The Ubiquitin-specific Protease 12 (USP12) Is a Negative Regulator of Notch Signaling Acting on Notch Receptor Trafficking toward Degradation

Abstract NOTCH signaling is a method of cell-cell communication where membrane bound NOTCH ligands on signal-sending cells can bind to and initiate cleavage of the NOTCH receptor, releasing NICD which can initiate signal transduction in adjacent “signal-receiving” cells. We have recently shown that oHSV treatment of GBM cells induces NICD cleavage and NOTCH activation in adjacent uninfected glioma cells. RNA sequencing of GBM cells post-infection also uncovered Gene Ontology NOTCH signaling pathway to be significantly upregulated. This activation was induced by viral miRNA-H16, which represses FIH-1 expression. FIH-1 was found to be a negative regulator of Mib1, a ubiquitin ligase, which activates NOTCH ligand-mediated activation of adjacent signal-receiving cells bearing the NOTCH receptor (Otani et al Clin. Can. Res. 2020). Here we have investigated the impact of oHSV-induced NOTCH signaling on the tumor microenvironment. Treatment of brain tumors in immune competent mice with oHSV and NOTCH blocking gamma secretase inhibitor (GSI) induced an anti-tumor memory immune response. Long term survivors in mice treated with the combination also completely rejected subsequent tumor re-challenge in the other hemisphere. UMAP of flow cytometry of tumor-bearing hemispheres and functional analysis of isolated cellular fractions from treated mice showed a significant influx of MDSC cells after oHSV treatment that was rescued in mice treated with oHSV and GSI. Ongoing mechanistic studies are uncovering a significant induction of NOTCH in tumor associated macrophages that aids in recruitment of MDSC cells. Overall these studies have uncovered a significant impact of oHSV therapy on GBM tumor microenvironment and presents opportunities for combination therapies that can help improve therapeutic benefit and anti-tumor immunity.

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Ubiquitin-Specific Protease 4 Is an Endogenous Negative Regulator of Pathological Cardiac Hypertrophy

Hypertension ◽

10.1161/hypertensionaha.116.07392 ◽

2016 ◽

Vol 67 (6) ◽

pp. 1237-1248 ◽

Cited By ~ 20

Author(s):

Ben He ◽

Yi-Chao Zhao ◽

Ling-Chen Gao ◽

Xiao-Ying Ying ◽

Long-Wei Xu ◽

...

Keyword(s):

Cardiac Hypertrophy ◽

Negative Regulator ◽

Pathological Cardiac Hypertrophy ◽

Specific Protease ◽

Ubiquitin Specific Protease

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Roles of unphosphorylated ISGF3 in HCV infection and interferon responsiveness

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1513341112 ◽

2015 ◽

Vol 112 (33) ◽

pp. 10443-10448 ◽

Cited By ~ 42

Author(s):

Pil Soo Sung ◽

HyeonJoo Cheon ◽

Chung Hwan Cho ◽

Seon-Hui Hong ◽

Do Youn Park ◽

...

Keyword(s):

Transcription Factor ◽

Hcv Infection ◽

Negative Regulator ◽

Response Factor ◽

Specific Protease ◽

Infected Liver ◽

Chronic Hcv Infection ◽

Ubiquitin Specific Protease ◽

Chronic Activation ◽

Chronic Hcv

Up-regulation of IFN-stimulated genes (ISGs) is sustained in hepatitis C virus (HCV)-infected livers. Here, we investigated the mechanism of prolonged ISG expression and its role in IFN responsiveness during HCV infection in relation to unphosphorylated IFN-stimulated gene factor 3 (U-ISGF3), recently identified as a tripartite transcription factor formed by high levels of IFN response factor 9 (IRF9), STAT1, and STAT2 without tyrosine phosphorylation of the STATs. The level of U-ISGF3, but not tyrosine phosphorylated STAT1, is significantly elevated in response to IFN-λ and IFN-β during chronic HCV infection. U-ISGF3 prolongs the expression of a subset of ISGs and restricts HCV chronic replication. However, paradoxically, high levels of U-ISGF3 also confer unresponsiveness to IFN-α therapy. As a mechanism of U-ISGF3–induced resistance to IFN-α, we found that ISG15, a U-ISGF3-induced protein, sustains the abundance of ubiquitin-specific protease 18 (USP18), a negative regulator of IFN signaling. Our data demonstrate that U-ISGF3 induced by IFN-λs and -β drives prolonged expression of a set of ISGs, leading to chronic activation of innate responses and conferring a lack of response to IFN-α in HCV-infected liver.

