Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Modulation of proteostasis by the ubiquitin-conjugating enzyme UBE2N in immunoproteasome-positive AML

ABSTRACT: Altered protein homeostasis through proteasomal degradation of ubiquitinated proteins is a hallmark of many cancers. Ubiquitination, coordinated by E1, E2, and E3 enzymes, involves up to 40 E2-conjugating enzymes in humans to specify substrate and ubiquitin linkages. In a screen for E2 dependencies in AML, UBE2N emerged as the top candidate. To investigate UBE2N's role in AML, we characterized an enzymatically-defective mouse model of UBE2N, revealing UBE2N's requirement in AML without significant impact on normal hematopoiesis. Unlike other E2s, which mediate Lysine-48 (K48) polyubiquitination and degradation of proteins, UBE2N exclusively synthesizes K63-linked chains, stabilizing or altering protein function. Proteomic analyses and a whole genome CRISPR-activation screen in pharmacologically and genetically UBE2N-inhibited AML cells unveiled a network of UBE2N-regulated oncoproteins. UBE2N inhibition reduced their protein levels, leading to increased K48-linked ubiquitination and degradation through the immunoproteasome and revealing UBE2N activity is enriched in immunoproteasome-positive AML. Furthermore, an interactome screen identified TRIM21 as the E3 ligase partnering with activated UBE2N in AML to modulate UBE2N-dependent proteostasis. In conclusion, UBE2N maintains proteostasis in AML by stabilizing oncoproteins through K63-linked ubiquitination and prevention of K48 ubiquitin-mediated degradation through the immunoproteasome. Thus, inhibition of UBE2N catalytic function suppresses leukemic cells through selective degradation of critical oncoproteins in immunoproteasome-positive AML.

ORGANISM(S): Mus musculus

PROVIDER: GSE286041 | GEO | 2025/04/19

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The UBA domain of Ubc1 (Ube2K) Facilitates the Assembly of K48/K63-Branched Ubiquitin Chains

Project description:The assembly of a specific polymeric ubiquitin (Ub) chain on a target protein is a key event in the regulation of numerous cellular processes. Yet, the mechanisms that govern the selective synthesis of particular polyubiquitin signals remain enigmatic. The ubiquitin-conjugating (E2) enzymes Ubc1 in yeast and Ube2K in mammals exclusively generate polyubiquitin linked through lysine 48 (K48). Uniquely among E2 enzymes, Ubc1 and Ube2K harbor a Ub binding UBA domain with unknown function. We found that this UBA domain preferentially interacts with Ub chains linked through lysine 63 (K63). Based on structural modeling, in vitro ubiquitination experiments and NMR studies, we propose that the UBA domain aligns Ubc1 with K63-linked polyubiquitin and facilitates the selective assembly of K48/K63-branched Ub molecules. Genetic experiments link the activity of the UBA domain and hence the formation of this unusual Ub chain topology to the maintenance of cellular proteostasis.

2021-03-02 | PXD022621 | Pride

RNA sequencing of MOLM-13 cells transduced with lentivirally expressed UBE2N or control short hairpin RNAs

Project description:Dysregulation of innate immune and inflammatory signaling pathways is implicated in various hematologic malignancies. Yet, these pathways have not been systematically examined in acute myeloid leukemia (AML). We report that AML hematopoietic stem and progenitor cells (HSPCs) exhibit a high frequency of dysregulated innate immune-related and inflammatory pathways, referred to as oncogenic immune signaling states. Through gene expression analyses and functional genetic studies, we found that the ubiquitin (Ub) conjugating enzyme UBE2N is required for leukemic cell function in vitro and in vivo by maintaining oncogenic immune signaling states. Using newly identified small molecule inhibitors of UBE2N as chemical probes, we further revealed the therapeutic efficacy of interfering with UBE2N Ub-conjugating function by preventing ubiquitination of multiple innate immune- and inflammatory-related substrates in AML. Inhibition of UBE2N catalytic function in AML disrupted oncogenic immune signaling by promoting cell death of leukemic HSPCs while sparing healthy cells. Moreover, baseline oncogenic immune signaling states in discrete subsets of primary AML patients exhibited a selective dependency on UBE2N catalytic function. Our study reveals that interfering with UBE2N function abrogates leukemic HSPCs and underscores the dependency of AML cells on UBE2N-dependent oncogenic immune signaling states

