Hydrogen Sulfide-Triggered Artificial DNAzyme Switches for Precise Manipulation of Cellular Functions

The development of synthetic molecular tools responsive to biological cues is crucial for advancing targeted cellular regulation. A significant challenge is the regulation of cellular processes in response to gaseous signaling molecules such as hydrogen sulfide (H₂S). To address this, we present the design of Gas signaling molecule-Responsive Artificial DNAzyme-based Switches (GRAS) to manipulate cellular functions via H₂S-sensitive synthetic DNAzymes. By incorporating stimuli-responsive moieties to the phosphorothioate backbone, DNAzymes are strategically designed with H₂S-responsive azide groups at cofactor binding locations within the catalytic core region. These modifications enable their activation through H₂S-reducing decaging, thereby initiating substrate cleavage activity. Our approach allows for the flexible customization of various DNAzymes to regulate distinct cellular processes in diverse scenarios. Intracellularly, the enzymatic activity of GRAS promotes H₂S-induced cleavage of specific mRNA sequences, enabling targeted gene silencing and inducing apoptosis in cancer cells. Moreover, integrating GRAS with dynamic DNA assembly allows for grafting these functional switches onto cell surface receptors, facilitating H₂S-triggered receptor dimerization. This extracellular activation transmits signals intracellularly to regulate cellular behaviors such as migration and proliferation. Collectively, synthetic switches are capable of rewiring cellular functions in response to gaseous cues, offering a promising avenue for advanced targeted cellular engineering.