RESUMO
DNA nanowalkers moving progressively along a prescribed DNA track are useful tools in biosensing, molecular theranostics and biosynthesis. However, stochastic DNA nanowalkers that can perform in living cells have been largely unexplored. We report the development of a novel stochastic bipedal DNA walker that, for the first time, realizes direct intracellular base excision repair (BER) fluorescence activation imaging. In our design, the bipedal walker DNA was generated by BER-related human apurinic/apyrimidinic endonuclease 1 (APE1)-mediated cleavage of DNA sequences at an abasic site in the intracellular environment, and it autonomously travelled on spherical nucleic acid (SNA) surfaces via catalyzed hairpin assembly (CHA). Our nanomachine outperforms the conventional single leg-based DNA walker with an improved sensitivity, kinetics and walking steps. Moreover, in contrast to the single leg-based DNA walker, the bipedal DNA walker is capable of monitoring the fluorescence signal of reduced APE1 activity, thus indicating amplified intracellular imaging. This bipedal DNA-propelled DNA walker presents a simple and modular amplification mechanism for intracellular biomarkers of interest, providing an invaluable platform for low-abundance biomarker discovery leading to the accurate identification and effective treatment of cancers.
RESUMO
A well-defined 3D DNA nanostructure with precise composition was developed by stoichimetric combination of a DNA tetrahedron and Y-shaped DNA, which allowed multiplexed, signal-amplified fluorescence imaging of miRNAs in living cells via hybridization chain reaction.
Assuntos
Cor , DNA/química , MicroRNAs/análise , Nanoestruturas/química , Imagem Óptica , Sobrevivência Celular , MicroRNAs/genética , Hibridização de Ácido NucleicoRESUMO
A novel self-assembled protein-scaffolded CRISPR-Cas9 nanosystem for facile and efficient gene editing in a DNAzyme-controlled manner has been developed.
Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , DNA Catalítico/genética , Nanoestruturas/química , Biotina/química , Linhagem Celular Tumoral , Edição de Genes/métodos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Hibridização de Ácido Nucleico , RNA Guia de Cinetoplastídeos/genética , Estreptavidina/químicaRESUMO
A novel DNAzymatic amplifier nanomachine that is reconstructed in response to an mRNA input has been developed to enable the functions of concurrent sensitive mRNA imaging and activatable gene therapy in living cells.