2022-09-30 | GSE184852 | GEO

RNA sequencing MOLM-13 cells treated with the UBE2N inhibitor UC-764864 or DMSO control

Project description:Dysregulation of innate immune and inflammatory signaling pathways is implicated in various hematologic malignancies. Yet, these pathways have not been systematically examined in acute myeloid leukemia (AML). We report that AML hematopoietic stem and progenitor cells (HSPCs) exhibit a high frequency of dysregulated innate immune-related and inflammatory pathways, referred to as oncogenic immune signaling states. Through gene expression analyses and functional genetic studies, we found that the ubiquitin (Ub) conjugating enzyme UBE2N is required for leukemic cell function in vitro and in vivo by maintaining oncogenicimmune signaling states. Using newly identified small molecule inhibitors of UBE2N as chemical probes, we further revealed the therapeutic efficacy of interfering with UBE2N Ub-conjugating function by preventing ubiquitination of multiple innate immune- and inflammatory-related substrates in AML. Inhibition of UBE2N catalytic function in AML disrupted oncogenic immune signaling by promoting cell death of leukemic HSPCs while sparing healthy cells. Moreover, baseline oncogenic immune signaling states in discrete subsets of primary AML patients exhibited a selective dependency on UBE2N catalytic function. Our study reveals that interfering with UBE2N function abrogates leukemic HSPCs and underscores the dependency of AML cells on UBE2N-dependent oncogenic immune signaling states

2022-09-30 | GSE184889 | GEO

The UBA-domain of Ubc1/Ube2K Facilitates the Assembly of K48-/K63-Branched Ubiquitin Chains

Project description:Assembly of polymeric ubiquitin (Ub) chains is an essential posttranslational protein modification that regulates widespread intracellular processes in eukaryotic cells. Factors and mechanisms that regulate the formation of Ub chains are key to the understanding of many cellular processes. The E2 enzyme Ubc1 (Ube2K) exclusively targets K48 in Ub for chain formation and has been linked to cell-cycle progression and proteostasis. Uniquely among E2 enzymes, it harbors a Ub binding UBA domain, which has been implicated in Ub chain formation but its function remained elusive. Through in vitro binding experiments, we unexpectedly found that the UBA domain enables preferential binding of K63-linked Ub chains. Based on structural modeling, extensive in vitro ubiquitination experiments and NMR binding studies, we propose a mechanism through which Ubc1 selectively forms K48/K63 branched Ub chains – an usual chain architecture, about whose prevalence and function little is known to date. Ultimately, we link UBA dependent activity of Ubc1 to its role in proteostasis through genetic experiments.

2021-09-09 | PXD018651 | Pride

UbiREAD deciphers proteasomal degradation code of homotypic and branched K48 and K63 ubiquitin chains

Project description:Ubiquitin chains encode signals defining the fates of their modified proteins. Ubiquitin chain-mediated proteasomal degradation is a widespread eukaryotic regulatory mechanism. Yet, heterogeneity of intracellular ubiquitination has precluded systematically comparing degradation capacities of different ubiquitin chains. Here, we monitor cellular degradation and deubiquitination at high temporal resolution after delivery of bespoke ubiquitinated proteins into human cells. Comparing degradation of a model substrate modified with various K48, K63 or K48/K63-branched ubiquitin chains revealed fundamental differences in their intracellular degradation capacities. K48 chains with three or more ubiquitins triggered degradation within minutes. K63-ubiquitinated substrate was rapidly deubiquitinated rather than degraded. Surprisingly, degradation and deubiquitination behaviour of K48/K63-branched chains was determined by the identity of the substrate-anchored chain, establishing that branched chains are not the sum of their parts. Overall, our work reveals a degradation code for ubiquitin chains varying by linkage, length and topology and a functional hierarchy within branched ubiquitin chains.

