Small ubiquitin-like modifier 3 (SUMO3)

Small ubiquitin-like modifier 3 (SUMO3) is a member of the SUMO family of proteins that function as posttranslational modifiers in eukaryotic cells. SUMO3 is covalently conjugated to lysine residues on target proteins through an enzymatic cascade (involving E1, E2, and E3 enzymes), in a process called sumoylation. Unlike ubiquitin, which often tags proteins for degradation, SUMO3 modification typically alters protein localization, activity, stability, and interactions without triggering degradation. Biological roles of SUMO3 include regulating nuclear transport, DNA replication and repair, mitosis, transcriptional regulation, and stress responses. SUMO3 is highly similar to SUMO2 (sharing ~97% sequence identity) and these two are frequently studied together as “SUMO2/3.” Aberrant sumoylation involving SUMO3 is implicated in cancer, immune reactions, and cellular stress, but no currently approved drugs directly target SUMO3. SUMO pathway modulation is a subject of basic research and potential therapeutic investigation

Other names

Small ubiquitin-related modifier 3SMT3ASMT3H1SUMO-3Smt3ASmt3BSMT3 suppressor of mif two 3 homolog 1SMT3 suppressor of mif two 3 homolog 3Ubiquitin-like protein SMT3AUbiquitin-like protein SMT3Bsmall ubiquitin-like modifier 3SUMO2 (historical confusion/overlap in nomenclature, but SUMO2 and SUMO3 are encoded by distinct genes in humans)

Not applicable (SUMO3 modifies target proteins via *sumoylation*, a covalent and reversible posttranslational modification of lysine residues, but it is not directly drug-targeted)