5-Hydroxymethyluridine is primarily utilized in the field of biochemistry and molecular biology as a modified nucleoside. It plays a significant role in the study of RNA modifications and their impact on gene expression and RNA function. Researchers employ this compound to investigate the dynamics of RNA hydroxymethylation and its implications in cellular processes, including translation and RNA stability. Additionally, it is used in the synthesis of modified RNA molecules for therapeutic applications, such as mRNA vaccines, where it can enhance stability and reduce immunogenicity. Its incorporation into RNA sequences also aids in understanding the structural and functional roles of modified nucleosides in biological systems.