The Dependency Map (DepMap) is a genome-wide pooled
CRISPR-Cas9 knockout proliferation screen conducted in more than 700 cancer cell lines spanning many
different tumor lineages. Each cell line in the DepMap contains a unique barcode, and each gene
knockout is assigned a “dependency score” on a per cell-line basis which quantifies the rate of
CRISPR-Cas9 guide drop. It has been found that proteins with similar DepMap scores across cell
lines, a phenomenon known as co-dependent genes, have closely related biological functions. This can
include activity in the same or parallel pathways or membership in the same protein complex or the
same pathway.
We identified the strongest seven co-dependent genes (“Symbol”) for DUBs and ran GO enrichment
analysis. We used Biogrid, IntAct, and Pathway Commons PPIDs, and the NURSA protein-protein
interaction databases (PPIDs) to determine whether co-dependent genes interact with one another. The
“Evidence” column contains the PPIDs in which the interaction appears as well as whether there is
support for the association by an INDRA statement. As another approach to identify potential
interactors, we looked at proteomics data from the Broad Institute's Cancer Cell Line Encyclopedia (CCLE) for
proteins whose expression across ~375 cell lines strongly correlated with the abundance of each DUB;
it has previously been observed that proteins in the same complex are frequently significantly
co-expressed. The correlations and associated p-values in the CCLE proteomics dataset are provided.
And, we determined whether co-dependent genes yield similar transcriptomic signatures
in the Broad Institute's Connectivity
Map (CMap). A CMap score greater than 90 is considered significantly similar.
Using the biological processes and other Gene Ontology terms from well characterized DUBs as a
positive control, several gene set enrichment analyses were considered. Threshold-less methods
like GSEA had relatively poor results.
Over-representation analysis with a threshold of of the top 7 highest absolute value Dependency Map
correlations yielded the best results and is reported below.
GO Identifier
GO Name
GO Type
p-value
p-value (adj.)
q-value
Transcriptomics
The following table shows the significantly differentially expressed genes after knocking
out USP10 using CRISPR-Cas9.
There were too few differentially expressed genes to run a meaningful GSEA.
Literature Mining
INDRA was used to automatically assemble known mechanisms
related to USP10 from literature and knowledge bases.
The first section shows only DUB activity and the second shows all other results.
Deubiquitinase Activity
psp
cbn
pc
bel_lc
signor
biogrid
lincs_drug
tas
hprd
trrust
ctd
vhn
pe
drugbank
omnipath
conib
crog
dgi
|
rlimsp
isi
tees
geneways
eidos
trips
medscan
sparser
reach
Because USP10 is a p53 deubiquitinating enzyme, p53 ubiquitination was decreased by transfection of USP10 (compare lanes 3 and 4), whereas deubiquitination of p53 by USP10 was inhibited by co-transfection of USP10 and G3BP1 (compare lanes 4 and 5).
Overall, our study demonstrates that resveratrol directly targets G3BP1, which in turn prevents the G3BP1 and USP10 interaction and consequently increases USP10 regulated deubiquitination of p53 (XREF_FIG).
BECN1 also regulates the stability of the proteins USP10 and USP13, which might explain the novel observation 200 that BECN1 regulates p53 levels, as USP10 mediates p53 deubiquitylation.
Specific and potent autophagy inhibitor-1 (Spautin-1) was identified to inhibit USP10 and USP13, which deubiquitinate the Beclin 1 subunit of Vsp34 complex, and thus promoted the degradation of Vsp34 PI3 kinase complex.
It promotes the degradation of Vps34 complexes by inhibiting USP10 and USP13, two ubiquitin specific peptidases that target the deubiquitination of Beclin-1.
While A20 inhibits PtdIns3P signaling by removing the TRAF6-dependent Lys63-linked chains from Beclin 1, the enzymes USP10 and USP13 prevent PI3K-III complex components from their degradation and, therefore, support autophagy. Interestingly enough, USP10 also stabilizes p53, which, in turn, triggers the degradation of Beclin 1 and VPS34 in order to prevent autophagy.
Since USP10 mediates the deubiquitination of Beclin1 and reduced levels of USP10 leads to increased ubiquitination and degradation of Vps34 complexes, reduced levels of Vps34 complexes as a result of USP10 reduction may in turn lead to destabilization of USP13.
USP10 has also been shown to enhance autophagy by deubiquitinating beclin-1, a component of class-III PI3K complexes that catalyze the formation of phosphatidylinositol 3-phosphate at both autophagy initiation and autophagosome maturation steps.
Conversely, it was show that Beclin 1 is deubiquitinated by USP10 and USP13 and adding complexity, Beclin 1 itself controlled the protein stabilities of USP10 and USP13 by regulating their deubiquitinating activities, in turn regulating the levels of tumor suppressor p53 [XREF_BIBR].
