酵母とヒトのTFIIDの機能的な違いは,高度に保存された領域に局限しています
B P Cormack1, M Strubin, A S Ponticelli
1Department of Biological Chemistry, Harvard Medical School, Boston, Massachusetts 02115.
Cell
|April 19, 1991
まとめ
保存されたコアドメインにもかかわらず,ヒトのTFIID (トランスクリプションファクターII D) は酵母菌の成長を十分にサポートしていません. N末端領域ではなく,コアドメイン内の種特有の差異が,転写因子活性におけるこの機能的区別の原因である.
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:
- 転写因子II D (TFIID) は,真核生物の遺伝子発現に不可欠な,高度に保存された一般的な転写因子である.
- ユカリオット全体にわたるTFIIDのコアドメインは,高シーケンスの同一性 (>80%) と類似した生化学的特性を共有しています.
研究 の 目的:
- 保存されたコアドメインにもかかわらず,酵母とヒトTFIIDの機能的な違いを調査する.
- TFIID内の特定の領域を特定し,酵母菌における種別機能不適合の原因となる.
主な方法:
- ヒトTFIIDと酵母-ヒトハイブリッドTFIIDコンストラクタを発現する酵母細胞の機能分析.
- TFIID機能の測定として細胞成長の評価 in vivo.
- 機能的決定因子を特定するために,コアドメイン領域の比較分析.
主要な成果:
- 人間のTFIIDを発現する酵母細胞は,内生酵母TFIIDを発現する酵母細胞と比較して,成長が著しく低下しています.
- TFIIDのN末端領域は,コア領域のみが成長をサポートしているため,酵母細胞の生命力にとって不可欠ではありません.
- TFIIDの保存されたコアドメイン内の特定の領域は,観察された種特有の機能的差異に責任があります.
結論:
- 酵母とヒトのTFIIDの機能的不適合は,保存されたコアドメイン内の変異から生じる.
- TFIIDにおけるこれらの種別的差異は,変化したDNA結合親和性または転写機構の構成要素との明確な相互作用から生じる可能性があります.
- これらの変異を理解することで,基本的な転写プロセスの進化と規制の洞察が得られます.
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