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1.
Urolithiasis ; 52(1): 55, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564006

RESUMO

The formation of calcium oxalate (CaOx) crystals in the kidneys leads to renal epithelial damage and the progression of crystalline nephropathy. This study investigated the role of STIP1 homology and U-box protein 1 (STUB1), an E3 ubiquitin ligase, and cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel, in CaOx-related renal damage and autophagy regulation. HK-2 cells were treated with various doses of CaOx monohydrate (COM) to simulate kidney injury in vitro. Cell viability, reactive oxygen species (ROS) production, and apoptosis were assessed. The regulation of CFTR ubiquitination by STUB1 was confirmed by immunoprecipitation. An in vivo model was established by injecting mice with glyoxylate. COM treatment dose-dependently decreased cell viability, increased TNF-α and ROS production, and induced apoptotic cell death in HK-2 cells. COM-treated cells also showed decreased CFTR protein expression. CFTR overexpression improved cell viability and reduced ROS production in COM-stimulated HK-2 cells. Bioinformatics analysis predicted CFTR's ubiquitination binding site for STUB1. Further analysis confirmed the role of STUB1 as a ubiquitin ligase in CFTR degradation. Knockdown of STUB1 upregulated CFTR expression, while STUB1 overexpression had the opposite effect. Knockdown of CFTR reversed the impact of STUB1 deficiency on autophagy. The in vivo experiments showed that CFTR overexpression attenuated kidney tissue damage and CaOx deposition in mice. STUB1-mediated CFTR ubiquitination plays a crucial role in mitigating calcium oxalate-related renal damage by regulating autophagy. Targeting the STUB1/CFTR axis may hold therapeutic potential for treating kidney injury associated with calcium oxalate deposition.


Assuntos
Oxalato de Cálcio , Regulador de Condutância Transmembrana em Fibrose Cística , Animais , Camundongos , Espécies Reativas de Oxigênio , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Rim , Autofagia , Ubiquitinação , Oxalatos
2.
Biochem J ; 481(7): 515-545, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38572758

RESUMO

Maintaining stability of the genome requires dedicated DNA repair and signalling processes that are essential for the faithful duplication and propagation of chromosomes. These DNA damage response (DDR) mechanisms counteract the potentially mutagenic impact of daily genotoxic stresses from both exogenous and endogenous sources. Inherent to these DNA repair pathways is the activity of protein factors that instigate repair processes in response to DNA lesions. The regulation, coordination, and orchestration of these DDR factors is carried out, in a large part, by post-translational modifications, such as phosphorylation, ubiquitylation, and modification with ubiquitin-like proteins (UBLs). The importance of ubiquitylation and UBLylation with SUMO in DNA repair is well established, with the modified targets and downstream signalling consequences relatively well characterised. However, the role of dedicated erasers for ubiquitin and UBLs, known as deubiquitylases (DUBs) and ubiquitin-like proteases (ULPs) respectively, in genome stability is less well established, particularly for emerging UBLs such as ISG15 and UFM1. In this review, we provide an overview of the known regulatory roles and mechanisms of DUBs and ULPs involved in genome stability pathways. Expanding our understanding of the molecular agents and mechanisms underlying the removal of ubiquitin and UBL modifications will be fundamental for progressing our knowledge of the DDR and likely provide new therapeutic avenues for relevant human diseases, such as cancer.


Assuntos
Peptídeo Hidrolases , Ubiquitina , Humanos , Ubiquitina/genética , Ubiquitina/metabolismo , Peptídeo Hidrolases/metabolismo , Ubiquitinação , Processamento de Proteína Pós-Traducional , Ubiquitinas/genética , Ubiquitinas/metabolismo , Dano ao DNA , Endopeptidases/metabolismo , Instabilidade Genômica
3.
Nat Commun ; 15(1): 2974, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582895

