| 2015 |
KPC1 (RNF123) is the E3 ubiquitin ligase that binds to the ankyrin repeats domain of NF-κB1 p105, ubiquitinates it, and mediates its limited proteasomal processing to the p50 active subunit both under basal conditions and following signaling. Overexpression of KPC1 inhibits tumor growth via excessive generation of p50, and the resulting p50 homodimer modulates transcription in place of the tumorigenic p50-p65 heterodimer. |
Co-immunoprecipitation, in vitro ubiquitination assay, overexpression studies, tumor xenograft models, transcript analysis |
Cell |
High |
25860612
|
| 2008 |
USP19, a deubiquitinating enzyme, interacts with and stabilizes KPC1 protein by reversing its ubiquitination, thereby modulating p27(Kip1) levels and cell proliferation. Depletion of USP19 reduces KPC1 levels and causes G1/S accumulation that is rescued by KPC1 overexpression or p27 knockout. |
Co-immunoprecipitation, RNA interference, proteasome inhibitor treatment, cell cycle analysis, rescue experiments with KPC1 overexpression |
Molecular and cellular biology |
High |
19015242
|
| 2012 |
RNF123 ubiquitin ligase binds HP1α and HP1β via a canonical PXVXL pentapeptide motif in its N-terminus and targets them for proteasomal degradation. In lamin A/C knockdown cells, RNF123 is upregulated and mediates degradation of HP1α and HP1β (but not HP1γ). Mutation of the PXVXL motif abolishes HP1 binding and degradation. |
GFP-tagged RNF123 ectopic expression, RNAi knockdown of RNF123, mutational analysis of PXVXL motif, FRAP analysis, Western blot in HeLa cells |
PloS one |
High |
23077635
|
| 2016 |
RNF123 is a negative regulator of RIG-I and MDA5 antiviral signaling. RNF123 associates with the N-terminal CARD domains of RIG-I and MDA5 in a viral infection-inducible manner and competes with the downstream adaptor VISA/MAVS for CARD binding, thereby inhibiting IFN-β production. This inhibitory function requires the SPRY and coiled-coil domains of RNF123 but NOT the RING domain, indicating an E3 ligase-independent mechanism. |
Overexpression, knockdown and knockout of RNF123, endogenous and exogenous Co-immunoprecipitation, domain deletion mutant analysis, IFN-β reporter assays with SeV and EMCV |
EMBO reports |
High |
27312109
|
| 2018 |
KPC1/RNF123 directly ubiquitinates the ETV6-NTRK3 (EN) chimeric oncoprotein in vitro, and its overexpression decreases EN protein levels. IGF1R signaling protects EN from KPC1/RNF123-mediated proteasomal degradation; blocking IGF1R promotes rapid EN ubiquitylation and degradation that is reversed by KPC1 knockdown. |
SILAC-based MS interactomics, in vitro ubiquitination assay, KPC1 overexpression and knockdown, IGF1R inhibitor treatment in fibroblast, breast epithelial, and leukemia cell lines |
The Journal of biological chemistry |
High |
29903916
|
| 2020 |
KPC1 promotes proteasomal degradation of Bax and prevents Bax translocation to mitochondria, thereby reducing apoptosis in cardiomyocytes under hypoxia/reoxygenation. This effect is abolished by the proteasome inhibitor MG132, confirming a proteasome-dependent mechanism. |
KPC1 overexpression and shRNA knockdown in H9c2 cells and rat I/R model, Western blot for Bax protein, MMP assay, cytochrome c release, MG132 proteasome inhibition |
Journal of cellular physiology |
Medium |
31148189
|
| 2020 |
RNF123 overexpression in IDH WT glioblastoma cells reduces NF-κB1 p50 levels and negatively regulates SerpinE1 expression downstream of the miR-155-5p/RNF123/NF-κB1-p50 axis, thereby reducing proliferation and invasion. |
