転写コファクター複合体CRSPは,強化剤結合タンパク質Sp1の活性化に必須である
1Howard Hughes Medical Institute, University of California at Berkeley, Molecular and Cell Biology, 94720-3204, USA.
Nature
|February 16, 1999
まとめ
研究者らは,遺伝子転写に不可欠な新しいヒトのコアクティベーター複合体,CRSPを発見しました. CRSPは,TFIIDと連携してSp1による転写を活性化することで,コアクティベーターの組み立てのための組み合わせメカニズムを明らかにします.
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
- バイオケミストリー バイオケミストリー
背景:
- メタゾーンにおける遺伝子転写活性化は,複雑で多段階のプロセスです.
- Sp1のような転写増強剤結合因子は,TFIIDサブユニットを含むコアクティベーターを活性化するために必要とします.
- Sp1媒介による転写に必要な追加のコファクターのアイデンティティは,未だに曖昧である.
研究 の 目的:
- Sp1媒介による転写活性化に関与する新しい共因子を特定し,特徴づけること.
- 新しく発見されたコファクター複合体,CRSP.の組成と機能を明らかにするために.
主な方法:
- CRSP複合体の浄化について.
- タンパク質複合体の特徴づけによるサブユニット識別.
- CRSPサブユニットの遺伝子クローンと配列分析.
- コファクター機能を評価するための免疫低下の研究.
主要な成果:
- 新しいヒトコファクター複合体,CRSP (約. 9つのサブユニットからなる700K M(r) が特定されました.
- CRSPは,SP1による転写活性化に不可欠であり,TAFと並行して機能する.
- CRSPサブユニットは,メド7,Rgr1,TFIISを含む酵母媒介体および延長因子とのホモロジーを示しています.
- CRSP p200は,核ホルモン受容体共活性化子ユニット TRIP2/PBP と同一である.
結論:
- CRSPは,Sp1媒介遺伝子転写に必要な重要な共同活性化剤である.
- CRSPのサブユニット構成は,種間の機能ドメインが保存されていることを示唆しています.
- 発見は,転写活性化におけるコアクティベーター複合体の組み合わせ組成機構を示唆している.
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