RESUMO

Linear ubiquitination catalyzed by HOIL-1-interacting protein (HOIP), the key component of the linear ubiquitination assembly complex, plays fundamental roles in tissue homeostasis by executing domain-specific regulatory functions. However, a proteome-wide analysis of the domain-specific interactome of HOIP across tissues is lacking. Here, we present a comprehensive mass spectrometry-based interactome profiling of four HOIP domains in nine mouse tissues. The interaction dataset provides a high-quality HOIP interactome resource with an average of approximately 90 interactors for each bait per tissue. HOIP tissue interactome presents a systematic understanding of linear ubiquitination functions in each tissue and also shows associations of tissue functions to genetic diseases. HOIP domain interactome characterizes a set of previously undefined linear ubiquitinated substrates and elucidates the cross-talk among HOIP domains in physiological and pathological processes. Moreover, we show that linear ubiquitination of Integrin-linked protein kinase (ILK) decreases focal adhesion formation and promotes the detachment of Shigella flexneri-infected cells. Meanwhile, Hoip deficiency decreases the linear ubiquitination of Smad ubiquitination regulatory factor 1 (SMURF1) and enhances its E3 activity, finally causing a reduced bone mass phenotype in mice. Overall, our work expands the knowledge of HOIP-interacting proteins and provides a platform for further discovery of linear ubiquitination functions in tissue homeostasis.


Assuntos
Ubiquitina-Proteína Ligases , Ubiquitina , Animais , Camundongos , Homeostase , NF-kappa B/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
5.
Cell Commun Signal ; 22(1): 222, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594767

RESUMO

Csn5 is subunit 5 of the COP9 signalosome (CSN), but the mechanism by which it strictly controls the pathogenicity of pathogenic fungi through autophagy remains unclear. Here, we found that Csn5 deficiency attenuated pathogenicity and enhanced autophagy in Magnaporthe oryzae. MoCSN5 knockout led to overubiquitination and overdegradation of MoTor (the core protein of the TORC1 complex [target of rapamycin]) thereby promoted autophagy. In addition, we identified MoCsn5 as a new interactor of MoAtg6. Atg6 was found to be ubiquitinated through linkage with lysine 48 (K48) in cells, which is necessary for infection-associated autophagy in pathogenic fungi. K48-ubiquitination of Atg6 enhanced its degradation and thereby inhibited autophagic activity. Our experimental results indicated that MoCsn5 promoted K48-ubiquitination of MoAtg6, which reduced the MoAtg6 protein content and thus inhibited autophagy. Aberrant ubiquitination and autophagy in ΔMocsn5 led to pleiotropic defects in the growth, development, stress resistance, and pathogenicity of M. oryzae. In summary, our study revealed a novel mechanism by which Csn5 regulates autophagy and pathogenicity in rice blast fungus through ubiquitination.


Assuntos
Ascomicetos , Virulência , Proteínas , Ubiquitinação , Autofagia
6.
Sci Rep ; 14(1): 7997, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580756

RESUMO

Hepatocellular carcinoma (HCC) is characterized by high incidence and fatality rates worldwide. In our exploration of prognostic factors in HCC, the 26s proteasome subunit, non-ATPase 1 (PSMD1) protein emerged as a significant contributor, demonstrating its potential as a therapeutic target in this aggressive cancer. PSMD1 is a subunit of the 19S regulatory particle in the 26S proteasome complex; the 19S particle controls the deubiquitination of ubiquitinated proteins, which are then degraded by the proteolytic activity of the complex. Proteasome-targeting in cancer therapy has received significant attention because of its practical application as an established anticancer agent. We investigated whether PSMD1 plays a critical role in cancer owing to its prognostic significance. PSMD1 depletion induced cell cycle arrest in G2/M phase, DNA damage and apoptosis of cancer cells, irrespective of the p53 status. PSMD1 depletion-mediated cell death was accompanied by an increase in overall protein ubiquitination. These phenotypes occurred exclusively in cancer cells, with no effects observed in normal cells. These findings indicate that PSMD1 depletion-mediated ubiquitination of cellular proteins induces cell cycle arrest and eventual death in cancer cells, emphasizing PSMD1 as a potential therapeutic target in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Apoptose/genética , Carcinoma Hepatocelular/genética , Dano ao DNA , Neoplasias Hepáticas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação
7.
Front Immunol ; 15: 1359933, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562929

RESUMO

T cells play critical role in multiple immune processes including antigen response, tumor immunity, inflammation, self-tolerance maintenance and autoimmune diseases et. Fetal liver or bone marrow-derived thymus-seeding progenitors (TSPs) settle in thymus and undergo T cell-lineage commitment, proliferation, T cell receptor (TCR) rearrangement, and thymic selections driven by microenvironment composed of thymic epithelial cells (TEC), dendritic cells (DC), macrophage and B cells, thus generating T cells with diverse TCR repertoire immunocompetent but not self-reactive. Additionally, some self-reactive thymocytes give rise to Treg with the help of TEC and DC, serving for immune tolerance. The sequential proliferation, cell fate decision, and selection during T cell development and self-tolerance establishment are tightly regulated to ensure the proper immune response without autoimmune reaction. There are remarkable progresses in understanding of the regulatory mechanisms regarding ubiquitination in T cell development and the establishment of self-tolerance in the past few years, which holds great potential for further therapeutic interventions in immune-related diseases.


