USP4

Deubiquitinating enzyme that removes conjugated ubiquitin from target proteins. Deubiquitinates PDPK1. Deubiquitinates TRIM21. Deubiquitinates receptor ADORA2A which increases the amount of functional receptor at the cell surface. Deubiquitinates HAS2. Deubiquitinates MAVs leading to maintain MAVS protein stability, resulting in increased production of type I interferons (IFN-I) and enhanced antiviral innate immune responses against viral infections. Deubiquitinates RHEB in response to EGF signaling, promoting mTORC1 signaling. May regulate mRNA splicing through deubiquitination of the U4 spliceosomal protein PRPF3. This may prevent its recognition by the U5 component PRPF8 thereby destabilizing interactions within the U4/U6.U5 snRNP. May also play a role in the regulation of quality control in the ER..

Function from UniProtKB (Q13107), read 2026-09-23. CC BY 4.0.