| Autor: |
Ying ZM; Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China., Wu Z; Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China., Tu B; Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China., Tan W; Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China., Jiang JH; Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China. |
| Abstrakt: |
Light-up RNA aptamers are valuable tools for fluorescence imaging of RNA in living cells and thus for elucidating RNA functions and dynamics. However, no light-up RNA sensor has been reported for imaging of microRNAs (miRs) in mammalian cells. We report a novel genetically encoded RNA sensor for fluorescent imaging of miRs in living tumor cells using a light-up RNA aptamer that binds to sulforhodamine and separates it from a conjugated contact quencher. On the basis of the structural switching mechanism for molecular beacon, we show that the RNA sensor activates high-contrast fluorescence from the sulforhodamine-quencher conjugate when its stem-loop responsive motif hybridizes with target miR. The RNA sensor can be stably expressed within a designed tRNA scaffold in tumor cells and deliver light-up response to miR target. We also realize the RNA sensor for dual-emission, ratiometric imaging by coexpression of RNA sensor with GFP, enabling quantitative studies of target miR in living cells. Our design may provide a new paradigm for developing robust, sensitive light-up RNA sensors for RNA imaging applications. |
