When a ribosome complex is stalled during the translation elongation process in eukaryotes, the mono-ubiquitination of Rps3 has recently been shown to be critical to ribosome quality control. We have discovered that the regulatory role of Rps3 mono-ubiquitination is controlled by a deubiquitinase. We also showed that an autophagic signal appears to be coupled to the mono-ubiquitination of Rps3p through the entrance of Ubp3p into the autophagosome in yeasts. The mono-ubiquitination of the Rps3 protein is tightly modulated by reciprocal action between the Hel2p E3 ligase and the Ubp3p deubiquitinase in yeasts and the reciprocal action between the RNF123 E3 ligase and the USP10 deubiquitinase in mammalian cells. We also found that the Ubp3p/USP10 deubiquitinases critically modulate Hel2p/RNF123-mediated Rps3p mono-ubiquitination. In addition, we found that Hel2p/RNF123 and Ubp3p/USP10 appeared to be differently localized in the ribosome complex after ultraviolet irradiation. Together, our results support a model in which coordinated ubiquitination and deubiquitination activities can finely balance the level of regulatory Rps3p mono-ubiquitination in ribosome-associated quality control and autophagy processes.
Autophagy ; Eukaryota ; Quality Control* ; Ribosomes ; Ubiquitin ; Ubiquitin-Protein Ligases* ; Ubiquitin-Specific Proteases ; Ubiquitination ; Yeasts

As the major pathway mediating specific protein degradation in eukaryotes, ubiquitin-proteasome system (UPS) is involved in various physiological and pathological processes such as cell cycle regulation, immune response, signal transduction and DNA-repair. Deubiquitinases (DUB) maintain the balance of UPS and related physiological processes via reversibly removing ubiquitin from the covalently modified protein substrates, which have been implicated in various disease processes in case of their imbalance expression. Because DUB plays critical regulating roles in the UPS pathway, they may be also the ideal drug targets for severe and intractable human diseases, such as cancer and neurodegenerative disease. With the rapid development of proteomic technology, systematical investigation of specific substrates and interacting proteins of varied DUB via mass spectrometry approach may shed light on these DUB's biological function and regulating roles in the physiological and pathogenic states. In this review, we briefly introduce the characteristics of DUB and summarize the recent application and progresses of proteomics in DUB research.
Humans ; Mass Spectrometry ; Proteasome Endopeptidase Complex ; metabolism ; Proteomics ; Signal Transduction ; Ubiquitin ; metabolism ; Ubiquitin-Specific Proteases ; metabolism

Ubiquitin-specific protease(USP), which belongs to cysteine protease, is an important member of the deubiquitinating enzyme family(DUB). USP plays an important role in the immune response against viral infections, in which it can regulate the production of type I interferon through various ways to initiate or weaken the antiviral immune response. USP2b, USP3, USP18, USP25, UL36USP and HAUSP play a role of antivirus; while USP4, USP13, USP15 and USP17 negatively regulate antiviral immune response. In this article we review the recent progress on roles of USP family in antiviral immune response.
Humans ; Interferon Type I ; immunology ; Ubiquitin-Specific Proteases ; immunology ; Virus Diseases ; immunology

Apoptosis ; Autophagy ; Ferroptosis ; Iron/metabolism* ; Sequestosome-1 Protein/metabolism* ; Ubiquitin-Specific Proteases/metabolism*

Ubiquitination of proteins plays an essential role in various cellular processes, including protein degradation, DNA repair, and cell signaling pathways. Previous studies have shown that protein ubiquitination is implicated in regulating pluripotency as well as fate determination of stem cells. To identify how protein ubiquitination affects differentiation of embryonic stem cells, we analyzed microarray data, which are available in the public domain, of E3 ligases and deubiquitinases whose levels changed during stem cell differentiation. Expression of pja2, a member of the RING-type E3 ligase family, was up-regulated during differentiation of stem cells. Wnt/β-catenin signaling is one of the most important signaling pathways for regulation of the self-renewal and differentiation of embryonic stem cells. Pja2 was shown to bind to TCF/LEF1, which are transcriptional factors for Wnt/β-catenin signaling, and regulate protein levels by ubiquitination, leading to down-regulation of Wnt signaling activity. Based on these results, we suggest that E3 ligase Pja2 regulates stem cell differentiation by controlling the level of TCF/LEF1 by ubiquitination.
DNA Repair ; Down-Regulation ; Embryonic Stem Cells ; Humans ; Ligases ; Proteolysis ; Public Sector ; Stem Cells ; Ubiquitin ; Ubiquitin-Protein Ligases ; Ubiquitin-Specific Proteases ; Ubiquitination

