SCF ((FBXL3) 无处不在合酶针对其辅因子口袋中的加密染色体
Weiman Xing1, Luca Busino, Thomas R Hinds
1Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA.
Nature
|March 19, 2013
概括
哺乳动物的加密染色体2 (CRY2) 结构揭示了FBXL3如何准CRY2进行降解,从而影响昼夜时钟. 这种由黄胺二核酸 (FAD) 和周期蛋白 (PERs) 影响的相互作用提供了潜在的药物标.
科学领域:
- 分子生物学分子生物学
- 时间生物学 时间生物学
- 结构生物学 结构生物学
背景情况:
- 加密染色体 (CRYs) 是对哺乳动物的昼夜节律至关重要的黄蛋白,通过与周期 (PER) 蛋白相互作用来调节基因转录.
- SCF ((FBXL3) 泛基因酶复合体降解CRY蛋白,控制昼夜时钟的负反循环.
- CRY-PER相互作用的精确机制以及黄胺二核酸 (FAD) 在CRY功能中的作用仍然不清楚.
研究的目的:
- 阐明哺乳动物CRY2与FAD和FBXL3结合酶复合物的相互作用的结构基础.
- 了解FAD结合和FBXL3介导的CRY2.2的无处不在的功能影响.
- 确定生物钟调节中药理干预的潜在目标.
主要方法:
- 使用X射线晶体学来确定哺乳动物CRY2在apo,FAD-bound和FBXL3-SKP1-复杂状态中的结构.
- 结构分析的重点是FAD结合口袋和CRY2,FBXL3和PER蛋白之间的接口.
- 隐含的生物化学测试用于评估这些相互作用的破坏.
主要成果:
- 哺乳动物CRY2表现出具有开放的辅因子口袋的动态FAD结合,与其他已知的加密染色体不同.
- F-box蛋白FBXL3通过双边相互作用结合CRY2,占据FAD口袋并埋葬PER结合接口.
- 这种相互作用被FAD和PER破坏稳定,表明了复杂的调节机制.
结论:
- 结构洞察力揭示了CRY2无处不在和FBXL3.3降解的新机制.
- FAD,PERs和FBXL3之间的相互作用凸显了哺乳动物昼夜钟的多方面的调节.
- 鉴定到的相互作用部位是开发药物调节昼夜节律的潜在目标.
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