4wpi
Crystal structure of USP7 ubiquitin-like domains in extended conformationCrystal structure of USP7 ubiquitin-like domains in extended conformation
Structural highlights
FunctionUBP7_HUMAN Hydrolase that deubiquitinates target proteins such as FOXO4, p53/TP53, MDM2, ERCC6, DNMT1, UHRF1, PTEN and DAXX. Together with DAXX, prevents MDM2 self-ubiquitination and enhances the E3 ligase activity of MDM2 towards p53/TP53, thereby promoting p53/TP53 ubiquitination and proteasomal degradation. Deubiquitinates p53/TP53 and MDM2 and strongly stabilizes p53/TP53 even in the presence of excess MDM2, and also induces p53/TP53-dependent cell growth repression and apoptosis. Deubiquitination of FOXO4 in presence of hydrogen peroxide is not dependent on p53/TP53 and inhibits FOXO4-induced transcriptional activity. In association with DAXX, is involved in the deubiquitination and translocation of PTEN from the nucleus to the cytoplasm, both processes that are counteracted by PML. Involved in cell proliferation during early embryonic development. Involved in transcription-coupled nucleotide excision repair (TC-NER) in response to UV damage: recruited to DNA damage sites following interaction with KIAA1530/UVSSA and promotes deubiquitination of ERCC6, preventing UV-induced degradation of ERCC6. Contributes to the overall stabilization and trans-activation capability of the herpesvirus 1 trans-acting transcriptional protein ICP0/VMW110 during HSV-1 infection. Involved in maintenance of DNA methylation via its interaction with UHRF1 and DNMT1: acts by mediating deubiquitination of UHRF1 and DNMT1, preventing their degradation and promoting DNA methylation by DNMT1. Exhibits a preference towards 'Lys-48'-linked Ubiquitin chains.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] Publication Abstract from PubMedHerpes simplex virus-1 immediate-early protein ICP0 activates viral genes during early stages of infection, affects cellular levels of multiple host proteins and is crucial for effective lytic infection. Being a RING-type E3 ligase prone to auto-ubiquitination, ICP0 relies on human deubiquitinating enzyme USP7 for protection against 26S proteasomal mediated degradation. USP7 is involved in apoptosis, epigenetics, cell proliferation and is targeted by several herpesviruses. Several USP7 partners, including ICP0, GMPS, and UHRF1, interact through its C-terminal domain (CTD), which contains five ubiquitin-like (Ubl) structures. Despite the fact that USP7 has emerged as a drug target for cancer therapy, structural details of USP7 regulation and the molecular mechanism of interaction at its CTD have remained elusive. Here, we mapped the binding site between an ICP0 peptide and USP7 and determined the crystal structure of the first three Ubl domains bound to the ICP0 peptide, which showed that ICP0 binds to a loop on Ubl2. Sequences similar to the USP7-binding site in ICP0 were identified in GMPS and UHRF1 and shown to bind USP7-CTD through Ubl2. In addition, co-immunoprecipitation assays in human cells comparing binding to USP7 with and without a Ubl2 mutation, confirmed the importance of the Ubl2 binding pocket for binding ICP0, GMPS and UHRF1. Therefore we have identified a novel mechanism of USP7 recognition that is used by both viral and cellular proteins. Our structural information was used to generate a model of near full-length USP7, showing the relative position of the ICP0/GMPS/UHRF1 binding pocket and the structural basis by which it could regulate enzymatic activity. Crystal Structure of USP7 Ubiquitin-like Domains with an ICP0 Peptide Reveals a Novel Mechanism Used by Viral and Cellular Proteins to Target USP7.,Pfoh R, Lacdao IK, Georges AA, Capar A, Zheng H, Frappier L, Saridakis V PLoS Pathog. 2015 Jun 5;11(6):e1004950. doi: 10.1371/journal.ppat.1004950., eCollection 2015 Jun. PMID:26046769[14] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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