Assuntos
Doenças Autoimunes , Humanos , Doenças Autoimunes/metabolismo , Timo , Timócitos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Ubiquitinação
8.
J Environ Pathol Toxicol Oncol ; 43(3): 69-80, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38608146

RESUMO

The present study explored that the effects and its possible mechanisms of ring finger protein 20 (RNF20) in Postoperative survival rate of liver cancer in clinical. All the serum samples were collected from our hospital. Quantitative polymerase chain reaction (PCR) and microarray analysis, and RNA pull down assay were used in this study. We found that the serum RNF20 mRNA expression level in patients with liver cancer were down-regulated. Postoperative survival rate of RNF20 high expression was higher than that of RNF20 low expression. Then, over-expression of RNF20 diminished liver cancer cell proliferation and metastasis. RNF20 reduced Warburg effect of liver cancer. RNF20 expression regulated NOD-like receptor protein 3 (NLRP3) expression and increased NLRP3 Ubiquitination. NLRP3 participated in the effects of RNF20 on cell proliferation, and not affected on Warburg effect of liver cancer. Our study demonstrated that the serum RNF20 expression level was down-regulated in liver cancer, and promoted postoperative survival rate. RNF20 can reduce cancer progression of liver cancer by NLRP3 signal pathway, suggesting that it may prove to be a potential therapeutic target for postoperative survival rate of liver cancer.


Assuntos
Neoplasias Hepáticas , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Proliferação de Células , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas NLR , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
9.
Cell Death Dis ; 15(4): 241, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561375

RESUMO

Soft-tissue sarcomas (STS) emerges as formidable challenges in clinics due to the complex genetic heterogeneity, high rates of local recurrence and metastasis. Exploring specific targets and biomarkers would benefit the prognosis and treatment of STS. Here, we identified RCC1, a guanine-nucleotide exchange factor for Ran, as an oncogene and a potential intervention target in STS. Bioinformatics analysis indicated that RCC1 is highly expressed and correlated with poor prognosis in STS. Functional studies showed that RCC1 knockdown significantly inhibited the cell cycle transition, proliferation and migration of STS cells in vitro, and the growth of STS xenografts in mice. Mechanistically, we identified Skp2 as a downstream target of RCC1 in STS. Loss of RCC1 substantially diminished Skp2 abundance by compromising its protein stability, resulting in the upregulation of p27Kip1 and G1/S transition arrest. Specifically, RCC1 might facilitate the nucleo-cytoplasmic trafficking of Skp2 via direct interaction. As a result, the cytoplasmic retention of Skp2 would further protect it from ubiquitination and degradation. Notably, recovery of Skp2 expression largely reversed the phenotypes induced by RCC1 knockdown in STS cells. Collectively, this study unveils a novel RCC1-Skp2-p27Kip1 axis in STS oncogenesis, which holds promise for improving prognosis and treatment of this formidable malignancy.


Assuntos
Sarcoma , Animais , Humanos , Camundongos , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Sarcoma/genética , Sarcoma/patologia , Ubiquitinação , Regulação para Cima
10.
Commun Biol ; 7(1): 396, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561411

RESUMO

Myocardial ischemia-reperfusion injury (MIRI) is involved in the pathogenesis of multiple cardiovascular diseases. This study elucidated the biological function of lysine acetyltransferase 5 (KAT5) in cardiomyocyte pyroptosis during MIRI. Oxygen-glucose deprivation/reoxygenation and left anterior descending coronary artery ligation were used to establish MIRI models. Here we show, KAT5 and STIP1 homology and U-box-containing protein 1 (STUB1) were downregulated, while large tumor suppressor kinase 2 (LATS2) was upregulated in MIRI models. KAT5/STUB1 overexpression or LATS2 silencing repressed cardiomyocyte pyroptosis. Mechanistically, KAT5 promoted STUB1 transcription via acetylation modulation, and subsequently caused ubiquitination and degradation of LATS2, which activated YAP/ß-catenin pathway. Notably, the inhibitory effect of STUB1 overexpression on cardiomyocyte pyroptosis was abolished by LATS2 overexpression or KAT5 depletion. Our findings suggest that KAT5 overexpression inhibits NLRP3-mediated cardiomyocyte pyroptosis to relieve MIRI through modulation of STUB1/LATS2/YAP/ß-catenin axis, providing a potential therapeutic target for MIRI.


