Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , P. R. China.
Anal Chem. 2019 Dec 3;91(23):15229-15234. doi: 10.1021/acs.analchem.9b04126. Epub 2019 Nov 12.
A robust ATP aptasensor has been successfully constructed for intracellular imaging via the autonomous nonenzymatic cascaded hybridization chain reaction (Ca-HCR) circuit. This compact aptasensor is easily assembled by integrating the sensing module and amplification module, and is furtherly introduced for selective adenosine triphosphate (ATP) assay and for the sensitive tracking of varied ATP expressions in living cells. The ATP-targeting aptamer-encoded sensing module can specifically recognize ATP and release the initiator strand for successively motivating the two-layered HCR (hybridization chain reaction) circuit via the FRET transduction mechanism. The synergistic reaction acceleration of the two HCRs contributes to the high signal gain (amplification efficiency of N). The whole reaction process was modeled and simulated by MATLAB to deeply explore the underlying molecular reaction mechanism, implying that the cascade HCR is sufficient enough to guarantee the ATP-recognition and amplification processes. The Ca-HCR-amplified aptasensor shows high sensitivity and selectivity for in vitro ATP assay, and can monitor these varied ATP expressions in living cells via intracellular imaging technique. Furthermore, the present aptasensor can be easily extended for monitoring other low-abundance biomarkers, which is especially important for precisely understanding these related biological processes.
一种稳健的 ATP 适体传感器已通过自主非酶级联杂交链式反应（Ca-HCR）电路成功构建，用于细胞内成像。这种紧凑的适体传感器可以通过集成传感模块和放大模块轻松组装，并进一步用于选择性腺苷三磷酸（ATP）测定以及在活细胞中敏感跟踪各种 ATP 表达。靶向 ATP 的适体编码传感模块可以特异性识别 ATP，并释放引发链，通过 FRET 转导机制成功地启动双层 HCR（杂交链式反应）电路。两个 HCR 的协同反应加速有助于获得高信号增益（N 的放大效率）。整个反应过程通过 MATLAB 进行建模和模拟，以深入探索潜在的分子反应机制，表明级联 HCR 足以保证 ATP 识别和放大过程。Ca-HCR 放大的适体传感器对体外 ATP 测定具有高灵敏度和选择性，并可以通过细胞内成像技术监测活细胞中的这些不同的 ATP 表达。此外，该适体传感器可以轻松扩展用于监测其他低丰度生物标志物，这对于精确理解这些相关的生物过程尤为重要。