OBJECTIVE: To study the expression and significance of ubiquitin-specific protease 7 (USP7) and the key factors of the Wnt signaling pathway in the lung tissue of preterm rats after hyperoxia exposure. METHODS: A total of 180 preterm neonatal Wistar rats were randomly divided into an air control group, an air intervention group, a hyperoxia control group, and a hyperoxia intervention group, with 45 rats in each group. Lung injury was induced by hyperoxia exposure in the hyperoxia groups. The preterm rats in the intervention groups were given intraperitoneal injection of the USP7 specific inhibitor P5091 (5 mg/kg) every day. The animals were sacrificed on days 3, 5, and 9 of the experiment to collect lung tissue specimens. Hematoxylin-eosin staining was used to observe the pathological changes of lung tissue. RT-PCR and Western blot were used to measure the mRNA and protein expression levels of USP7 and the key factors of the Wnt signaling pathway β-catenin and α-smooth muscle actin (α-SMA) in lung tissue. RESULTS: The air groups had normal morphology and structure of lung tissue; on days 3 and 5, the hyperoxia control group showed obvious alveolar compression and disordered structure, with obvious inflammatory cells, erythrocyte diapedesis, and interstitial edema. On day 9, the hyperoxia control group showed alveolar structural disorder and obvious thickening of the alveolar septa. Compared with the hyperoxia control group at the corresponding time points, the hyperoxia intervention group had significantly alleviated disordered structure, inflammatory cell infiltration, and bleeding in lung tissue. At each time point, the hyperoxia groups had a significantly lower radial alveolar count (RAC) than the corresponding air groups ( CONCLUSIONS Hyperoxia exposure can activate the Wnt/β-catenin signaling pathway, and USP7 may participate in hyperoxic lung injury through the Wnt/β-catenin signaling pathway. The USP7 specific inhibitor P5091 may accelerate the degradation of β-catenin by enhancing its ubiquitination, reduce lung epithelial-mesenchymal transition, and thus exert a certain protective effect against hyperoxic lung injury.
Animals ; Animals, Newborn ; Hyperoxia/physiopathology* ; Lung/physiopathology* ; Random Allocation ; Rats ; Rats, Wistar ; Thiophenes/pharmacology* ; Ubiquitin-Specific Peptidase 7/metabolism* ; Ubiquitin-Specific Proteases ; Wnt Signaling Pathway

Transforming growth factor-β (TGF-β) members are key cytokines that control embryogenesis and tissue homeostasis via transmembrane TGF-β type II (TβR II) and type I (TβRI) and serine/threonine kinases receptors. Aberrant activation of TGF-β signaling leads to diseases, including cancer. In advanced cancer, the TGF-β/SMAD pathway can act as an oncogenic factor driving tumor cell invasion and metastasis, and thus is considered to be a therapeutic target. The activity of TGF-β/SMAD pathway is known to be regulated by ubiquitination at multiple levels. As ubiquitination is reversible, emerging studies have uncovered key roles for ubiquitin-removals on TGF-β signaling components by deubiquitinating enzymes (DUBs). In this paper, we summarize the latest findings on the DUBs that control the activity of the TGF-β signaling pathway. The regulatory roles of these DUBs as a driving force for cancer progression as well as their underlying working mechanisms are also discussed.
Animals ; Humans ; Molecular Targeted Therapy ; Receptors, Transforming Growth Factor beta ; metabolism ; Signal Transduction ; Smad Proteins ; physiology ; Transforming Growth Factor beta ; physiology ; Ubiquitin Thiolesterase ; metabolism ; Ubiquitin-Specific Proteases ; Ubiquitination

Objective To investigate the expression of long non-coding RNA ubiquitin-specific peptidase 30 antisense RNA 1 (lncRNA USP30-AS1) and its relationship with immune infiltration in ovarian serous cystadenocarcinoma (OSC), and to determine its prognostic role in OSC. Methods The Cancer Genome Atlas (TCGA) database was utilized to retrieve the expression of USP30-AS1 and clinical information of 384 OSC patients. Wilcoxon rank-sum test was employed to compare the expression of USP30-AS1 between OSC and normal ovarian tissues. Logistic regression analysis was conducted to assess the relationship between clinical pathological features and USP30-AS1. Gene set enrichment analysis (GSEA) and single-sample gene set enrichment analysis (ssGSEA) were performed to investigate enrichment pathways and functions and quantify the degree of immune cell infiltration in USP30-AS1. Based on the expression level of long non-coding RNA (lncRNA) USP30-AS1, the samples were divided into high and low expression groups according to the expression mean. Log-rank tests, univariate and multivariate proportional hazards model (Cox) were used to compare prognostic differences between different USP30-AS1 expression groups. The impact of lncRNA USP30-AS1 expression on other genomic analyses was also analyzed. Results High expression of USP30-AS1 was significantly associated with the International Federation of Gynecology and Obstetrics (FIGO) stage of the tumor. Multivariate survival analysis indicated that USP30-AS1 expression level served as an independent prognostic marker for OSC. GSEA data showed that high expression of USP30-AS1 might activate programmed death 1 (PD-1) signaling pathway, cytotoxic T lymphocyte-associated protein 4 (CTLA4) pathway, B-cell receptor signaling pathway, cell apoptosis, fibroblast growth factor receptor (FGFR) signaling pathway, and Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway. The expression of USP30-AS1 was negatively correlated with immune cell infiltration, including B cells, CD4⁺ T cells, dendritic cells, CD8⁺ T cells, and neutrophils. Conclusion USP30-AS1 may be used as a prognostic molecular marker for OSC.
Female ; Humans ; Pregnancy ; CD8-Positive T-Lymphocytes ; Computational Biology ; Cystadenocarcinoma, Serous/genetics* ; RNA, Antisense ; RNA, Long Noncoding/genetics* ; Ubiquitin-Specific Proteases/genetics*

