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1.
Int J Biol Macromol ; 277(Pt 4): 134390, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111466

RESUMO

Members of the KCTD protein family play key roles in fundamental physio-pathological processes including cancer, neurodevelopmental/neuropsychiatric, and genetic diseases. Here, we report the crystal structure of the KCTD1 P20S mutant, which causes the scalp-ear-nipple syndrome, and molecular dynamics (MD) data on the wild-type protein. Surprisingly, the structure unravels that the N-terminal region, which precedes the BTB domain (preBTB) and bears the disease-associated mutation, adopts a folded polyproline II (PPII) state. The KCTD1 pentamer is characterized by an intricate architecture in which the different subunits mutually exchange domains to generate a closed domain swapping motif. Indeed, the BTB of each chain makes peculiar contacts with the preBTB and the C-terminal domain (CTD) of an adjacent chain. The BTB-preBTB interaction consists of a PPII-PPII recognition motif whereas the BTB-CTD contacts are mediated by an unusual (+/-) helix discontinuous association. The inspection of the protein structure, along with the data emerged from the MD simulations, provides an explanation of the pathogenicity of the P20S mutation and unravels the role of the BTB-preBTB interaction in the insurgence of the disease. Finally, the presence of potassium bound to the central cavity of the CTD pentameric assembly provides insights into the role of KCTD1 in metal homeostasis.


Assuntos
Proteínas Correpressoras , Mutação , Humanos , Sequência de Aminoácidos , Proteínas Correpressoras/química , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Domínios Proteicos , Relação Estrutura-Atividade
2.
Nat Commun ; 15(1): 7534, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39214989

RESUMO

The human silencing hub (HUSH) complex binds to transcripts of LINE-1 retrotransposons (L1s) and other genomic repeats, recruiting MORC2 and other effectors to remodel chromatin. How HUSH and MORC2 operate alongside DNA methylation, a central epigenetic regulator of repeat transcription, remains largely unknown. Here we interrogate this relationship in human neural progenitor cells (hNPCs), a somatic model of brain development that tolerates removal of DNA methyltransferase DNMT1. Upon loss of MORC2 or HUSH subunit TASOR in hNPCs, L1s remain silenced by robust promoter methylation. However, genome demethylation and activation of evolutionarily-young L1s attracts MORC2 binding, and simultaneous depletion of DNMT1 and MORC2 causes massive accumulation of L1 transcripts. We identify the same mechanistic hierarchy at pericentromeric α-satellites and clustered protocadherin genes, repetitive elements important for chromosome structure and neurodevelopment respectively. Our data delineate the epigenetic control of repeats in somatic cells, with implications for understanding the vital functions of HUSH-MORC2 in hypomethylated contexts throughout human development.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA , Elementos Nucleotídeos Longos e Dispersos , Células-Tronco Neurais , Humanos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Células-Tronco Neurais/metabolismo , Elementos Nucleotídeos Longos e Dispersos/genética , Epigênese Genética , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Inativação Gênica , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proteínas do Tecido Nervoso
3.
Open Biol ; 14(7): 230355, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981515

RESUMO

Epigenetic regulation is important for circadian rhythm. In previous studies, multiple histone modifications were found at the Period (Per) locus. However, most of these studies were not conducted in clock neurons. In our screen, we found that a CoREST mutation resulted in defects in circadian rhythm by affecting Per transcription. Based on previous studies, we hypothesized that CoREST regulates circadian rhythm by regulating multiple histone modifiers at the Per locus. Genetic and physical interaction experiments supported these regulatory relationships. Moreover, through tissue-specific chromatin immunoprecipitation assays in clock neurons, we found that the CoREST mutation led to time-dependent changes in corresponding histone modifications at the Per locus. Finally, we proposed a model indicating the role of the CoREST complex in the regulation of circadian rhythm. This study revealed the dynamic changes of histone modifications at the Per locus specifically in clock neurons. Importantly, it provides insights into the role of epigenetic factors in the regulation of dynamic gene expression changes in circadian rhythm.


