Deciphering the Temporal-Spatial Interactive Heterogeneity of Long Non-Coding RNAs and RNA-Binding Proteins in Living Cells at Single-Cell Resolution.

The investigation of long noncoding RNAs (lncRNAs) and RNA binding proteins (RBPs) interactions in living cell holds great significance for elucidating their critical roles in a variety of biological activities, but limited techniques are available to profile the temporal-spatial dynamic heterogeneity. Here, we introduced a molecular beacon-functionalized nanoneedle array designed for spatially resolved profiling of lncRNA-RBP interactions (Nano-SpatiaLR). A nanoneedle array modified with a molecular beacon is employed to selectively isolate specific intracellular lncRNAs and their associated RBPs without affecting cell viability. The RBPs are then in situ analyzed with a fluorescent labeled antibody and colocalized with lncRNA signals to get a quantitative measurement of their dynamic interactions. Additionally, leveraging the spatial distribution and nanoscale modality of the nanoneedle array, this technique provides the spatial heterogeneity information on cellular lncRNA-RBPs interaction at single cell resolution. In this study, we tracked the temporal-spatial interactive heterogeneity dynamics of lncRNA-RBPs interaction within living cells across different biological progresses. Our findings demonstrated that the interactions between lncRNA HOTAIR and RBPs EZH2 and LSD1 undergo significant changes in response to drug treatments, particularly in tumor cells. Moreover, these interactions become more intensified as tumor cells aggregate during the proliferation process.