Assuntos
Traumatismo por Reperfusão Miocárdica , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Piroptose , Ubiquitinação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Lisina Acetiltransferase 5/metabolismo
11.
Cell Commun Signal ; 22(1): 213, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566235

RESUMO

BACKGROUND: Desensitization of G protein-coupled receptors (GPCRs) refers to the attenuation of receptor responsiveness by prolonged or intermittent exposure to agonists. The binding of ß-arrestin to the cytoplasmic cavity of the phosphorylated receptor, which competes with the G protein, has been widely accepted as an extensive model for explaining GPCRs desensitization. However, studies on various GPCRs, including dopamine D2-like receptors (D2R, D3R, D4R), have suggested the existence of other desensitization mechanisms. The present study employed D2R/D3R variants with different desensitization properties and utilized loss-of-function approaches to uncover the mechanisms underlying GPCRs homologous desensitization, focusing on the signaling cascade that regulates the ubiquitination of AKT. RESULTS: AKT undergoes K8/14 ubiquitination by TRAF6, which occurs in the nucleus and promotes its membrane recruitment, phosphorylation and activation under receptor desensitization conditions. The nuclear entry of TRAF6 relies on the presence of the importin complex. Src regulates the nuclear entry of TRAF6 by mediating the interaction between TRAF6 and importin ß1. Ubiquitinated AKT translocates to the plasma membrane where it associates with Mdm2 to phosphorylate it at the S166 and S186 residues. Thereafter, phosphorylated Mdm2 is recruited to the nucleus, resulting in the deubiquitination of ß-Arr2. The deubiquitinated ß-Arr2 then forms a complex with Gßγ, which serves as a biomarker for GPCRs desensitization. Like in D3R, ubiquitination of AKT is also involved in the desensitization of ß2 adrenoceptors. CONCLUSION: Our study proposed that the property of a receptor that causes a change in the subcellular localization of TRAF6 from the cytoplasm to the nucleus to mediate AKT ubiquitination could initiate the desensitization of GPCRs.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Fator 6 Associado a Receptor de TNF , Fator 6 Associado a Receptor de TNF/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Ubiquitinação , Fosforilação , Carioferinas
12.
Biochem Soc Trans ; 52(2): 627-637, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38572966

RESUMO

Functional consequences of protein ubiquitination have gone far beyond the degradation regulation as was initially imagined during its discovery 40 years back. The state-of-the-art has revealed the plethora of signaling pathways that are largely regulated by ubiquitination process in eukaryotes. To no surprise, ubiquitination is often dysregulated in many human diseases, including cancer, neurodegeneration and infection. Hence it has become a major focus with high-gain research value for many investigators to unravel new proteoforms, that are the targets of this ubiquitination modification. Despite many biochemical or proteomic approaches available for ubiquitination detection, mass-spectrometry stood out to be the most efficient and transformative technology to read this complex modification script. Here in this review, we have discussed how different ubiquitin codes can be decoded qualitatively and quantitatively following various sequential proteomic approaches to date reported and indicated the current limitations with scope for improvements.


Assuntos
Proteômica , Ubiquitina , Ubiquitinação , Humanos , Ubiquitina/metabolismo , Proteômica/métodos , Espectrometria de Massas/métodos , Animais , Transdução de Sinais
13.
Virus Res ; 344: 199368, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38588924

