离子响应DNA结合在指融合蛋白中的离子响应DNA结合
Akira Onoda1, Nozomi Arai, Naoto Shimazu
1Department of Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan.
Journal of the American Chemical Society
|November 25, 2005
概括
研究人员设计了对有反应的指蛋白来控制DNA结合. 这些新型的融合蛋白体现出可调节的DNA结合亲和力,这种亲和力由离子度调节,为先进的人工转录因子铺平了道路.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 蛋白质工程是指蛋白质工程.
背景情况:
- 指蛋白对于DNA识别和基因调节至关重要.
- 开发可控制的DNA结合蛋白对于合成生物学和基因治疗至关重要.
- 离子可以用作生物开关来调节蛋白质功能.
研究的目的:
- 为了设计具有响应DNA结合能力的新指融合蛋白质.
- 研究这些融合蛋白的结构完整性和折叠.
- 为了评估DNA结合亲和力的Ca-依赖调制.
主要方法:
- 紫外光谱学和循环二元化 (CD) 实验用于结构分析.
- 核磁共振 (NMR) 光谱和结构计算用于详细的折叠研究.
- 电泳运动移位试验 (EMSA) 用于在不同的Ca2+度下量化DNA结合亲和力.
主要成果:
- 融合蛋白F2-Tn表现出具有集成Ca-结合域的原生指折叠.
- 两根手指的托罗因融合蛋白 (F1F2-Tn) 显示了对Ca-响应的DNA结合.
- F1F2-Tn的解离常数 (Kd) 在没有Ca2+的情况下为5.8nM,在100等 Ca2+的情况下为13nM.
结论:
- 人工设计的融合指蛋白包含一个Ca-结合域,表现出Ca-响应的DNA结合.
- 这项工作为用开关构建基于指的人工转录因子提供了基础.
- 这些工程蛋白质为精确,外部控制的基因调节提供了一种新的机制.
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