Assuntos
Ritmo Circadiano , Proteínas Correpressoras , Epigênese Genética , Neurônios , Proteínas Circadianas Period , Animais , Neurônios/metabolismo , Proteínas Circadianas Period/metabolismo , Proteínas Circadianas Period/genética , Camundongos , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Histonas/metabolismo , Código das Histonas , Mutação , Relógios Circadianos/genética , Regulação da Expressão Gênica
4.
Clin Immunol ; 266: 110326, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059757

RESUMO

The interferon regulatory factor 2 binding protein 2 (IRF2BP2) is a transcriptional regulator, functioning a transcriptional corepressor by interacting with the interferon regulatory factor-2. The ubiquitous expression of IRF2BP2 by diverse cell types and tissues suggests its potential involvement in different cell signalling pathways. Variants inIRF2BP2have been recently identified to cause familial common variable immunodeficiency (CVID) characterized by immune dysregulation. This study investigated three rare novel variants inIRF2BP2, identified in patients with primary antibody deficiency and autoimmunity by whole exome-sequencing (WES). Following transient overexpression of EGFP-fused mutants in HEK293 cells and transfection in Jurkat cell lines, we used fluorescence microscopy, real-time PCR and Western blotting to analyze their effects on IRF2BP2 expression, subcellular localization, nuclear translocation of IRF2, and the transcriptional activation of NFκB1(p50). We found altered IRF2BP2 mRNA and protein expression levels in the mutants compared to the wild type after IRF2BP2 overexpression. In confocal fluorescence microscopy, variants in the C-terminal RING finger domain showed an irregular aggregate formation and distribution instead of the expected nuclear localization compared to the variants in the N-terminal zinc finger domain and their wildtype counterpart. Immunoblotting revealed an impaired IRF2 and NFκB1 (p50) nuclear localization in the mutants compared to the IRF2BP2 wildtype counterpart. LPS stimulation reduced IRF2BP2 mRNA expression in the variants compared to the wild type. Our findings significantly contribute to understanding the clinical significance of IRF2BP2 mutations in the pathogenesis of immunodeficiency and immune dysregulation. We observed impairment of the nuclear translocation of IRF2 and NFκB1 (p50) due to the upregulation of IRF2BP2, potentially affecting specific gene expressions involved in immune regulation.


Assuntos
Autoimunidade , Imunodeficiência de Variável Comum , Humanos , Células HEK293 , Imunodeficiência de Variável Comum/genética , Imunodeficiência de Variável Comum/imunologia , Autoimunidade/genética , Células Jurkat , Fator Regulador 2 de Interferon/genética , Fator Regulador 2 de Interferon/metabolismo , Fator Regulador 2 de Interferon/imunologia , Masculino , Feminino , Mutação , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Sequenciamento do Exoma , Proteínas Correpressoras/genética , Proteínas de Ligação a DNA , Fatores de Transcrição
5.
Nat Commun ; 15(1): 5585, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992040

RESUMO

MYCN oncogene amplification is frequently observed in aggressive childhood neuroblastoma. Using an unbiased large-scale mutagenesis screen in neuroblastoma-prone transgenic mice, we identify a single germline point mutation in the transcriptional corepressor Runx1t1, which abolishes MYCN-driven tumorigenesis. This loss-of-function mutation disrupts a highly conserved zinc finger domain within Runx1t1. Deletion of one Runx1t1 allele in an independent Runx1t1 knockout mouse model is also sufficient to prevent MYCN-driven neuroblastoma development, and reverse ganglia hyperplasia, a known pre-requisite for tumorigenesis. Silencing RUNX1T1 in human neuroblastoma cells decreases colony formation in vitro, and inhibits tumor growth in vivo. Moreover, RUNX1T1 knockdown inhibits the viability of PAX3-FOXO1 fusion-driven rhabdomyosarcoma and MYC-driven small cell lung cancer cells. Despite the role of Runx1t1 in MYCN-driven tumorigenesis neither gene directly regulates the other. We show RUNX1T1 forms part of a transcriptional LSD1-CoREST3-HDAC repressive complex recruited by HAND2 to enhancer regions to regulate chromatin accessibility and cell-fate pathway genes.


Assuntos
Carcinogênese , Proteína Proto-Oncogênica N-Myc , Neuroblastoma , Animais , Humanos , Camundongos , Carcinogênese/genética , Linhagem Celular Tumoral , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Camundongos Knockout , Camundongos Transgênicos , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
6.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39000549