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The Herpesvirus Associated Ubiquitin Specific Protease, USP7, Is a Negative Regulator of PML Proteins and PML Nuclear Bodies

PLoS ONE ◽

10.1371/journal.pone.0016598 ◽

2011 ◽

Vol 6 (1) ◽

pp. e16598 ◽

Cited By ~ 41

Author(s):

Feroz Sarkari ◽

Xueqi Wang ◽

Tin Nguyen ◽

Lori Frappier

Keyword(s):

Nuclear Bodies ◽

Negative Regulator ◽

Pml Nuclear Bodies ◽

Specific Protease ◽

Ubiquitin Specific Protease

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Ubiquitin-Specific Protease 4 Is an Endogenous Negative Regulator of Metabolic Dysfunctions in Nonalcoholic Fatty Liver Disease in Mice

Hepatology ◽

10.1002/hep.29889 ◽

2018 ◽

Vol 68 (3) ◽

pp. 897-917 ◽

Cited By ~ 12

Author(s):

Yichao Zhao ◽

Fang Wang ◽

Lingchen Gao ◽

Longwei Xu ◽

Renyang Tong ◽

...

Keyword(s):

Liver Disease ◽

Fatty Liver ◽

Nonalcoholic Fatty Liver Disease ◽

Fatty Liver Disease ◽

Negative Regulator ◽

Nonalcoholic Fatty Liver ◽

Specific Protease ◽

Ubiquitin Specific Protease ◽

Metabolic Dysfunctions

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The Drosophila melanogaster Suppressor of deltex Gene, a Regulator of the Notch Receptor Signaling Pathway, Is an E3 Class Ubiquitin Ligase

Genetics ◽

10.1093/genetics/152.2.567 ◽

1999 ◽

Vol 152 (2) ◽

pp. 567-576 ◽

Cited By ~ 13

Author(s):

M Cornell ◽

D A P Evans ◽

R Mann ◽

M Fostier ◽

M Flasza ◽

...

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Cell Fate ◽

Ubiquitin Ligase ◽

Notch Pathway ◽

Notch Receptor ◽

Negative Regulator ◽

Loss Of Function ◽

Wing Vein ◽

Cell Fate Decisions

Abstract During development, the Notch receptor regulates many cell fate decisions by a signaling pathway that has been conserved during evolution. One positive regulator of Notch is Deltex, a cytoplasmic, zinc finger domain protein, which binds to the intracellular domain of Notch. Phenotypes resulting from mutations in deltex resemble loss-of-function Notch phenotypes and are suppressed by the mutation Suppressor of deltex [Su(dx)]. Homozygous Su(dx) mutations result in wing-vein phenotypes and interact genetically with Notch pathway genes. We have previously defined Su(dx) genetically as a negative regulator of Notch signaling. Here we present the molecular identification of the Su(dx) gene product. Su(dx) belongs to a family of E3 ubiquitin ligase proteins containing membrane-targeting C2 domains and WW domains that mediate protein-protein interactions through recognition of proline-rich peptide sequences. We have identified a seven-codon deletion in a Su(dx) mutant allele and we show that expression of Su(dx) cDNA rescues Su(dx) mutant phenotypes. Overexpression of Su(dx) also results in ectopic vein differentiation, wing margin loss, and wing growth phenotypes and enhances the phenotypes of loss-of-function mutations in Notch, evidence that supports the conclusion that Su(dx) has a role in the downregulation of Notch signaling.

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Ubiquitin-specific protease 4 (USP4) targets TRAF2 and TRAF6 for deubiquitination and inhibits TNFα-induced cancer cell migration

Biochemical Journal ◽

10.1042/bj20111358 ◽

2012 ◽

Vol 441 (3) ◽

pp. 979-987 ◽

Cited By ~ 91

Author(s):

Ning Xiao ◽

Hui Li ◽

Jian Luo ◽

Rui Wang ◽

Haiquan Chen ◽

...

Keyword(s):

