Expanding Biological Roles of Post-translational Arginylation

Protein arginylation is a conserved post-translational modification in eukaryotes, involving the conjugation of arginine residues to proteins by the enzyme arginyl-tRNA transferase. Historically associated with targeted degradation, recent studies have expanded this view by uncovering its broader regulatory influence across diverse cellular functions. This review first examines the established roles of arginylation in protein degradation through the Ubiquitin-Proteasome System and Autophagy-Lysosome System. It then highlights its non-degradative functions, including the modulation of protein-protein interactions, complex assembly, protein stability, and crosstalk with other post-translational modifications. Emerging evidence supports the notion that arginylation functions in a context dependent manner, simultaneously affecting both the stability and functional behaviour of proteins. Together, these works reveal arginylation as a dynamic and versatile mechanism that extends well beyond proteolysis, positioning it as a key global regulator of cellular functioning.