Spatially and Single-Cell Resolved Profiling of RNA Life Cycle and Epitranscriptomics

The intricate network of cell functions relies on gene expression programs, where the whole RNA life cycle from DNA to protein is subjected to extensive transcriptional and post-transcriptional gene regulation events. Established bulk RNA sequencing methods provide an averaged, transcriptome-wide quantification of the RNA life cycle, including transcription, processing, translation, transport, and degradation through RNA-protein interactions. Furthermore, numerous studies using bulk epitranscriptomic profiling unveiled that dynamic RNA modifications (e. g., N⁶-Methyladenosine), add another layer of gene regulations. However, many regulatory events are cell-type specific, subcellularly localized, and subjected to cell-cell communications within the native tissue environment. Thanks to the advances in single-cell sequencing, spatial sequencing, and highly multiplexed imaging methods, we can routinely measure single-cell and spatial transcriptomics. Yet more comprehensive methods to profile every step of the RNA life cycle with single-cell and spatial information are still lacking. In this review, we will summarize and compare early explorations in developing state-of-the-art methods for spatially and single-cell resolved mapping of RNA kinetics, translation, RNA-protein interactions, and epitranscriptomics. It is promising that these new techniques will greatly facilitate our understanding of the RNA-centered regulation landscapes in different cell types and how the post-transcriptional regulations are interconnected within cellular and tissue architecture.