Mechanistically, following the energy deprivation, USP10 largely deubiquitinates AMPKalpha so that its activating phosphorylation by LKB1 could be greatly enhanced.
As shown in XREF_FIG and XREF_SUPPLEMENTARY, knockdown of USP10 increased the ubiquitination of WT AMPKalpha; on the other hand, knockdown of USP10 did not affect ubiquitination levels of the AMPKalpha 4KR mutant (XREF_FIG and XREF_SUPPLEMENTARY).
We further overexpressed WT USP10 or catalytic inactive mutant in USP10 deficient cells and found that WT USP10, but not the CA mutant decreased ubiquitination of AMPKalpha (XREF_FIG and XREF_SUPPLEMENTARY), suggesting that USP10 regulates AMPKalpha ubiquitination in cells.
In this study, we identified that USP10 can deubiquitinate PTEN and AMPKalpha and the stabilization of these two proteins will subsequently suppress the activation of AKT and mTOR in HCC cells.
As shown in Figures 3 E and S3 D, knockdown of USP10 increased the ubiquitination of WT AMPKalpha; on the other hand, knockdown of USP10 did not affect ubiquitination levels of the AMPKalpha 4KR mutan[MISSING/INVALID CREDENTIALS: limited to 200 char for Elsevier]
We further overexpressed WT USP10 or CA mutant in USP10 deficient cells and found that WT USP10, but not the CA mutant, decreased ubiquitination of AMPKalpha, suggesting that USP10 regulates AMPKalpha[MISSING/INVALID CREDENTIALS: limited to 200 char for Elsevier]
In addition, in line with our study, two different groups have also reported that USP10 deubiquitinates and stabilizes PTEN and AMPKalpha in lung cancer and colon cancer cells [16, 27].
Recently, it was established that USP10 deubiquitinates AMPKalpha to promote its interaction with LKB1, its master regulator and thus enhances its activity.
Inhibition of USP10 suppresses post-endocytic de-ubiquitination of CFTR, and the cell targets the ion channel to the lysosome rather than recycling it into the apical membrane.
In a recent study, we demonstrated that USP10, a host cell DUB, deubiquitinates CFTR in endosomes, thereby reducing the lysosomal degradation of CFTR, and maintaining cell and plasma membrane CFTR XREF_BIBR.
USP10 decreases the ubiquitination of CFTR, whereas the knockdown of USP10 promotes the ubiquitination and reduction of CFTR at the cell surface [XREF_BIBR].
Functionally, Cif stabilizes an intracellular complex of a DUB (USP10) and G3BP1, preventing deubiquitylation of CFTR, which is required for recycling the receptor to the plasma membrane XREF_BIBR.
The ability of USP10 to efficiently deubiquitinate CFTR in the early endosome allows for efficient endocytic recycling of CFTR and thus the long half-life of CFTR (approximately 8-24 h in polarized human airway cells) in the plasma membrane.
MCPIP1 induction serves as a negative feedback mechanism for attenuating NF-kappaB activation in genotoxic response by mediating USP10 dependent deubiquitination of NEMO [13].
By mediating USP10 dependent deubiquitination of NEMO, MCPIP1 serves in a negative feedback mechanism for attenuation of NF-kappaB activation [XREF_BIBR].
One example is USP10 that requires the protein MCPIP-1 (monocyte chemotactic protein induced protein 1) to interact with and deubiquitinate its substrate NEMO inhibiting the NF-kappaB signalling cascade [XREF_BIBR].
Thus, by mediating USP10 dependent deubiquitination of NEMO, MCPIP1 induction serves as a negative feedback mechanism for attenuating genotoxic NF-kappaB activation.
Recent research has shown that PCNA is also modified by ISG15, and ISGylation of PCNA recruits USP10 to deubiquitinate PCNA, thereby regulating PCNA ubiquitination under UV irradiation induced stress.
An interesting study has recently shown that the deubiquitylation of mammalian PCNA, at least in the context of DNA damage induced by ultraviolet irradiation (UV), is aided by the deubiquitylating activity of USP10.
Collectively, the present results indicated that NLRP7 in CRC cells interacts with and is deubiquitinated by USP10, resulting in increased NLRP7 protein stability.
In addition, in line with our study, two different groups have also reported that USP10 deubiquitinates and stabilizes PTEN and AMPKalpha in lung cancer and colon cancer cells [16, 27].
In this study, we identified that USP10 can deubiquitinate PTEN and AMPKalpha and the stabilization of these two proteins will subsequently suppress the activation of AKT and mTOR in HCC cells.
Moreover, USP10 not only binds AR, resulting in increased transcriptional activity, but also deubiquitinates the histone variant H2A.Z, both of which are required for AR - mediated gene activation [XREF_BIBR, XREF_BIBR].
