The function of OTUD3 (OTU deubiquitinase 3, Ensembl gene identifier ENSG00000169914) is as follows. Deubiquitinating enzyme that hydrolyzes 'Lys-6'- and 'Lys- 11'-linked polyubiquitin. Also hydrolyzes heterotypic (mixed and branched) and homotypic chains (PubMed:23827681, PubMed:32011234, PubMed:35675826). Important regulator of energy metabolism (PubMed:35675826). Glucose and fatty acids trigger its nuclear translocation by CBP-dependent acetylation (PubMed:35675826). In the nucleus, deubiquitinates and stabilizes the nuclear receptor PPARD regulating the expression of various genes involved in glucose and lipid metabolism and oxidative phosphorylation (PubMed:35675826). Also acts as a negative regulator of the ribosome quality control (RQC) by mediating deubiquitination of 40S ribosomal proteins RPS10/eS10 and RPS20/uS10, thereby antagonizing ZNF598-mediated 40S ubiquitination (PubMed:32011234). {ECO:0000269|PubMed:23827681, ECO:0000269|PubMed:32011234, ECO:0000269|PubMed:35675826}.