Mechanistic insights and methodological challenges in the study of glycosylated RNA: A review

Glycosylated RNA (GlycoRNA) constitutes a novel category of cell-surface nucleic acids characterized by intricate glycan modifications, thereby extending the scope of glycosylation beyond proteins and lipids and challenging the traditional notion that RNA is restricted to intracellular compartments. This review encapsulates recent advances in the field of GlycoRNA biology, including biochemical findings that 3-(3-amino-3-carboxypropyl) uridine to serve as an anchor covalent RNA-N-glycan conjugates. It also highlights advancements in methodologies such as metabolic labeling, spatial imaging, and transcriptome-wide mapping. Furthermore, we explore the emerging functional and translational implications of GlycoRNA in areas such as immune homeostasis, inflammatory cell chemotaxis, cancer therapy, and the discovery of biomarker for liquid biopsy. Nonetheless, recent evaluations have underscored significant technical limitations, particularly the nonspecific co-purification of glycoproteins during enrichment processes, which necessitate stringent orthogonal validation. This review synthesizes current evidence with outstanding questions concerning GlycoRNA biosynthesis, functional causality, and methodological specificity, proposing GlycoRNA as a conceptual advancement whose biological significance and translational potential are yet to be fully elucidated.