Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
J Am Chem Soc. 2022 Apr 6;144(13):5887-5892. doi: 10.1021/jacs.1c12659. Epub 2022 Mar 8.
Construction of complex DNA circuits is difficult due to unintended hybridization and degradation by enzymes under biological conditions. We herein report a hybridization chain reaction (HCR) circuit composed of left-handed d-threoninol nucleic acid (d-TNA), which is orthogonal to right-handed DNA and RNA. Because of its high thermal stability, use of an TNA hairpin with a short 7 base-pair stem ensured clear ON-OFF control of the HCR circuit. The TNA circuit was stable against nucleases. A circuit based on right-handed l-threoninol nucleic acid (l-TNA) was also designed, and high orthogonality between d- and l-TNA HCRs was confirmed by activation of each TNA HCR via a corresponding input strand. A dual OR logic gate was successfully established using serinol nucleic acid (SNA), which could initiate both d- and l-TNA circuits. The d-TNA HCR was used for an RNA-dependent signal amplification system via the SNA interface. The design resulted in 80% yield of the cascade reaction in 3000 s without a significant leak. This work represents the first example of use of heterochiral HCR circuits for detection of RNA molecules. The method has potential for direct visualization of RNA and the FISH method.
由于在生物条件下非预期的杂交和酶降解，复杂 DNA 电路的构建较为困难。我们在此报告了一个由左手 d-苏糖醇核酸（d-TNA）组成的杂交链式反应（HCR）电路，它与右手 DNA 和 RNA 正交。由于其高热稳定性，使用具有短 7 个碱基对茎的 TNA 发夹确保了 HCR 电路的明确开-关控制。TNA 电路可抵抗核酸酶。还设计了基于右手 l-苏糖醇核酸（l-TNA）的电路，并通过相应的输入链激活每个 TNA HCR 来证实 d-和 l-TNA HCR 之间的高度正交性。使用丝氨酸核酸（SNA）成功建立了双 OR 逻辑门，它可以启动 d-TNA 和 l-TNA 电路。通过 SNA 接口，将 d-TNA HCR 用于 RNA 依赖性信号放大系统。该设计在 3000 秒内实现了 80%的级联反应产率，而没有明显的泄漏。这项工作代表了首次使用异手性 HCR 电路检测 RNA 分子的实例。该方法有望直接可视化 RNA 和 FISH 方法。