In addition, more bulky structures, SUMO (small ubiquitin related modifier) and ubiquitin are conjugated to histones (Galanty et al., 2009; Morris et al., 2009; Shioo and Eisenman, 2003; Thakar et al.[MISSING/INVALID CREDENTIALS: limited to 200 char for Elsevier]
USP10 directly deubiquitylates H2A.Z in vitro and in vivo, and reducing USP10 expression in prostate cancer cells results in elevated steady-state levels of mono-ubiquitylated H2A.Z (H2A.Zub1).
In addition, the deubiquitination of H2A.Z by USP10 is required for the androgen-receptor mediated transcriptional activation of hormone regulated genes [XREF_BIBR].
To test whether USP10 deubiquitinates and stabilizes TBP in mammalian cells, we overexpressed USP10 in 293T cells and monitored TBP ubiquitination levels in these cells.
To test whether USP10 deubiquitinates TBP through direct protein protein interactions, we used HA-TBP to co-IP with Flag-USP10 co-expressed in 293T cells.
Huwe1 as an E3 ligase targeting TBP for K48-linked ubiquitination and proteasome-mediated degradation; We found that Huwe1 activity on TBP is antagonized by the deubiquitinase USP10, which protects TBP from degradation.
We found TANK formed a complex with MCPIP1 (also known as ZC3H12A) and a deubiquitinase, USP10, which was essential for the USP10-dependent deubiquitination of TRAF6 and the resolution of genotoxic NF-κB activation upon DNA damage.
We found TANK formed a complex with MCPIP1 (also known as ZC3H12A) and a deubiquitinase, USP10, which was essential for the USP10 dependent deubiquitination of TRAF6 and the resolution of genotoxic NF-kappaB activation upon DNA damage.
Additionally, Liao and colleagues [XREF_BIBR] found that USP10 can promote leukemic cell proliferation by deubiquitinating and stabilizing the S-phase kinase associated protein 2 (SKP2) that acts as a co-regulator of BCR-ABL mediating its K63 linked ubiquitination and activation in CML cells [XREF_BIBR].
Subsequent deubiquitination of RPS2 and RPS3 by USP10 is critical for recycling of stalled ribosomes in a process known as ribosome associated quality control.
XREF_FIG, wild-type USP10, but not the catalytically-inactive USP10CA mutant, significantly reduces HDAC6 ubiquitination in 293T cells (comparing lanes 3 and 4 in the top panel).
USP10 deubiquitinates MSH2 in vitro and in vivo Moreover, the protein level of MSH2 is positively correlated with the USP10 protein level in a panel of lung cancer cell lines.
However, it is unclear whether USP10 antagonizes ubiquitination of mutp53 by other ubiquitin ligases, USP10 alters subcellular localization of mutp53, and USP10 plays a role in deubiquitination of different TP53 mutants.
In contrast, USP10, also a cytosolic DUB [XREF_BIBR], deubiquitylates TOP2A in complex with the E3 ligase RNF168 [XREF_BIBR], which is also important in DNA damage response signalling for double-strand break repair [XREF_BIBR].
Research on the endothelium revealed that USP10, as a regulatory protein, delayed the rate of NICD1 degradation by deubiquitinating the Notch1 receptor (Lim et al., 2019).
In P. aeruginosa, the OMV associated toxin CFTR-inhibitory factor (Cif) controls the host deubiquitylating enzyme USP10 to cause increased ubiquitylation of cystic fibrosis transmembrane conductance regulator (CFTR), which is involved in mucus production.
?Silencing of the DUB USP10 induces a buildup of ubiquitin on integrins beta1 and beta5 in cell lysates, whereas recombinant USP10 removes ubiquitin from these integrin subunits.
As shown in XREF_FIG, the coincubation of ubiquitinated Beclin1 with USP10 or USP13 but not a catalytically inactive USP10 mutant reduced the levels of Beclin1 ubiquitination.
Research on the endothelium revealed that USP10, as a regulatory protein, delayed the rate of NICD1 degradation by deubiquitinating the Notch1 receptor (Lim et al., 2019).
?Silencing of the DUB USP10 induces a buildup of ubiquitin on integrins beta1 and beta5 in cell lysates, whereas recombinant USP10 removes ubiquitin from these integrin subunits.
USP10, a primary cytoplasmic DUB, acts as an oncogene or a tumor suppressor by regulating various protein substrates, including FLT3, p53, AMPK, PTEN, etc.
Given our recent finding that USP10 deubiquitinates mutant FLT3, 18 coupled with reported studies showing that FLT3 and SYK are interacting partners with each other and are targets of the same E3 ligase c-CBL, XREF_BIBR, XREF_BIBR, XREF_BIBR - XREF_BIBR we hypothesised that USP10 may play a role in stabilisation of SYK.
Coexpression of USP10 together with Mdm2 decreased mutant p53 ubiquitination (XREF_SUPPLEMENTARY), while downregulation of USP10 increased mutant p53 ubiquitination (XREF_SUPPLEMENTARY), suggesting that USP10 also regulates mutant p53 ubiquitination.
