Structure-switching signaling aptamers
Structure-switching signaling aptamers
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DOI：
10.1021/ja028962o
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发表时间：
2003-04-23
影响因子：
15
通讯作者：
Li, YF
中科院分区：
文献类型：
--
作者：
Nutiu, R;Li, YF
适体是具有确定的三级结构的单链核酸，用于选择性结合靶分子。适体还能够结合互补DNA序列以形成双链体结构。在这份报告中，我们描述了一种策略，用于设计基于适体的荧光报告功能的开关结构从DNA/DNA双链体的DNA/目标复合物。双链体在荧光团标记的DNA适体和用淬灭部分修饰的小寡核苷酸（表示为QDNA）之间形成。当靶不存在时，适体与QDNA结合，使荧光团和猝灭剂紧密接近以实现最大荧光猝灭。当引入靶标时，适体优选形成适体-靶标复合物。适体的结合配偶体的转换与由于QDNA解离而产生的强荧光信号一起发生。在这里，我们报告的几个结构转换报告从两个现有的DNA适体的制备。我们的设计策略是很容易概括的任何适体没有事先了解其二级或三级结构，并应适合于开发基于适体的实时传感应用的报告。
Aptamers are single-stranded nucleic acids with defined tertiary structures for selective binding to target molecules. Aptamers; are also able to bind a complementary DNA sequence to form a duplex structure. In this report, we describe a strategy for designing aptamer-based fluorescent reporters that function by switching structures from DNA/DNA duplex to DNA/target complex. The duplex is formed between a fluorophore-labeled DNA aptamer and a small oligonucleotide modified with a quenching moiety (denoted QDNA). When the target is absent, the aptamer binds to QDNA, bringing the fluorophore and the quencher into close proximity for maximum fluorescence quenching. When the target is introduced, the aptamer prefers to form the aptamer-target complex. The switch of the binding partners for the aptamer occurs in conjunction with the generation of a strong fluorescence signal owing to the dissociation of QDNA. Herein, we report on the preparation of several structure-switching reporters from two existing DNA aptamers. Our design strategy is easy to generalize for any aptamer without prior knowledge of its secondary or tertiary structure, and should be suited for the development of aptamer-based reporters for real-time sensing applications.