RESUMO

Several viruses are now known to code for deubiquitinating proteases in their genomes. Ubiquitination is an essential post-translational modification of cellular substrates involved in many processes in the cell, including in innate immune signalling. This post-translational modification is regulated by the ubiquitin conjugation machinery, as well as various host deubiquitinating enzymes. The conjugation of ubiquitin chains to several innate immune related factors is often needed to induce downstream signalling, shaping the antiviral response. Viral deubiquitinating proteins, besides often having a primary function in the viral replication cycle by cleaving the viral polyprotein, are also able to cleave ubiquitin chains from such host substrates, in that way exerting a function in innate immune evasion. The presence of viral deubiquitinating enzymes has been firmly established for numerous animal-infecting viruses, such as some well-researched and clinically important nidoviruses, and their presence has now been confirmed in several plant viruses as well. Viral proteases in general have long been highlighted as promising drug targets, with a current focus on small molecule inhibitors. In this review, we will discuss the range of viral deubiquitinating proteases known to date, summarise the various avenues explored to inhibit such proteases and discuss novel strategies and models intended to inhibit and study these specific viral enzymes.


Assuntos
Enzimas Desubiquitinantes , Enzimas Desubiquitinantes/metabolismo , Enzimas Desubiquitinantes/antagonistas & inibidores , Enzimas Desubiquitinantes/genética , Humanos , Proteases Virais/metabolismo , Processamento de Proteína Pós-Traducional , Ubiquitinação , Animais , Replicação Viral , Antivirais/farmacologia , Inibidores de Proteases/farmacologia , Vírus/efeitos dos fármacos , Vírus/enzimologia , Proteínas Virais/metabolismo , Proteínas Virais/genética , Ubiquitina/metabolismo , Imunidade Inata
14.
Sci Signal ; 17(831): eadg7867, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593156

RESUMO

Type I interferons (IFNs) are critical for the antiviral immune response, and fine-tuning type I IFN production is critical to effectively clearing viruses without causing harmful immunopathology. We showed that the transcription factor Miz1 epigenetically repressed the expression of genes encoding type I IFNs in mouse lung epithelial cells by recruiting histone deacetylase 1 (HDAC1) to the promoters of Ifna and Ifnb. Loss of function of Miz1 resulted in augmented production of these type I IFNs during influenza A virus (IAV) infection, leading to improved viral clearance in vitro and in vivo. IAV infection induced Miz1 accumulation by promoting the cullin-4B (CUL4B)-mediated ubiquitylation and degradation of the E3 ubiquitin ligase Mule (Mcl-1 ubiquitin ligase E3; also known as Huwe1 or Arf-BP1), which targets Miz1 for degradation. As a result, Miz1 accumulation limited type I IFN production and favored viral replication. This study reveals a previously unrecognized function of Miz1 in regulating antiviral defense and a potential mechanism for influenza viruses to evade host immune defense.


Assuntos
Vírus da Influenza A , Influenza Humana , Interferon Tipo I , Camundongos , Animais , Humanos , Vírus da Influenza A/fisiologia , Ubiquitinação , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Replicação Viral , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Influenza Humana/genética , Interferons/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Inibidoras de STAT Ativados/genética , Proteínas Inibidoras de STAT Ativados/metabolismo
15.
Learn Mem ; 31(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38580378

RESUMO

Posttranslational modification of histone proteins is critical for memory formation. Recently, we showed that monoubiquitination of histone H2B at lysine 120 (H2Bub) is critical for memory formation in the hippocampus. However, the transcriptome controlled by H2Bub remains unknown. Here, we found that fear conditioning in male rats increased or decreased the expression of 86 genes in the hippocampus but, surprisingly, siRNA-mediated knockdown of the H2Bub ligase, Rnf20, abolished changes in all but one of these genes. These findings suggest that monoubiquitination of histone H2B is a crucial regulator of the transcriptome during memory formation.


Assuntos
Histonas , Memória , Transcriptoma , Ubiquitinação , Animais , Masculino , Ratos , Histonas/genética , Processamento de Proteína Pós-Traducional , Transcriptoma/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
16.
Proc Natl Acad Sci U S A ; 121(17): e2315018121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38625940