2025-06-23 | PXD060731 | Pride

Enhancement of ubiquitination-dependent mitophagy by unconventionally-acting PROTACs

Project description:Enhancing mitophagy, a naturally-occurring cellular process for elimination of damaged mitochondria, holds great promise for the intervention of many human diseases. Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules that induce ubiquitination and subsequent proteasome-mediated degradation of a target protein through simultaneously binding to the target protein and an E3 ubiquitin ligase. However, the narrow cavity of the proteasome prevents the degradation of mitochondria. Here we show that the E3 ubiquitin ligase MAP3K1, when recruited to the outer mitochondria membrane (OMM) protein TSPO by our PROTAC-designed molecules (termed “mitophagy-enhancing chimeras”, or MECs), induced extensive K63 ubiquitination of TSPO and other OMM proteins, reminiscent of the PINK1-activated Parkin, without triggering proteasome-mediated degradation of TSPO. Aided by NBR1 and Nur77, this increased K63 ubiquitination of OMM proteins triggered mitophagy exclusively for damaged mitochondria, leading to improved mitochondria function and diminished cellular ROS. With the capability to enhance mitophagy at low nanomolar concentrations, MECs effectively inhibited NLRP3 inflammasome activation, abrogated acetaminophen-induced acute liver injury and mitigated high-fat diet-induced obesity in mice. Our work provided a proof-of-concept for developing unconventionally-acting PROTACs to achieve degradation of damaged mitochondria and possibly other organelles.

2024-02-08 | GSE255354 | GEO

Modulation of proteostasis by the ubiquitin-conjugating enzyme UBE2N in immunoproteasome-positive AML

Project description:Modulation of proteostasis by the ubiquitin-conjugating enzyme UBE2N in immunoproteasome-positive AML

| PRJNA1207531 | ENA

Cancer-cell-secreted miR-122 suppresses O-GlcNAcylation to promote muscle proteolysis

Project description:Decline in skeletal muscle mass and lower muscular strength are prognostic factors in advanced human cancers. We found that breast cancer suppressed O-linked N-acetylglucosamine (O-GlcNAc) protein modification in skeletal muscle through extracellular-vesicle-encapsulated miR-122 that targeted O-GlcNAc transferase (OGT). Specifically, O-GlcNAcylation of ryanodine receptor 1 (RYR1) Ca2+ release channel competed with NEK10-mediated phosphorylation and increased K48-linked ubiquitination and proteasomal degradation, whereas O-GlcNAcylation of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA3) increased K63-linked ubiquitination and elevated protein level. Muscular protein O-GlcNAcylation was regulated by hypoxia and lactate through HIF1A-dependent OGT promoter activation, and elevated after exercise. Suppressed O-GlcNAcylation in the setting of cancer, especially through increased RYR1 protein, led to Ca2+ leak and calpain protease activation to trigger myofibrillar protein cleavage. This was associated with reduced skeletal muscle mass and contractility in tumor-bearing mice. Our findings link O-GlcNAcylation to muscular protein homeostasis and contractility, and reveal a mechanism of cancer-associated muscle dysregulation.

2023-03-10 | PXD021232 | Pride

Analysis of ubiquitination sites in Neh2Dual-sGFP substrate

Project description:Determination of ubiquitination sites on an artificial substrate consisting of an Neh2 domain from Nrf2 that has been modified to be able to be ubiquitinated with three different E3 ligase systems, Ubr1 (which forms K48 linkages), Rsp5 (which forms K63 linkages) and Cul3/Rbx1/Keap1 (which forms branched linkages).

2024-01-05 | MSV000093780 | MassIVE

Ubiquitination profile of polarized macrophages

Project description:Previous studies linked mac activation with the ubiquitination (ub) status of key proteins in inflammatory signal pathways. Lysine-48 ub (K48-ub) of the NF-κB inhibitor (IκB), the final checkpoint of the NFκB pathway, leads to IκB degradation and consequent NF-κB-associated inflammation. In contrast, TRAF6, an upstream positive regulator of the NF-κB pathway, is modulated by K63-ub, leading to its conformational change and activation. However, a comprehensive analysis of ub profiles of polarized macs has not been reported. If a unique ub signature is associated with individual mac subsets is not known.

2020-08-06 | PXD018743 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data