Cell Migration ◽

Cancer Cell ◽

Signalling Pathway ◽

Negative Regulator ◽

Dependent Manner ◽

Cancer Cell Migration ◽

Specific Protease ◽

Ubiquitin Specific Protease

TRAF [TNF (tumour necrosis factor)-receptor-associated factor] 2 and 6 are essential adaptor proteins for the NF-κB (nuclear factor κB) signalling pathway, which play important roles in inflammation and immune response. Polyubiquitination of TRAF2 and TRAF6 is critical to their activities and functions in TNFα- and IL (interleukin)-1β-induced NF-κB activation. However, the regulation of TRAF2 and TRAF6 by deubiquitination remains incompletely understood. In the present study, we identified USP (ubiquitin-specific protease) 4 as a novel deubiquitinase targeting TRAF2 and TRAF6 for deubiquitination. We found that USP4 specifically interacts with TRAF2 and TRAF6, but not TRAF3. Moreover, USP4 associates with TRAF6 both in vitro and in vivo, independent of its deubiquitinase activity. The USP domain is responsible for USP4 to interact with TRAF6. Ectopic expression of USP4 inhibits the TRAF2- and TRAF6-stimulated NF-κB reporter gene and negatively regulates the TNFα-induced IκBα (inhibitor of NF-κBα) degradation and NF-κB activation. Knockdown of USP4 significantly increased TNFα-induced cytokine expression. Furthermore, we found that USP4 deubiquitinates both TRAF2 and TRAF6 in vivo and in vitro in a deubiquitinase activity-dependent manner. Importantly, the results of the present study showed that USP4 is a negative regulator of TNFα- and IL-1β-induced cancer cell migration. Taken together, the present study provides a novel insight into the regulation of the NF-κB signalling pathway and uncovers a previously unknown function of USP4 in cancer.

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Genetic Characterization of the Drosophila melanogaster Suppressor of deltex Gene: A Regulator of Notch Signaling

Genetics ◽

10.1093/genetics/150.4.1477 ◽

1998 ◽

Vol 150 (4) ◽

pp. 1477-1485

Author(s):

Maggy Fostier ◽

Dana A P Evans ◽

Spyros Artavanis-Tsakonas ◽

Martin Baron

Keyword(s):

Notch Signaling ◽

Notch Pathway ◽

Notch Receptor ◽

Negative Regulator ◽

Loss Of Function ◽

Wing Vein ◽

Notch Protein ◽

Receptor Signaling Pathway ◽

Multicellular Organisms ◽

Notch Receptor Signaling

Abstract The Notch receptor signaling pathway regulates cell differentiation during the development of multicellular organisms. A number of genes are known to be components of the pathway or regulators of the Notch signal. One candidate for a modifier of Notch function is the Drosophila Suppressor of deltex gene [Su(dx)]. We have isolated four new alleles of Su(dx) and mapped the gene between 22B4 and 22C2. Loss-of-function Su(dx) mutations were found to suppress phenotypes resulting from loss-of-function of Notch signaling and to enhance gain-of-function Notch mutations. Hairless, a mutation in a known negative regulator of the Notch pathway, was also enhanced by Su(dx). Phenotypes were identified for Su(dx) in wing vein development, and a role was demonstrated for the gene between 20 and 30 hr after puparium formation. This corresponds to the period when the Notch protein is involved in refining the vein competent territories. Taken together, our data indicate a role for Su(dx) as a negative regulator of Notch function.

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Ehrlichia SLiM ligand mimetic activates Notch signaling in human monocytes

10.1101/2022.01.13.476283 ◽

2022 ◽

Author(s):

LaNisha L. Patterson ◽

Thangam Sudha Velayutham ◽

Caitlan D. Byerly ◽

Duc Cuong Bui ◽

Jignesh Patel ◽

...

Keyword(s):

Notch Signaling ◽

Tandem Repeat ◽

Nuclear Translocation ◽

Peptide Mapping ◽

Notch Receptor ◽

Negative Regulator ◽

Receptor Interaction ◽

Linear Motif ◽

Notch Ligands ◽

Notch Activation

Ehrlichia chaffeensis evades innate host defenses by reprogramming the mononuclear phagocyte through mechanisms that involve exploitation of multiple evolutionarily conserved cellular signaling pathways including Notch. This immune evasion strategy is directed in part by tandem repeat protein (TRP) effectors. Specifically, the TRP120 effector activates and regulates Notch signaling through interactions with the Notch receptor and the negative regulator, F-Box and WD repeat domain-containing 7 (FBW7). However, the specific molecular interactions and motifs required for E. chaffeensis TRP120-Notch receptor interaction and activation have not been defined. To investigate the molecular basis of TRP120 Notch activation, we compared TRP120 with endogenous canonical/non-canonical Notch ligands and identified a short region of sequence homology within the tandem repeat (TR) domain. TRP120 was predicted to share biological function with Notch ligands, and a function-associated sequence in the TR domain was identified. To investigate TRP120-Notch receptor interactions, colocalization between TRP120 and endogenous Notch-1 was observed. Moreover, direct interactions between full length TRP120, the TRP120 TR domain containing the putative Notch ligand sequence, and the Notch receptor LBR were demonstrated. To molecularly define the TRP120 Notch activation motif, peptide mapping was used to identify an 11-amino acid short linear motif (SLiM) located within the TRP120 TR that activated Notch signaling and downstream gene expression. Peptide mutants of the Notch SLiM or anti-Notch SLiM antibody reduced or eliminated Notch activation and NICD nuclear translocation. This investigation reveals a novel molecularly defined pathogen encoded Notch SLiM mimetic that activates Notch signaling consistent with endogenous ligands.

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