Arginylation branch of the N-end rule pathway (Arg/N-end rule pathway)

The Arginylation branch of the N-end rule pathway (Arg/N-end rule pathway) is a eukaryotic protein quality control and degradation system where the identity and modification state of the protein's N-terminal amino acid determines its ubiquitin-dependent proteasomal degradation rate. In this pathway, after proteolytic cleavage exposes specific N-terminal residues (such as Asp, Glu, oxidized Cys), the enzyme arginyltransferase (ATE1) may add an arginine, creating an N-degron recognized by E3 ubiquitin ligases (notably the UBR family). This marks the protein for polyubiquitination and subsequent degradation by the proteasome. The pathway regulates numerous cellular functions, including cell cycle, apoptosis, developmental processes, oxygen sensing, and response to stress, and is implicated in diseases including neurodegeneration, cardiovascular disorders, and rare genetic conditions. Importantly, Arg/N-end rule pathway is a cellular process/system, NOT a single druggable protein or receptor. Direct drug targeting typically focuses on specific enzymes within this route (for example, ATE1 or UBR ligases), not the pathway as a whole.

Other names

Arginylation-dependent N-end rule pathwayArginylation branch of the N-end ruleN-terminal arginylation pathwayArg/N-degron pathway

Not applicable for the pathway as a whole. For component targeting (e.g., ATE1 or UBR E3 ligases): mechanisms include inhibition/activation of ubiquitin ligase or arginyltransferase activity, or modulation of N-terminal residue recognition.