{"paper_id":"2e6e23d2-c53c-4355-befe-647a3ec85f67","body_text":"Abstract\nMessenger RNA (mRNA) is a central polymer of gene expression, whose ultrastructure and defining regulatory rules remain unclear. To visualize the ultrastructure of mRNA, we here develop Combi-PAINT, a powerful and generalizable method for combinatorial super-resolved DNA-PAINT multiplexing, which we combine with high-efficiency RNA labelling and MINFLUX microscopy. This approach enables the nanometer-precision tracing of mRNA in three dimensions in cells. We use Combi-PAINT to visualize multiple distinct mRNA species inside the human cell nucleus and cytoplasm, revealing their quantitative ultrastructures and transcript-specific molecular patterns. By bridging sequence specificity with nanometer resolution, we provide a new lens for studying the cellular life of mRNA.\nCompeting Interest Statement\nFB holds patents on principles, embodiments and procedures of MINFLUX.","source_license":"CC-BY-4.0","license_restricted":false}