OTU (ovarian tumor) domain of OTU domain-containing protein 3 and similar proteins
This subfamily includes bilaterial OTU domain-containing protein 3 (OTUD3), Arabidopsis thaliana deubiquitinating enzyme OTU7, also called OTU domain-containing protein 7, and similar proteins. OTUD3 is a deubiquitinase (DUB)/ubiquitin thioesterase (EC 3.4.19.12) that hydrolyzes 'Lys-6'- and 'Lys-11'-linked polyubiquitin. It is an acetylation-dependent deubiquitinase that restricts innate antiviral immune signaling. It directly hydrolyzes lysine 63 (Lys63)-linked polyubiquitination of MAVS (mitochondrial antiviral-signaling protein) and shuts off innate antiviral immune response. OTUD3 can elicit tumor-suppressing or tumor-promoting activities in a cell- and tissue-dependent manner. It is a DUB for PTEN (phosphatase and tension homologue deleted on chromosome 10); the OTUD3-PTEN signaling axis plays a critical role in suppression of breast tumorigenesis. OTUD3 is also a DUB for glucose-regulated protein GRP78, stabilizing it and promoting lung tumorigenesis. OTU7 is a DUB that shows a preference for 'Lys-63' over 'Lys-48' over 'Met-1'-linked ubiquitin (UB) tetramers as substrates. This subfamily belongs to the OTU family of cysteine proteases that use a conserved cysteine, histidine, and an aspartate, as the catalytic triad.
Jiyao W et al.(2023). "The conserved domain database in 2023.",