E3 Ubiquitin-Protein Ligase (E3)

E3 ubiquitin-protein ligases are a diverse family of enzymes responsible for substrate specificity in the ubiquitination process. They facilitate the attachment of ubiquitin to target proteins, regulating protein degradation, cellular localization, protein interactions, and stability. Dysregulation of E3 ligases is implicated in various diseases, making them potential drug targets.

Catalyzes the transfer of ubiquitin from an E2 ubiquitin-conjugating enzyme to substrate proteins, marking them for degradation or altering their function/location. Different E3 ligases (RING, HECT, RBR, Cullin-RING) employ distinct mechanisms to achieve this.