Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115, USA.
Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nat Chem. 2018 Feb;10(2):155-164. doi: 10.1038/nchem.2872. Epub 2017 Nov 6.
DNA performs diverse functional roles in biology, nanotechnology and biotechnology, but current methods for autonomously synthesizing arbitrary single-stranded DNA are limited. Here, we introduce the concept of primer exchange reaction (PER) cascades, which grow nascent single-stranded DNA with user-specified sequences following prescribed reaction pathways. PER synthesis happens in a programmable, autonomous, in situ and environmentally responsive fashion, providing a platform for engineering molecular circuits and devices with a wide range of sensing, monitoring, recording, signal-processing and actuation capabilities. We experimentally demonstrate a nanodevice that transduces the detection of a trigger RNA into the production of a DNAzyme that degrades an independent RNA substrate, a signal amplifier that conditionally synthesizes long fluorescent strands only in the presence of a particular RNA signal, molecular computing circuits that evaluate logic (AND, OR, NOT) combinations of RNA inputs, and a temporal molecular event recorder that records in the PER transcript the order in which distinct RNA inputs are sequentially detected.
DNA 在生物学、纳米技术和生物技术中发挥着多样化的功能作用，但目前自主合成任意单链 DNA 的方法有限。在这里，我们引入了引物交换反应 (PER) 级联的概念，该级联按照预定的反应途径生长具有用户指定序列的新生单链 DNA。PER 合成以可编程、自主、原位和环境响应的方式发生，为工程分子电路和设备提供了一个平台，具有广泛的传感、监测、记录、信号处理和致动功能。我们通过实验证明了一种纳米器件，该器件将触发 RNA 的检测转换为产生 DNA 酶，该酶降解独立的 RNA 底物，信号放大器仅在存在特定 RNA 信号的情况下条件合成长荧光链，评估 RNA 输入逻辑（与、或、非）组合的分子计算电路，以及时间分子事件记录器，该记录器在 PER 转录本中记录不同 RNA 输入依次被检测的顺序。