Subsequent deubiquitination of RPS2 and RPS3 by USP10 is critical for recycling of stalled ribosomes in a process known as ribosome associated quality control.
The results showed that overexpression of wild-type USP10 promoted the deubiquitination of Sirt6 and inhibited the activation of downstream Akt signaling pathway, while mutant USP10 lost this function.
The result showed that both USP10 and USP11 specifically co-precipitated with NP-HA (lanes 1, 3 and 4, lower panel), consistent with the published result, and NP could be deubiquitinated by only USP11 but not USP10 (lanes 3 and 4, upper panel).
We identify 9 direct binding partners of p53 in the nuclear RNA interactome, including USP10, which deubiquitinates and activates p53 in response to DNA damage, and Sumo1, which can itself become covalently coupled to p53 to regulate its activity and subcellular localization (XREF_SUPPLEMENTARY) XREF_BIBR XREF_BIBR XREF_BIBR.
USP10 , upon ATM-dependent phosphorylation at threonine 42 and serine 337 residues , is stabilized and translocated to the nucleus to activate p53 through deubiquitinating activity , inducing tumor cell suppression [ 53 ] .
For example, USP7 regulates the stability of both p53 and Mdm2 and maintains p53 ubiquitination levels; 120 USP2 mediates the stability of Mdm2; 121 USP10 modulates p53 localization and stability; 122 OTUB1 abrogates p53 ubiquitination and activates p53.
As shown in XREF_FIG, downregulation of USP10 increased cancer cell proliferation in p53 +/+ cells, while USP10 expression levels have no apparent effect on proliferation in cells lacking p53.
It will be interesting to discover whether overexpression of USP7 could also rescue the diminished DNA damage induced p53 response caused by USP10 depletion.
Expression of USP10 significantly suppressed c-Myc transcriptional activity in p53 wildtype and p53 -/- HCT116 cells, but the levels of USP10 mediated suppression in c-Myc target gene transcription in p53-null cells were partially reversed.
In addition, USP10 suppresses the tumour cell growth in cells with wild-type p53, and USP10 expression is down-regulated in a high percentage of clear cell carcinomas known to have few p53 mutations [108].
Indeed, USP10 depletion attenuates DNA damage induced stabilization of p53, an effect that was rescued by overexpression of wild-type USP10 but not by mutant USP10 lacking ATM phosphorylation sites.
Consistent with this notion, USP10 expression is frequently lost in renal cell carcinoma, and overexpression of USP10 suppresses cell transformation and tumorigenesis in a p53 dependent fashion.
Downregulation of p53 abolished the inhibitory effect of USP10 on tumor growth (XREF_FIG and data not shown), confirming that USP10 inhibits cancer cell growth by stabilizing p53.
For example, USP10 interacts with G3BP2 to block p53 signal transduction, leading to poor prognosis in prostate cancer [XREF_BIBR]; USP44 promotes the development of prostate cancer by stabilizing EZH2 [XREF_BIBR], and USP2a enhances c-Myc expression via microRNA related regulation and thus promotes tumourigenesis [XREF_BIBR].
Both, the DUB HAUSP (herpesvirus associated ubiquitin specific protease) and USP10 (ubiquitin specific protease 10), targeting poly-ubiquitinated p53, have been shown to restore p53 levels even when Hdm2 is overexpressed.
Furthermore, overexpression of USP10 in 786-O cells increases levels of mutp53, leading to enhanced colony formation and proliferation, which is nullified by depletion of mutp53.
Consistent with this study, we show that increased USP10 expression in mutant p53 background increases p53 levels and promotes cancer cell proliferation, while downregulation of USP10 inhibits cancer cell growth.
Interestingly, downregulation of USP10 significantly decreased p53 stabilization and the expression of p53 target genes p21 and Bax after DNA damage (XREF_FIG).
To confirm the role of USP10 in regulating p53 levels, we depleted USP10 using USP10 specific shRNA, and found that downregulation of USP10 decreased p53 protein levels with no effect on p53 mRNA levels (XREF_FIG).
Collectively, these results indicate that USP10 inhibits cytokine deprivation induced apoptosis of IVC-LSK cells in a deubiquitinase dependent but ROS independent manner.
XREF_FIG, overexpression of either HDAC6 or USP10 in USP10 knockdown cells significantly increased cell survival post-cisplatin treatment and reduced apoptosis as shown by the level of cleaved PARP-1.
USP10 also has deubiquitinase independent functions, such that USP10 inhibits apoptosis by reducing reactive oxygen species (ROS) production induced by an oxidative stress inducer arsenite.
A deubiquitinase-inactive USP10 mutant (USP10/C418A) did not inhibit cytokine deprivation-induced apoptosis of IVC-LSK cells, indicating that a factor deubiquitinated by USP10 inhibits apoptosis of IVC-LSK cells.