The deubiquitinating enzyme ubiquitin specific peptidase 15 (USP15) is regarded as a regulator of TGFβ signaling pathway. This process depends on Smad7, the inhibitory factor of the TGFβ signal, and type I TGFβ receptor (TβR-I), one of the receptors of TGFβ. The expression level of USP15 seems to play vital roles in the pathogenesis of many neoplasms, but so far there has been no report about USP15 in psoriasis. In this study, immunohistochemical staining of USP15, TβR-I and Smad7 was performed in 30 paraffin-embedded psoriasis specimens and 10 normal specimens to investigate the expression of USP15, TβR-I and Smad7 in psoriasis and to explore the relevance among them. And USP15 small interfering RNA (USP15 siRNA) was used to transfect Hacat cells to detect the mRNA expression of TβR-I and Smad7. Of 30 cases of psoriasis in active stage, 28, 24 and 26 cases were positive for USP15, TβR-I and Smad7 staining, respectively. The positive rates of USP15 and Smad7 were significantly higher in psoriasis specimens than in normal skin specimens (44.1%±26.0% vs. 6.1%±6.6%, 47.2%±27.1% vs. 6.6%±7.1%), and positive rate of TβR-I (20.3%±22.2%) in psoriasis was lower than that in normal skin specimens (46.7%±18.2%). There was a significant positive correlation between USP15 and Smad7 expression, and significant negative correlations between USP15 and TβR-expression, an I d between TβR- and Smad7 expression I in psoriasis. After transfection of USP15 siRNA in Hacat cells, the expression of TβR-mRNA was up I -regulated and that of Smad7 was down-regulated. It is concluded that USP15 may play a role in the pathogenesis of psoriasis through regulating the TβR-I/Smad7 pathway and there may be other cell signaling pathways interacting with USP15 to take part in the development of psoriasis.
Adult ; Cell Line ; Female ; Gene Expression ; Humans ; Immunohistochemistry ; Keratinocytes ; cytology ; metabolism ; Male ; Middle Aged ; Protein-Serine-Threonine Kinases ; biosynthesis ; genetics ; Psoriasis ; genetics ; metabolism ; RNA Interference ; Receptors, Transforming Growth Factor beta ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; genetics ; Skin ; metabolism ; Smad7 Protein ; biosynthesis ; genetics ; Ubiquitin-Specific Proteases ; biosynthesis ; genetics ; Young Adult

AIMTo study the incidence of single nucleotide polymorphisms in ubiquitin-specific protease 26 (USP26) gene and its involvement in idiopathic male infertility in China.

METHODSRoutine semen analysis was performed. Infertility factors such as immunological, infectious and biochemical disorders were examined to select patients with idiopathic infertility. DNA was isolated from peripheral blood of the selected patients and control population, which were examined for mutations using polymerase chain reaction-single strand conformation polymorphism analysis. Furthermore, nucleotide sequences were sequenced in some patients and controls.

RESULTSOf 41 infertile men, 9 (22.0%, P = 0.01) had changes in USP26 gene on the X chromosome. A compound mutation (364insACA; 460G right triple arrow A) was detected in 8 patients (19.5%, P = 0.01) and a 1044T right triple arrow A substitution was found in 1 patient (2.4%, P > 0.05). All three variations led to changes in the coding amino acids. Two substitutions predict some changes: 460G right triple arrow A changes a valine into an isoleucine, and 1044T right triple arrow A substitutes a leucine for a phenylalanine. Another insertion of three nucleotides ACA causes an insertion of threonine. No other changes were found in the remaining patients and fertile controls.

CONCLUSIONThe USP26 gene might be of importance in male reproduction. Mutations in this gene might be associated with male infertility, and might negatively affect testicular function. Further research on this issue is in progress.

Asian Continental Ancestry Group ; ethnology ; genetics ; Case-Control Studies ; China ; Cysteine Endopeptidases ; genetics ; metabolism ; Endopeptidases ; genetics ; metabolism ; Humans ; Incidence ; Infertility, Male ; ethnology ; genetics ; Leydig Cells ; metabolism ; Male ; Polymorphism, Single Nucleotide ; genetics ; RNA, Messenger ; genetics ; metabolism ; Sertoli Cells ; metabolism ; Spermatogenesis ; genetics ; Testis ; metabolism ; Ubiquitin-Specific Proteases