RNF123 overexpression in GB cell lines, RNA-sequencing, reverse-phase protein arrays, in vitro functional assays, miR-155-5p overexpression |
Cancers |
Medium |
32349217
|
| 2020 |
KPC1-generated excess p50 suppresses tumor growth via multiple mechanisms: (1) downregulation of PD-L1 expression (abrogated by p65 overexpression), and (2) upregulation of pro-inflammatory chemokines CCL3, CCL4, and CCL5, which recruit NK cells and macrophages into tumors. |
KPC1 overexpression in cancer cells and tumor xenograft models, p65 co-overexpression rescue, gene expression analysis, immune cell recruitment assays |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
33168738
|
| 2021 |
The p105-binding site on KPC1 consists of a seven amino acid sequence (WILVRLW, residues 968–974). Attaching this short stretch to the RING-finger domain fragment was sufficient to bind p105, ubiquitinate it, and suppress tumor growth in vivo. Fusion of these seven amino acids to a pVHL-binding ligand created a PROTAC that stimulated p105 ubiquitination in cell-free systems and its processing to p50 in cells. |
Domain deletion and mutagenesis of KPC1, in vitro ubiquitination assay with PROTAC, cell-free processing assay, xenograft tumor model |
Proceedings of the National Academy of Sciences of the United States of America |
High |
34873064
|
| 2022 |
ADAR1-mediated A-to-I RNA editing of KPC1 results in a methionine-to-valine substitution at residue 8 (p.M8V), which weakens the affinity of KPC1 for its substrate NF-κB1 p105, thereby reducing ubiquitination and proteasomal processing of p105 to p50 and enhancing oncogenic NF-κB signaling. |
Sanger sequencing validation of RNA editing, molecular interaction assays, in vitro and in vivo functional assays in iCCA cells, NF-κB signaling analysis |
Journal of experimental & clinical cancer research : CR |
Medium |
36476255
|
| 2020 |
RNF123 interacts with Dvl2 and participates in CCNG2-induced polyubiquitination and proteasomal degradation of Dvl2, thereby suppressing JNK-dependent Wnt/PCP signaling in trophoblast cells. RNF123 siRNA reversed CCNG2-induced Dvl2 degradation and restored Wnt/PCP-JNK signaling. |
Co-immunoprecipitation, polyubiquitination assay, siRNA knockdown, Western blot, Wnt/PCP-JNK signaling readouts in HTR8/SVneo cells |
FASEB journal |
Medium |
33205477
|
| 2023 |
RNF123 binds the SH2 domain of SOCS1 via its RING domain, facilitates K48-linked ubiquitination specifically at K114 and K137 residues of SOCS1, and promotes SOCS1 proteasomal degradation, thereby promoting TLR3- and IRF7-mediated type I IFN production during duck Tembusu virus infection. |
Co-immunoprecipitation, in vivo ubiquitination assay with site-specific lysine mutants (K114R, K137R), proteasome inhibitor treatment, IRF7/TLR3 reporter assays |
Journal of virology |
Medium |
37014223
|
| 2024 |
RNF123 directly interacts with and ubiquitinates PFKP (6-Phosphofructo-2-kinase), leading to PFKP degradation and inhibition of glycolysis, which suppresses breast cancer cell viability, cell cycle progression, and colony formation. |
Co-immunoprecipitation, ubiquitination assay, lentiviral overexpression/knockdown, glycolysis assays (ECAR, lactate, ATP), xenograft tumor model |
Naunyn-Schmiedeberg's archives of pharmacology |
Medium |
39725718
|
| 2024 |
KPC1 (RNF123) forms a complex with vimentin, ubiquitinates it, and promotes its degradation. KPC1 overexpression in HEK293T cells downregulates vimentin, while KPC1 deletion in HAP1 cells upregulates vimentin. Downregulation of vimentin mediates at least part of KPC1's anti-migratory and anti-tumorigenic effects. |
