State Key Laboratory of Chemo/Biosensing & Chemometrics, College of Chemistry & Chemical Engineering, Hunan University, Changsha 410082, People's Republic of China.
Anal Chem. 2023 Feb 21;95(7):3551-3555. doi: 10.1021/acs.analchem.2c05504. Epub 2023 Feb 12.
Nucleic acids are valuable tools for intracellular biomarker detection and gene regulation. Here we propose a new type of protein (avidin)-scaffolded DNA nanostructure (ADN) for imaging the activity of apurinic/apyrimidinic endonuclease 1 (APE1) in live cells. ADN is designed by assembling an avidin-displayed abasic site containing DNA strands labeled with a fluorophore or a quencher via a complementary linker strand. ADN is nonemissive due to the close proximity of fluorophores and quenchers. APE1-mediated cleavage separates the fluorophores from the quenchers, delivering activated fluorescence. In vitro assays show that ADN is responsive to APE1 with high sensitivity and high specificity. ADN can efficiently enter the cells, and its capability to visualize and detect intracellular APE1 activities is demonstrated in drug-treated cells and different cell lines. The modular and easy preparation of our nanostructures would afford a valuable platform for imaging and detecting APE1 activities in live cells.
核酸是用于细胞内生物标志物检测和基因调控的有价值的工具。在这里，我们提出了一种新型的蛋白质（亲和素）支架 DNA 纳米结构（ADN），用于在活细胞中成像脱嘌呤/脱嘧啶内切酶 1（APE1）的活性。ADN 通过组装带有荧光团或猝灭剂的标记有互补接头链的含有碱基的 DNA 链来设计。由于荧光团和猝灭剂的接近，ADN 没有发射。APE1 介导的切割将荧光团与猝灭剂分离，产生激活的荧光。体外实验表明，ADN 对 APE1 具有高灵敏度和高特异性的响应。ADN 可以有效地进入细胞，并且在药物处理的细胞和不同的细胞系中证明了其可视化和检测细胞内 APE1 活性的能力。我们的纳米结构的模块化和易于制备将为在活细胞中成像和检测 APE1 活性提供有价值的平台。
