OTU (ovarian tumor) domain of plant deubiquitinating enzyme OTU9 and similar proteins
This subfamily contains Arabidopsis thaliana deubiquitinating enzymes OTU8, OTU9, OTU10, OTU11, and OTU12, and similar proteins from plants and other eukaryotes. OTU8-OTU12 are deubiquitinases (DUBs)/ubiquitin thiolesterases (EC 3.4.19.12) that catalyze the thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin, a small regulatory protein that can be conjugated to a large range of target proteins. Protein ubiquitination is a post-translational modification of mostly Lys residues that regulates many cellular processes, including protein degradation, intracellular trafficking, cell signaling, autophagy, transcription, translation, and the DNA damage response. These DUBs may play important regulatory roles at the level of protein turnover by preventing degradation. They belong to the OTU family of cysteine proteases that use a conserved cysteine, histidine, and an aspartate, as the catalytic triad.