Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
J Am Chem Soc. 2013 Sep 18;135(37):13628-31. doi: 10.1021/ja406053b. Epub 2013 Sep 9.
Most of the dynamic DNA devices are rationally constructed by utilizing toehold-mediated DNA strand displacement reactions. However, such approaches have been mainly limited to the operation with double-stranded hybridization and lack the versatility of DNA scaffold responses for additional levels of controlling DNA strand displacement reactions. Herein, we propose a toehold activation strategy based on the DNA tetraplex (G-quadruplex or i-motif), where the toehold domain is designed by attaching a complementary single-stranded segment (CS) to a G-rich/C-rich segment. Modulating G-quartet/C·C(+) numbers and/or the CS lengths can easily tune the strand displacement kinetics. This scheme allows fine control of DNA strand displacement rates over 2 orders of magnitude by adjusting the concentration of various environmental stimuli. This strategy expands the rule set of designing dynamic DNA devices and will be useful in building diverse environmental stimuli-fuelled molecular devices.
大多数动态 DNA 器件都是通过利用引发链置换反应的结合位介导的 DNA 链置换反应来合理构建的。然而，这些方法主要限于双链杂交的操作，并且缺乏 DNA 支架反应的多功能性，无法对 DNA 链置换反应进行额外水平的控制。在此，我们提出了一种基于 DNA 四链体（G-四联体或 i- 基序）的引发链激活策略，其中通过将互补单链片段（CS）连接到富含 G/C 的片段上来设计引发结合位。调节 G-四联体/C·C(+)的数量和/或 CS 的长度可以通过调节各种环境刺激物的浓度轻松调整链置换动力学。该方案通过调整各种环境刺激物的浓度，可在 2 个数量级范围内精细控制 DNA 链置换速率。该策略扩展了设计动态 DNA 器件的规则集，并将有助于构建各种环境刺激驱动的分子器件。