RESUMO

Heterotrimeric G proteins can be regulated by posttranslational modifications, including ubiquitylation. KCTD5, a pentameric substrate receptor protein consisting of an N-terminal BTB domain and a C-terminal domain, engages CUL3 to form the central scaffold of a cullin-RING E3 ligase complex (CRL3KCTD5) that ubiquitylates Gßγ and reduces Gßγ protein levels in cells. The cryo-EM structure of a 5:5:5 KCTD5/CUL3NTD/Gß1γ2 assembly reveals a highly dynamic complex with rotations of over 60° between the KCTD5BTB/CUL3NTD and KCTD5CTD/Gßγ moieties of the structure. CRL3KCTD5 engages the E3 ligase ARIH1 to ubiquitylate Gßγ in an E3-E3 superassembly, and extension of the structure to include full-length CUL3 with RBX1 and an ARIH1~ubiquitin conjugate reveals that some conformational states position the ARIH1~ubiquitin thioester bond to within 10 Å of lysine-23 of Gß and likely represent priming complexes. Most previously described CRL/substrate structures have consisted of monovalent complexes and have involved flexible peptide substrates. The structure of the KCTD5/CUL3NTD/Gßγ complex shows that the oligomerization of a substrate receptor can generate a polyvalent E3 ligase complex and that the internal dynamics of the substrate receptor can position a structured target for ubiquitylation in a CRL3 complex.


Assuntos
Proteínas de Transporte , Ubiquitina-Proteína Ligases , Ligação Proteica , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Transporte/metabolismo , Ubiquitina/metabolismo , Proteínas Culina/genética , Proteínas Culina/metabolismo
17.
Cell Death Dis ; 15(4): 274, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632244

RESUMO

Accumulating evidence demonstrates that the activity regulation of ELK3, a member of the E26 transformation-specific oncogene family, is critical to regulating cell proliferation, migration, and survival in human cancers. However, the molecular mechanisms of how ELK3 induces chemoresistance in prostate cancer (PCa) have not been elucidated. In this study, we found that SPOP and ELK3 are an interacting partner. The interaction between SPOP and ELK3 resulted in increased ELK3 ubiquitination and destruction, assisted by checkpoint kinase-mediated ELK3 phosphorylation. Notably, the modulation of SPOP-mediated ELK3 protein stability affected the c-Fos-induced cell proliferation and invasion of PCa cells. The clinical involvement of the SPOP-ELK3 axis in PCa development was confirmed by an immunohistochemical assay on 123 PCa tissues, with an inverse correlation between increased ELK3 and decreased SPOP being present in ~80% of the specimens. This observation was supported by immunohistochemistry analysis using a SPOP-mutant PCa specimen. Finally, docetaxel treatment induced cell death by activating checkpoint kinase- and SPOP-mediated ELK3 degradation, while SPOP-depleted or SPOP-mutated PCa cells showed cell death resistance. Notably, this observation was correlated with the protein levels of ELK3. Taken together, our study reveals the precise mechanism of SPOP-mediated degradation of ELK3 and provides evidence that SPOP mutations contribute to docetaxel resistance in PCa.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Docetaxel , Neoplasias da Próstata/genética , Próstata/metabolismo , Ubiquitinação , Proteínas Proto-Oncogênicas c-fos/metabolismo , Mutação , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo
18.
CNS Neurosci Ther ; 30(4): e14685, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634270

RESUMO

OBJECTIVE: Neuronal precursor cells expressed developmentally down-regulated 4 (Nedd4) are believed to play a critical role in promoting the degradation of substrate proteins and are involved in numerous biological processes. However, the role of Nedd4 in intracerebral hemorrhage (ICH) remains unknown. This study aims to investigate the regulatory role of Nedd4 in the ICH model. METHODS: Male C57BL/6J mice were induced with ICH. Subsequently, the levels of glutathione peroxidase 4 (GPX4), malondialdehyde (MDA) concentration, iron content, mitochondrial morphology, as well as the expression of divalent metal transporter 1 (DMT1) and Nedd4 were assessed after ICH. Furthermore, the impact of Nedd4 overexpression was evaluated through analyses of hematoma area, ferroptosis, and neurobehavioral function. The mechanism underlying Nedd4-mediated degradation of DMT1 was elecidated using immunoprecipitation (IP) after ICH. RESULTS: Upon ICH, the level of DMT1 in the brain increased, but decreased when Nedd4 was overexpressed using Lentivirus, suggesting a negative correlation between Nedd4 and DMT1. Additionally, the degradation of DMT1 was inhibited after ICH. Furthermore, it was found that Nedd4 can interact with and ubiquitinate DMT1 at lysine residues 6, 69, and 277, facilitating the degradation of DMT1. Functional analysis indicated that overexpression of Nedd4 can alleviate ferroptosis and promote recovery following ICH. CONCLUSION: The results demonstrated that ferroptosis occurs via the Nedd4/DMT1 pathway during ICH, suggesting it potential as a valuable target to inhibit ferroptosis for the treatment of ICH.


