对于CBP KIX域的高亲和性联体的结合模式和转录激活潜力
Heather M Volkman1, Stacey E Rutledge, Alanna Schepartz
1Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA.
Journal of the American Chemical Society
|March 31, 2005
概括
新的配体,PPKID4 (((P) 和PPKID6 (((U),模仿CREB KID激活域与CBP KIX结合. PPKID4 (((P) 与KID (((P) 相似地结合,而PPKID6 (((U) 则与一个不同的区域结合,影响转录激活功率.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- CREB KID激活域 (KID(P)) 与CBP的KIX域相互作用,以调节转录.
- 工程结合体PPKID4 (((P) (4 (((P)) 和PPKID6 (((U) (6 (((U)) 在胰腺折叠支架上呈现KID (((P) α-螺旋表位.
- 这些配体与CBP KIX (KIX) 结合,并与KID ((P)) 竞争.
研究的目的:
- 为了研究4(P) 和6(U) 与CBP KIX的结合方式和方向.
- 评估这些工程配体的转录激活潜力.
- 了解结合亲和力和转录活动之间的关系.
主要方法:
- 使用KIX变体和修改的4(P) 连接体的平衡结合实验.
- 对连接体结合方式和结构影响的分析.
- 在HEK293细胞中进行转录激活测定,使用GAL4DNA结合域融合蛋白.
主要成果:
- 4(P) 绑定KIX模仿KID(P) 绑定,而6(U) 绑定一个重叠但不同的区域.
- 4(P) 在KIX结合后采用胰腺折叠结构.
- 4 (((P) 是p300/CBP依赖转录的强有力的激活剂,而6 (((U) 尽管具有相似的结合亲和力,但效果较差.
结论:
- 配体对KIX的结合方式和方向显著影响转录激活.
- 虽然结合亲和力至关重要,但它不是KIX-依赖的转录输出的唯一决定因素.
- 工程配体提供了对蛋白质-蛋白质相互作用和转录调节机制的见解.
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