Deubiquitinating enzyme involved in beta-2 adrenergic receptor (adrb2) recycling. Acts as a regulator of G-protein coupled receptor (GPCR) signaling by mediating the deubiquitination beta-2 adrenergic receptor (adrb2). Plays a central role in adrb2 recycling and resensitization after prolonged agonist stimulation by constitutively binding adrb2, mediating deubiquitination of adrb2 and inhibiting lysosomal trafficking of adrb2. Mediates deubiquitination of both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains (By similarity). Thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin (a 76-residue protein attached to proteins as an intracellular targeting signal). The UBP-type zinc finger binds 3 zinc ions. However, it does not bind ubiquitin, probably because the conserved Arg in position 55 is replaced by a Glu residue (By similarity). Belongs to the peptidase C19 family. USP20/USP33 subfamily.