Assuntos
Ferroptose , Camundongos , Animais , Masculino , Camundongos Endogâmicos C57BL , Hemorragia Cerebral/metabolismo , Ubiquitinação , Encéfalo/metabolismo
19.
CNS Neurosci Ther ; 30(4): e14711, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644551

RESUMO

OBJECTIVE: To elucidate the relationship between USP19 and O(6)-methylguanine-DNA methyltransferase (MGMT) after temozolomide treatment in glioblastoma (GBM) patients with chemotherapy resistance. METHODS: Screening the deubiquitinase pannel and identifying the deubiquitinase directly interacts with and deubiquitination MGMT. Deubiquitination assay to confirm USP19 deubiquitinates MGMT. The colony formation and tumor growth study in xenograft assess USP19 affects the GBM sensitive to TMZ was performed by T98G, LN18, U251, and U87 cell lines. Immunohistochemistry staining and survival analysis were performed to explore how USP19 is correlated to MGMT in GBM clinical management. RESULTS: USP19 removes the ubiquitination of MGMT to facilitate the DNA methylation damage repair. Depletion of USP19 results in the glioblastoma cell sensitivity to temozolomide, which can be rescued by overexpressing MGMT. USP19 is overexpressed in glioblastoma patient samples, which positively correlates with the level of MGMT protein and poor prognosis in these patients. CONCLUSION: The regulation of MGMT ubiquitination by USP19 plays a critical role in DNA methylation damage repair and GBM patients' temozolomide chemotherapy response.


Assuntos
Antineoplásicos Alquilantes , Metilação de DNA , Metilases de Modificação do DNA , Enzimas Reparadoras do DNA , Resistencia a Medicamentos Antineoplásicos , Temozolomida , Proteínas Supressoras de Tumor , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Enzimas Reparadoras do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Metilases de Modificação do DNA/metabolismo , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Animais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Metilação de DNA/efeitos dos fármacos , Camundongos Nus , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Camundongos , Masculino , Feminino , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Reparo do DNA/efeitos dos fármacos , Endopeptidases/metabolismo , Endopeptidases/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Ubiquitinação/efeitos dos fármacos
20.
Theranostics ; 14(6): 2345-2366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646645

RESUMO

Rationale: Primordial follicles are limited in number and cannot be regenerated, dormant primordial follicles cannot be reversed once they enter a growth state. Therefore, the length of the female reproductive lifespan depends on the orderly progression and selective activation of primordial follicles, the mechanism of which remains unclear. Methods: We used human ovarian cortical biopsy specimens, granulosa cells from diminished ovarian reserve (DOR) patients, Hdac6-overexpressing transgenic mouse model, and RNA sequencing to analyze the crucial roles of histone deacetylase 6 (HDAC6) in fertility preservation and primordial follicle activation. Results: In the present study, we found that HDAC6 was highly expressed in most dormant primordial follicles. The HDAC6 expression was reduced accompanying reproductive senescence in human and mouse ovaries. Overexpression of Hdac6 delayed the rate of primordial follicle activation, thereby prolonging the mouse reproductive lifespan. Short-term inhibition of HDAC6 promoted primordial follicle activation and follicular development in humans and mice. Mechanism studies revealed that HDAC6 directly interacted with NGF, reducing acetylation modification of NGF and thereby accelerating its ubiquitination degradation. Consequently, the reduced NGF protein level maintained the dormancy of primordial follicles. Conclusions: The physiological significance of the high expression of HDAC6 in most primordial follicles is to reduce NGF expression and prevent primordial follicle activation to maintain female fertility. Reduced HDAC6 expression increases NGF expression in primordial follicles, activating their development and contributing to reproduction. Our study provides a clinical reference value for fertility preservation.


Assuntos
Desacetilase 6 de Histona , Camundongos Transgênicos , Fator de Crescimento Neural , Folículo Ovariano , Ubiquitinação , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/genética , Animais , Feminino , Folículo Ovariano/metabolismo , Humanos , Camundongos , Acetilação , Fator de Crescimento Neural/metabolismo , Células da Granulosa/metabolismo
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