TFIIICは,クロマチンによるU6 snRNA転写の抑制を緩和する
A F Burnol1, F Margottin, J Huet
1Département de Biologie Cellulaire et Moléculaire, Centre d'Etudes de Saclay, Gif-sur-Yvette, France.
Nature
|April 1, 1993
まとめ
酵母U6小核RNA遺伝子転写は,クロマチンに組み合わさるときに転写因子 (TF) IIICを必要とします. この発見は,以前の不一致を説明し,遺伝子活性化におけるTFIIICの新しい役割を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- クロマチンの構造 クロマチンの構造
背景:
- イーストのU6小核 (sn) RNA遺伝子 (SNR6) はRNAポリメラーゼIIIによって転写される.
- TATAボックスと下流のBブロック要素を有しており,RNAポリメラーゼIIIで転写される遺伝子では珍しい.
- In vitro転写研究では,TFIIICがU6 snRNA合成に不可欠ではないことが示唆されました.
研究 の 目的:
- U6 snRNA遺伝子転写におけるクロマチンの構造の役割を調査する.
- TFIIICの必要性に関する in vitroとin vivoの発見の間の不一致を解決する.
- クロマチンの文脈におけるBブロック要素の機能を解明する.
主な方法:
- 核子の再構成とクロマチンの組み立て実験.
- 浄化された転写因子を用いたインビトロ転写アッセイ.
- TFIIICとBブロックの完全性に対するU6 snRNA合成依存性の分析.
主要な成果:
- U6 snRNA合成は,核細胞の再構成またはクロマチンの組立の後,転写因子 (TF) IIICに依存するようになった.
- 下流のBブロック要素の整合性は,組み立てられたクロマチンの文脈での転写に不可欠でした.
- これらの結果は,以前の in vitro および in vivo 観測と一致しています.
結論:
- クロマチンの組立は,U6 snRNAの遺伝子転写においてTFIIICの要求を伴う.
- TFIIICは,染色体環境内のU6 snRNA遺伝子を活性化するのに重要な役割を果たします.
- この研究は,クロマチンの構造によって媒介される遺伝子調節におけるTFIIICの新しい機能を強調しています.
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