に結合している. TGA1aは,以前に特定されたASF-1因子の強力な候補であり,根特異的な遺伝子調節を説明します.
科学分野:
- 植物分子生物学 植物分子生物学
- 遺伝子規制 遺伝子規制
- 転写因子 トランスクリプション・ファクター
背景:
- カリフラワーモザイクウイルス (CaMV) 35Sプロモーターには,根特有の遺伝子発現に責任を持つ重要な規制要素,as-1が含まれています.
- タンパク質因子ASF-1は,as-1に結合し,その機能と相関する in vivo のタンパク質因子である.
研究 の 目的:
- as-1配列に結合するタンパク質を分離し,特徴づけること.
- 根の遺伝子発現を調節するASF-1の機能の分子基盤を特定する.
主な方法:
- TGACG配列特異の結合タンパク質をコードするたばこ補完DNA (cDNA) クローンの分離.
- タンパク質の構造を決定するために,cDNAクローンの配列分析.
- タンパク質とDNAの相互作用を評価するためのインビトロ結合測定法.
主要な成果:
- タバコからTGA1aとTGA1bという2つのTGACG配列特異の結合タンパク質が分離されました.
- 配列解析により,TGA1aとTGA1bの両方が,既知の転写因子とレウシン-ジッパー領域に同質的な基本領域を有することが明らかになりました.
- TGA1aはASF-1因子と一致する結合特異性を示し,as-1機能におけるその役割を示唆しています.
結論:
- TGA1aとTGA1bは,as-1規制要素と結合する新しい転写因子です.
- TGA1aはASF-1タンパク質の有力候補であり,as-1要素によって授与される根特異遺伝子発現を媒介する.
- これらの発見は,植物根の遺伝子発現の調節に関する分子洞察を提供します.
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