Illuminating RNA through fluorescent light-up RNA aptamers

Visualizing RNA is critical for understanding RNA expression patterns and spatial organization within cells, offering valuable insights into gene regulation and cellular functions. High-resolution RNA imaging techniques are therefore indispensable for revealing the complexities of cellular pathways and physiological processes. Traditional RNA imaging methods, however, face significant limitations, such as high background noise resulting from labeling or cell fixation, which can impede the accurate tracking of RNA dynamics in live cells. Fluorescent light-up RNA aptamers (FLAPs) have emerged as a powerful alternative, distinguished by their capacity for enhanced fluorescence activation, reduced background interference, and advantages such as label-free imaging, small molecular size, and customizable structures. In this review, we provide an overview of the development of FLAPs, explore recent advancements in FLAP-based RNA imaging strategies, and discuss both the challenges and future directions in the field. Through this analysis, we aim to facilitate the further development and application of FLAPs in RNA research, fostering innovation and offering new perspectives in the study of RNA biology.