An Integrated Dual-Functional Nanotool Capable of Studying Single-Cell Epigenetics and Programmable Gene Regulation

Single-cell epigenetics is envisioned to decipher manifold epigenetic phenomena and to contribute to our accurate knowledge about basic epigenetic mechanisms. Engineered nanopipette technology has gained momentum in single-cell studies; however, solutions to epigenetic questions remain unachieved. This study addresses the challenge by exploring N6-methyladenine (m⁶ A)-bearing deoxyribozyme (DNAzyme) confined within a nanopipette for profiling a representative m⁶ A-modifying enzyme, fat mass and obesity-associated protein (FTO). Electroosmotic intracellular extraction of FTO could remove the m⁶ A and cause DNAzyme cleavage, leading to the altered ionic current signal. Because the cleavage can release a DNA sequence, we simultaneously program it as an antisense strand against FTO-mRNA, intracellular injection of which has been shown to induce early stage apoptosis. This nanotool thus features the dual functions of studying single-cell epigenetics and programmable gene regulation.