まとめ
ドロソフィラ hsp 70 に結合する熱ショック遺伝子転写因子 (HSTF) は,複数の上流部位で協力的な相互作用を伴う. 最大の遺伝子活性化には,TATA近接部位での結合が必要ですが,これだけでは不十分です.
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:
- ドロソフィラ hsp 70 遺伝子は熱ショック遺伝子特異転写因子 (HSTF) によって調節されます.
- HSTF結合は,遺伝子の調節領域内の複数の部位で発生する.
研究 の 目的:
- ドロソフィラ hsp 70遺伝子におけるHSTFの結合親和性と協力相互作用を調査する.
- 転写活性化における個々のHSTF結合部位の役割を決定する.
主な方法:
- 5'および3'削除変異を用いたフットプリント研究.
- アガロース-アクリラミドゲル測定法で結合親和性を決定する.
- 核抽出物と再構成実験によるインビトロ転写アッセイ.
主要な成果:
- 異なる内在的親和性を持つ2つの連続したHSTF結合部位が,TATAホモロジーに近接する55bpドメイン内で特定されました.
- HSTFは,より遠い部位と比較して,TATA近接部位に対する12.5倍以上の親和性を示しています.
- ディスタル部位への結合は協力的であり,近接部位の占有に左右される.
結論:
- TATA近辺のHSTF結合部位は極めて重要であるが,最大 hsp 70 遺伝子転写活性化には不十分である.
- HSTFが複数の部位に協力的に結合することは,ドロソフィラの熱ショック遺伝子の効率的な調節に不可欠です.
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