Selective recognition of c-MYC Pu22 G-quadruplex by a fluorescent probe
Selective recognition of c-MYC Pu22 G-quadruplex by a fluorescent probe
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荧光探针选择性识别 c-MYC Pu22 G-四链体。
DOI：
10.1093/nar/gkz059
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发表时间：
2019-03-18
影响因子：
14.9
通讯作者：
Wei, Dengguo
中科院分区：
文献类型：
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作者：
Zhai, Qianqian;Gao, Chao;Wei, Dengguo
核酸模拟荧光蛋白是定位和成像细胞中功能性生物分子的重要工具。在模拟物中形成的内部g -四重奏与外源荧光团探针之间的堆叠构成了荧光发射的基础。识别的精度取决于探针选择性地靶向拟态物中的特定g -四重体。然而，在体外和体内具有高选择性识别g -四重体的探针的设计仍然是一个挑战。通过基于结构的筛选和优化，我们确定了一种发光荧光探针9CI，它在体外和体外都能选择性识别c-MYC Pu22 g -四重体。结合后，生物相容性探针发出蓝色和绿色荧光，激发波长为405 nm。以9CI和c-MYC Pu22 g -四重复合物为荧光响应核心，构建了一种荧光蛋白的DNA模拟物，成功地在细胞外周定位了一个功能适配体。识别机理分析表明，高选择性和强荧光响应是由动力学匹配、动态相互作用和最终叠加的整个识别过程决定的。该研究表明，单堆叠状态和动态识别过程对于设计具有高选择性的特定g -四联体结构的荧光探针或配体至关重要。
Nucleic acid mimics of fluorescent proteins can be valuable tools to locate and image functional biomolecules in cells. Stacking between the internal G-quartet, formed in the mimics, and the exogenous fluorophore probes constitutes the basis for fluorescence emission. The precision of recognition depends upon probes selectively targeting the specific G-quadruplex in the mimics. However, the design of probes recognizing a G-quadruplex with high selectivity in vitro and in vivo remains a challenge. Through structure-based screening and optimization, we identified a light-up fluorescent probe, 9CI that selectively recognizes c-MYC Pu22 G-quadruplex both in vitro and ex vivo. Upon binding, the biocompatible probe emits both blue and green fluorescence with the excitation at 405 nm. With 9CI and c-MYC Pu22 G-quadruplex complex as the fluorescent response core, a DNA mimic of fluorescent proteins was constructed, which succeeded in locating a functional aptamer on the cellular periphery. The recognition mechanism analysis suggested the high selectivity and strong fluorescence response was attributed to the entire recognition process consisting of the kinetic match, dynamic interaction, and the final stacking. This study implies both the single stacking state and the dynamic recognition process are crucial for designing fluorescent probes or ligands with high selectivity for a specific G-quadruplex structure.