However, we could not exclude the possibility that USP10 inhibits apoptosis by promoting degradation of pro-apoptotic protein(s) by aggresome-mediated autophagy.
On exposure to arsenic, an oxidative stress inducer, USP10 is recruited into stress granules (SGs), and USP10 containing SGs reduce reactive oxygen species (ROS) production and inhibit ROS dependent apoptosis.
Studies using USP10 mutants, including USP10/77 -792 and USP10/95-792, indicate that USP10 's interaction with G3BP1 is essential for inhibition of ROS dependent apoptosis and for USP10 incorporation into stress granules.
In conclusion, these results suggest that USP10 promotes proliferation and migration and inhibits apoptosis of endometrial stromal cells in endometriosis through activating the Raf-1/MEK/ERK pathway.
USP10-knockout indicated that USP10, through augmenting formation of SGs, reduced reactive oxygen species (ROS) production and inhibited ROS dependent apoptosis.
USP10 promotes proliferation and migration and inhibits apoptosis of endometrial stromal cells in endometriosis through activating the Raf-1/MEK/ERK pathway.
USP10 Heterozygote mice exhibited exacerbated hepatic I/R injury, as evidenced by enhanced liver inflammation via the NF-kappaB signalling pathway and increased hepatocyte apoptosis.
In vitro data showed that USP10 deficiency reduced proliferation and migration of rat thoracic aorta smooth muscle cells (A7r5) and human aortic smooth muscle cells (HASMCs).
Indeed, downregulation of USP10 decreases p53 stability and increases cancer cell proliferation XREF_BIBR, thus projecting a role as a tumor suppressor.
In conclusion, these results suggest that USP10 promotes proliferation and migration and inhibits apoptosis of endometrial stromal cells in endometriosis through activating the Raf-1/MEK/ERK pathway.
USP10 promotes proliferation and migration and inhibits apoptosis of endometrial stromal cells in endometriosis through activating the Raf-1/MEK/ERK pathway.
For example, in hepatocellular carcinoma, Zhu et al. reported that USP10 promotes proliferation [XREF_BIBR], whereas Lu et al. found that USP10 suppresses tumor progression by inhibiting mTOR activation [XREF_BIBR].
Specifically, USP10 activates PTEN by preventing its K63 linked polyubiquitination mediated by TRIM25 and suppresses the AKT and mTOR signaling pathway thereby inhibiting NSCLC proliferation, indicating that it may be a potential drug target for cancer treatment.
USP10 overexpression promoted ectopic endometrial stromal cell migration and proliferation, suppressed cell apoptosis, and activated MEK and ERK signaling that is a critical downstream target of the serine/threonine protein kinase Raf-1, which was significantly blocked by PD98059.
Consistent with this study, we show that increased USP10 expression in mutant p53 background increases p53 levels and promotes cancer cell proliferation, while downregulation of USP10 inhibits cancer cell growth.
Furthermore, the double knock-down of G3BP1 and USP10 rescued the inhibition of proliferation induced by G3BP1 depletion in HCT116 (XREF_FIG) and SK-MEL-5 cells (XREF_SUPPLEMENTARY).
Consistent with its molecular activity, re-expression of USP10 suppressed NSCLC cell proliferation and migration while knockout of USP10 promoted NSCLC cell proliferation and migration.
On the other hand, reconstitution of USP10 in cells with USP10 downregulation inhibited cancer cell proliferation (XREF_FIG), suggesting the effect of USP10 knockdown is specific.
Previous studies have shown that USP10 antagonizes c-Myc transcriptional activation that could promote Sirt6 stabilization to suppress tumor formation.
It has been reported that one of the molecular mechanisms underlying USP10 tumor-suppressive functions is that it protects p53 from degradation, raising the possibility that USP10 also antagonizes c-Myc transcriptional activity through p53.
To further prove the principle that USP10 suppresses c-Myc transcriptional activity through both SIRT6 and p53, we tested whether knockdown of SIRT6 rescues this USP10 suppressive activity.
We then used SIRT6-null mouse embryonic fibroblasts (MEFs) to prove the principle that SIRT6 is another downstream factor in USP10 mediated c-Myc suppression.
To our surprise, SIRT6 gene suppression resulted in a lower level of increase in c-Myc target gene expression than that of USP10 knockdown, implying that additional factors may contribute to USP10 mediated c-Myc suppression.
USP10 also antagonizes c-myc transcription through deubiquitination of SIRT6, a histone deacetylase, and NF-kappaB signaling through deubiquitination of NEMO [XREF_BIBR].
It was shown that knockdown of USP10 decreased Sirt6 expression , whereas overexpression of USP10 increased Sirt6 protein expression in primary cardiomyocytes after Ang II stimulation ( Figure 6C and 6D ) .
It was shown that knockdown of USP10 decreased Sirt6 expression, whereas overexpression of USP10 increased Sirt6 protein expression in primary cardiomyocytes after Ang II stimulation.
