E3 ubiquitin ligase complex (E3 ligase)

The E3 ubiquitin ligase complex is a family of protein complexes that catalyze the transfer of ubiquitin from E2 ubiquitin-conjugating enzymes to specific substrate proteins, targeting them for proteasomal degradation or altering their cellular fate through post-translational modification. E3 ligases act as the substrate recognition component in the ubiquitination cascade, imparting specificity to the process. There are hundreds of distinct E3 ligase proteins encoded in the human genome, and they can function as single proteins (e.g., MDM2), multi-protein assemblies (e.g., SCF complex, anaphase-promoting complex), or members of large families (HECT, RING, U-box). The diversity of E3 ligases allows fine-tuned regulation of myriad biological processes, including cell cycle, apoptosis, DNA repair, immunity, protein trafficking, and adaptation to cellular stress. Dysregulation or mutation in E3 ligases is linked to a broad range of human diseases, most notably cancer and neurodegeneration. Pharmacological targeting of E3 ubiquitin ligase complexes is a promising and rapidly developing field in drug discovery and therapeutic intervention, exemplified by PROTAC technology and E3 ligase-specific inhibitors[1][3][4][5].

Other names

Ubiquitin ligaseE3 ligaseubiquitin–protein ligaseSCF complexanaphase-promoting complex (APC)cullin-RING ligase (CRL)HECT E3 ligase

Inducing targeted protein degradation; Inhibiting/subverting E3 ligase-substrate interactions; Modulating ubiquitination patterns to stabilize or degrade target proteins