Co-immunoprecipitation, in vitro ubiquitination assay, KPC1 overexpression in HEK293T, CRISPR-based KPC1 deletion in HAP1 cells, tumor model in mice |
Biochemical and biophysical research communications |
Medium |
39732122
|
| 2025 |
RNF123 catalyzes unanchored K63-linked ubiquitination of NEK7, which prevents NEK7-mediated dissociation of inactive cage-like NLRP3 aggregates and subsequent NLRP3 inflammasome assembly. The Crohn's disease-associated variant RNF123-R854H aggravates colitis through the NLRP3-dependent pathway. K63-linked polyubiquitin chains can be captured by NEK7 in vitro and inhibit NEK7-licensed NLRP3 inflammasome assembly. |
In vitro ubiquitination assay with unanchored polyubiquitin chain analysis, Co-immunoprecipitation, RNF123-deficient mice, R854H knock-in mouse model, DSS colitis, LPS endotoxemia, Alum peritonitis models, in vitro NEK7 capture assay |
Proceedings of the National Academy of Sciences of the United States of America |
High |
41719337
|
| 2025 |
KPC1 (RNF123) binds ZEB1 and promotes its ubiquitination and proteasomal degradation, thereby suppressing cadherin switching and cell motility in melanoma. Loss of KPC1 prevents ZEB1 proteasomal degradation and increases mesenchymal marker expression and cell migration. |
Co-immunoprecipitation, ubiquitination assay, KPC1 knockdown/overexpression, single-cell transcriptomic analyses, migration assays |
Cell death & disease |
Medium |
41429767
|
| 2025 |
RNF123 targets PKM2 for ubiquitination in high-glucose-stimulated Müller cells, promoting PKM2 degradation and thereby reducing glycolysis and Müller cell activation. HG-induced downregulation of RNF123 is mediated upstream by ALKBH5 and IGF2BP1 via m6A modification, which is itself controlled by histone lactylation. |
Co-immunoprecipitation, ubiquitination assay, RNF123 overexpression and knockdown in MIO-M1 cells, ALKBH5/IGF2BP1 modulation, diabetic rat in vivo model |
Journal of translational medicine |
Medium |
41094513
|
| 2025 |
RNF123 directly binds the N-terminal domain of PRDX1 and adds a K48-linked ubiquitin chain at the K7 site of PRDX1, promoting its proteasomal degradation. RNF123-mediated PRDX1 degradation increases ROS levels in cardiomyocytes, driving pathological cardiac hypertrophy. RNF123 deficiency mitigates Ang II- and TAC-induced cardiac hypertrophy and dysfunction in mice. |
LC-MS/MS combined with Co-IP to identify PRDX1, K48-linkage-specific ubiquitination assay with K7R mutant, RNF123 knockout mice, Ang II infusion and TAC surgery models, NRVMs KD/OE |
Acta physiologica (Oxford, England) |
High |
42106994
|
| 2011 |
Following spinal cord injury, KPC1 is upregulated predominantly in astrocytes, and increased interaction between KPC1 and p27(Kip1) was detected by co-immunoprecipitation 4 days post-injury. KPC1 upregulation correlates inversely with p27(Kip1) and is associated with astrocyte proliferation, as demonstrated in LPS-stimulated astrocytes in vitro. |
Co-immunoprecipitation, Western blot, immunohistochemistry, immunofluorescence in rat SCI model and LPS-stimulated astrocytes |
Neurochemical research |
Low |
21229311
|
| 2011 |
miR-155 targets KPC1 (Kip1 ubiquitination-promoting complex 1) as a functional target and indirectly regulates p27(Kip1) protein levels by reducing KPC1 expression in dendritic cells, thereby contributing to DC apoptosis. |
miRNA overexpression and silencing in human DCs, miR-155 knockout mice DCs, Western blot for p27(Kip1) and KPC1 protein levels |
Blood |
Medium |
21355095
|