It was shown that knockdown of USP10 decreased Sirt6 expression, whereas overexpression of USP10 increased Sirt6 protein expression in primary cardiomyocytes after Ang II stimulation.
In addition, USP10 suppresses the tumour cell growth in cells with wild-type p53, and USP10 expression is down-regulated in a high percentage of clear cell carcinomas known to have few p53 mutations [108].
Downregulation of p53 abolished the inhibitory effect of USP10 on tumor growth (XREF_FIG and data not shown), confirming that USP10 inhibits cancer cell growth by stabilizing p53.
In addition, USP10 suppresses the tumour cell growth in cells with wild-type p53, and USP10 expression is down-regulated in a high percentage of clear cell carcinomas known to have few p53 mutations [XREF_BIBR].
Given USP10 also regulates p53 expression and suppresses tumor cell growth, phosphorylation of USP10 under energy stress might contribute to p53 level increase and tumor suppression.
On the other hand, shRNA mediated USP10 knockdown caused more vigorous tumor cell growth of both wildtype and p53-null cells, confirming the tumor-suppressive function of USP10 (XREF_FIG, XREF_SUPPLEMENTARY).
Moreover, USP10 inhibited cell growth and invasion in lung cancer [XREF_BIBR], and was an independent factor for the prognosis of gastric carcinoma [XREF_BIBR].
Consistent with this study, we show that increased USP10 expression in mutant p53 background increases p53 levels and promotes cancer cell proliferation, while downregulation of USP10 inhibits cancer cell growth.
Consistent with this study, we show that increased USP10 expression in mutant p53 background increases p53 levels and promotes cancer cell proliferation, while downregulation of USP10 inhibits cancer cell growth.
To obtain information describing how USP10 inhibits MG-132-induced cell death, we measured cell death of USP10-KD cells expressing several USP10 mutants.
Given that USP10-WT, USP10 C424A, and USP10 96-798, but not USP10 1-214, in USP10-KD cells promoted p62 aggregation and aggresome formation (XREF_FIG G and XREF_SUPPLEMENTARY A-S5C), these results suggested that USP10 inhibits cell death induced by MG-132 by promoting aggresome formation and p62 aggregation.
USP10 inhibited cell death induced by PI, and the inhibition correlated with aggresome and aggregate inducing activity (XREF_FIG and XREF_SUPPLEMENTARY).
Similar to Beclin 1 knockdown, we found that suppression of the ubiquitin specific peptidase, USP10, or a small molecule inhibitor of the deubiquitinases USP10 and USP13, i.e., spautin-1 XREF_BIBR, can increase radiation induced DSBs and promote tumor cell death.
These results indicated that USP10 and p62 cooperatively inhibit MG-132-induced cell death by promoting the formation of aggresomes and p62 aggregates.
While USP10/77 -792 and USP10/95 -792 mutants inhibited cell death of IVC-LSK cells as efficiently as USP10-WT, a deubiquitinase inactive mutant USP10 and C418A showed minimal activity and failed to inhibit cytokine deprivation induced cell death after 44and 62hr of starvation.
Similar to Beclin 1 knockdown, we found that suppression of the ubiquitin specific peptidase, USP10, or a small molecule inhibitor of the deubiquitinases USP10 and USP13, i.e., spautin-1 XREF_BIBR, can increase radiation induced DSBs and promote tumor cell death.
Consistent with our screening results on the effect of USP10 siRNA, pretreatment with spautin-1, a specific inhibitor of USP10, markedly inhibited curcumin induced morphological changes of mitochondria and subsequent paraptotic cell death in various breast cancer cells.
Additional work will be needed to investigate the detailed underlying mechanism by which USP10 contributes to paraptotic cell death in malignant breast cancer cells.
Additional work is needed to investigate the detailed underlying mechanism by which USP10 contributes to mitochondrial dilation and subsequent paraptotic cell death in malignant breast cancer cells.
discovered the interaction of G3BP1 with ubiquitin specific protease 10 (USP10), and they concluded that G3BP1 might restrict the deubiquitinating activity of USP10.
Anisonov et al. [91] also found that USP10 is inhibited by G3BP1 in a mechanism similar to that for NUP62, which indicates an analogous cascading route from SARS-CoV-2 to PD for this protein.
Surprisingly, the human homolog of Bre5, G3BP1, inhibits the activity of USP10, at least in vitro, indicating that cofactors can either restrict or enhance protease activity.
Notably, siRNA mediated knockdown of G3BP1 significantly increased the abundance of CFTR, most likely because endogenous G3BP1 inhibits USP10 (XREF_FIG).
It appears therefore that the FGDF mediated G3BP and USP10 complex is mutually inhibitory, with G3BP inhibiting the DUB activity of USP10 and USP10 inhibiting the SG nucleating function of G3BP.
Anisonov et al. [91] also found that USP10 is inhibited by G3BP1 in a mechanism similar to that for NUP62, which indicates an analogous cascading route from SARS-CoV-2 to PD for this protein.
In airway epithelial cells treated with the CFTR inhibitory factor (Cif), the Ras GTPase-activating protein-binding protein 1 (G3BP1) inhibits the ubiquitin-specific protease USP10.
Interestingly G3BP1 modulates USP10 deubiquitinase activity, as well as interacts and co-localizes with HCV NS5B protein and RNA to modulate HCV replication.
Usp10 is known to enhance AR transcriptional activity [XREF_BIBR, XREF_BIBR] and Usp22 and Usp26 have been found in complexes with AR [XREF_BIBR, XREF_BIBR].
Overexpression of wild-type USP10 stimulated AR activity as revealed by reporter constructs harbouring selective androgen response elements, non selective steroid response elements or the mouse mammary tumour virus promoter.
Cell based transactivation assays in PC-3/AR cells revealed that overexpression of wild-type USP10, but not of an enzymatically inactive form, stimulated AR activity mediated by reporter constructs harbouring selective androgen response elements (AREs), non selective steroid response elements (SREs) or the mouse mammary tumour virus (MMTV) promoter.
RNF6 and USP10, which modulate androgen receptor function, showed correlated genomic loss and lower expression in a subset of tumors and gain and higher expression in others.
In contrast, the siRNA luciferase screen in LNCaP cells showed that transfection with validated siRNAs targeting USP10 potentiated AR transcriptional activity.
Indeed, a recent study showed that a small molecule, Spautin-1, promoted the degradation of Vps34 by inhibiting two ubiquitin specific proteases USP10 and USP13 that regulate the stability of the Vps34 complex [XREF_BIBR].
SBI blocks the kinase activity of ULK1, diminishing the phospho regulated capacity of beclin-1 to engage with its binding partners (Egan et al., 2015) and Spautin-1 inhibits the USP10 and USP13 hydrol[MISSING/INVALID CREDENTIALS: limited to 200 char for Elsevier]
Molecular analysis revealed that Spautin-1 directly inhibits the activity of the deubiquitinating enzymes (DUBs) ubiquitin specific protease 10 (USP10) and USP13.
To further determine whether USP10 could be a druggable target in these patients, we evaluated the ex vivo antineoplastic effect of pharmacological inhibition of USP10 by Spautin-1 on primary monocytes from 16 patients with CML.
Spautin-1 inhibits the activity of two ubiquitin specific peptidases, USP10 and USP13, causing an increase in proteasomal degradation of class III PI3 kinase complexes, which have been shown to regulate autophagy [XREF_BIBR].
To further prove the principle that USP10 suppresses c-Myc transcriptional activity through both SIRT6 and p53, we tested whether knockdown of SIRT6 rescues this USP10 suppressive activity.
Overexpressing USP-10 decreased the amount of ubiquitinated CFTR and increased its abundance in the plasma membrane of human airway epithelial cells [XREF_BIBR].
small interference RNA mediated knockdown of USP10 increased the amount of ubiquitinated CFTR and its degradation in lysosomes, and reduced both apical membrane CFTR and CFTR mediated chloride secretion.
Moreover, a dominant negative USP10 (USP10-C424A) increased the amount of ubiquitinated CFTR and its degradation, whereas overexpression of wt-USP10 decreased the amount of ubiquitinated CFTR and increased the abundance of CFTR.
Moreover, a dominant negative USP10 (USP10-C424A) increased the amount of ubiquitinated CFTR and its degradation, whereas overexpression of wt-USP10 decreased the amount of ubiquitinated CFTR and increased the abundance of CFTR.
For example, UCH-L3 localizes to endosomes and regulates the surface levels of ENaC in kidney cells, USP-10 localizes to endosomes and promotes CFTR recycling to the epithelial cell surface, USP20 and USP33 control recycling of beta 2 ARs, and both AMSH and USP8 and UBPY are endosome associated DUBs implicated in regulating EGFR degradation.
Moreover, a dominant negative USP10 (USP10-C424A) increased the amount of ubiquitinated CFTR and its degradation, whereas overexpression of wt-USP10 decreased the amount of ubiquitinated CFTR and increased the abundance of CFTR.
Thus, the goal of this study was to test the hypothesis that Cif inhibits USP10, which increases the amount of ubiquitinated CFTR that is degraded in lysosomes, thereby reducing cell and plasma membrane CFTR level.
Thus, the goal of this study was to test the hypothesis that Cif inhibits USP10, which increases the amount of ubiquitinated CFTR that is degraded in lysosomes, thereby reducing cell and plasma membrane CFTR level.
Finally, if Cif stabilizes an inhibitory interaction between G3BP1 and USP10, silencing G3BP1 should reduce the Cif induced decrease in USP10 activity as well as the Cif induced increase in ubiquitinated CFTR, and its degradation in lysosomes.
For example , in hepatocellular carcinoma , Zhu et al. reported that USP10 promotes proliferation [ 40 ] , whereas Lu et al. found that USP10 suppresses tumor progression by inhibiting mTOR activation [ 41 ] .
USP10, upon ATM-dependent phosphorylation at threonine 42 and serine 337 residues, is stabilized and translocated to the nucleus to activate p53 through deubiquitinating activity, inducing tumor cell suppression [53].
On the other hand , USP10 , a p53 deubiquitinase , serves as a positive regulator of p53 ; inhibition of USP10 could suppress cancer by degrading oncogenic p53 mutants ( Figure 2b ) [ 32 ] .
It has been reported that USP10 mediates cancer progression via stabilizing some substrates , such as p53 , STRT6 , AMPK , FLT3 and androgen receptor [ 20-24 ] .
USP10 may prevent G3BP from nucleating SG assembly by locking G3BP in a conformation that influences the NTF2 like domain and mediates or prevents G3BP oligomerization.
It is also possible that USP10 blocks the helicase function of G3BP, as helicase activity of some proteins, e.g., DDX6 and RCK, has been shown to be required for RNA granule assembly.
However, USP10 KD also reduces expression of G3BP1 and G3BP2 (to 58% and 77% of control values, respectively; XREF_FIG), suggesting that the SG inhibition caused by USP10 KD may be caused by reduced levels of G3BP.
In this study, our western blotting and RT-qPCR assays revealed that USP10 inhibition promotes the degradation of CD36 protein but does not change its mRNA level.
In this study , our western blotting and RT-qPCR assays revealed that USP10 inhibition promotes the degradation of CD36 protein but does not change its mRNA level .
These results suggest that USP10 deubiquitinase activity is required for its effects in AMPK activation and cellular metabolism.We then explored the mechanism by which USP10 modulates AMPK activation,[MISSING/INVALID CREDENTIALS: limited to 200 char for Elsevier]
The fact that USP10 also positively regulates beclin-1 and AMPK would make pharmacologic activators of USP10 particularly effective as autophagy enhancers.
Only WT USP10, but not the CA mutant could rescue AMPK activation triggered by USP10 RNAi (XREF_FIG), suggesting that USP10 deubiquitinase activity is required for AMPK activation.
As shown in Figure 4 B, the phosphorylation of USP10 increased significantly after glucose starvation, suggesting that USP10 might be a substrate of AMPK.
Only WT USP10, but not the CA mutant, could rescue AMPK activation triggered by USP10 RNAi, suggesting that USP10 deubiquitinase activity is required for AMPK activation.
As shown in XREF_FIG, the phosphorylation of USP10 increased significantly after glucose starvation, suggesting that USP10 might be a substrate of AMPK.
Cells with an exon 3 deletion may express an FGDF containing inhibitory fragment of USP10, which would suppress SGs as does USP10 1-40 (XREF_FIG) and explain the apparent contradiction.
Tet induced GFP-USP10 expression prevents AS and CZ induction of SGs (XREF_FIG) but does not alter stress induced polysome disassembly (XREF_FIG), indicating that GFP-USP10 inhibits the cytoplasmic condensation of mRNPs into SGs.
Here, we have shown that overexpression of EGFP-USP10, but not a mutant lacking an intact FGDF-motif, efficiently blocks the formation of SGs (XREF_FIG).
When mCherry tagged USP10 is cotransfected with GFP-G3BP1, both proteins colocalize in SGs (XREF_FIG, 4), but mCherry-USP10 coexpressed with GFP-Caprin1 inhibits SGs even upon AS treatment (XREF_FIG, 5 and 6), suggesting that USP10 and Caprin1 compete for limiting G3BP.
Rescue experiments using a G3BP1 mutant that lacks the ability to bind Caprin1 or USP10 rescues SGs assembly, whereas other phosphomimetic mutants of G3BP1 (G3BP1-S149E) fail to do that [XREF_BIBR].
In addition, the overexpression of USP10 without stress stimuli in HT22 cells induced TIA1/Tau/USP10 positive SGs in a deubiquitinase independent manner.
We further found that only USP10-WT, but not USP10-CA, increased the protein level of SKP2, suggesting that deubiquitinating activity of USP10 is required for SKP2 enrichment.
The result showed that loss of USP10 significantly decreased the expression of SKP2, as well as the phosphorylation and downstream signals of Bcr-Abl, suggesting that USP10 is required for the expression of SKP2 and the phosphorylation of Bcr-Abl in CML cells.
Notably, genetic or pharmacological inhibition of USP10 using Spautin-1 prominently decreased the stability of endogenous SKP2 protein, suggesting that USP10 inhibits the degradation of SKP2 in vivo.
On exposure to arsenic, an oxidative stress inducer, USP10 is recruited into stress granules (SGs), and USP10 containing SGs reduce reactive oxygen species (ROS) production and inhibit ROS dependent apoptosis.