RESUMO

Synaptic ribbons are the eponymous specializations of continuously active ribbon synapses. They are primarily composed of the RIBEYE protein that consists of a unique amino-terminal A-domain and carboxy-terminal B-domain that is largely identical to the ubiquitously expressed transcriptional regulator protein CtBP2. Both RIBEYE A-domain and RIBEYE B-domain are essential for the assembly of the synaptic ribbon, as shown by previous analyses of RIBEYE knockout and knockin mice and related investigations. How exactly the synaptic ribbon is assembled from RIBEYE subunits is not yet clear. To achieve further insights into the architecture of the synaptic ribbon, we performed analytical post-embedding immunogold-electron microscopy with direct gold-labelled primary antibodies against RIBEYE A-domain and RIBEYE B-domain for improved ultrastructural resolution. With direct gold-labelled monoclonal antibodies against RIBEYE A-domain and RIBEYE B-domain, we found that both domains show a very similar localization within the synaptic ribbon of mouse photoreceptor synapses, with no obvious differential gradient between the centre and surface of the synaptic ribbon. These data favour a model of the architecture of the synaptic ribbon in which the RIBEYE A-domain and RIBEYE B-domain are located similar distances from the midline of the synaptic ribbon.


Assuntos
Anticorpos Monoclonais , Sinapses , Animais , Camundongos , Sinapses/ultraestrutura , Sinapses/metabolismo , Anticorpos Monoclonais/imunologia , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/química , Proteínas Correpressoras/metabolismo , Imuno-Histoquímica/métodos , Domínios Proteicos , Microscopia Imunoeletrônica/métodos , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/imunologia
7.
Nat Commun ; 15(1): 5241, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898011

RESUMO

While the elucidation of regulatory mechanisms of folded proteins is facilitated due to their amenability to high-resolution structural characterization, investigation of these mechanisms in disordered proteins is more challenging due to their structural heterogeneity, which can be captured by a variety of biophysical approaches. Here, we used the transcriptional master corepressor CtBP, which binds the putative metastasis suppressor RAI2 through repetitive SLiMs, as a model system. Using cryo-electron microscopy embedded in an integrative structural biology approach, we show that RAI2 unexpectedly induces CtBP polymerization through filaments of stacked tetrameric CtBP layers. These filaments lead to RAI2-mediated CtBP nuclear foci and relieve its corepressor function in RAI2-expressing cancer cells. The impact of RAI2-mediated CtBP loss-of-function is illustrated by the analysis of a diverse cohort of prostate cancer patients, which reveals a substantial decrease in RAI2 in advanced treatment-resistant cancer subtypes. As RAI2-like SLiM motifs are found in a wide range of organisms, including pathogenic viruses, our findings serve as a paradigm for diverse functional effects through multivalent interaction-mediated polymerization by disordered proteins in healthy and diseased conditions.


Assuntos
Oxirredutases do Álcool , Polimerização , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/química , Microscopia Crioeletrônica , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/química , Ligação Proteica , Células HEK293 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Motivos de Aminoácidos , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética
8.
Plant Sci ; 346: 112149, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38851591

RESUMO

TOPLESS/TOPLESS-RELATED (TPL/TPR) proteins belong to the Groucho (Gro)/Tup1 family co-repressors and act as broad co-repressors that modulate multiple phytohormone signalling pathways and various developmental processes in plant. However, TPL/TPR co-repressors so far are poorly understood in the rapeseed, one of the world-wide important oilseed crops. In this study, we comprehensively characterized eighteen TPL/TPR genes into five groups in the rapeseed genome. Members of TPL/TPR1/TPR4 and TPR2/TPR3 had close evolutionary relationship, respectively. All TPL/TPRs had similar expression patterns and encode conserved protein domain. In addition, we demonstrated that BnaA9.TPL interacted with all known plant repression domain (RD) sequences, which were distributed in non-redundant 24,238 (22.6 %) genes and significantly enriched in transcription factors in the rapeseed genome. These transcription factors were largely co-expressed with the TPL/TPR genes and involved in diverse pathway, including phytohormone signal transduction, protein kinases and circadian rhythm. Furthermore, BnaA9.TPL was revealed to regulate apical embryonic fate by interaction with Bna.IAA12 and suppression of PLETHORA1/2. BnaA9.TPL was also identified to regulate leaf morphology by interaction with Bna.AS1 (Asymmetric leaves 1) and suppression of KNOTTED-like homeobox genes and YABBY5. These data not only suggest the rapeseed TPL/TPRs play broad roles in different processes, but also provide useful information to uncover more TPL/TPR-mediated control of plant development in rapeseed.


Assuntos
Regulação da Expressão Gênica de Plantas , Folhas de Planta , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Estudo de Associação Genômica Ampla , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Filogenia , Genoma de Planta
9.
Hum Pathol ; 150: 51-57, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38909708

RESUMO

Pancreatic neuroendocrine tumors (PanNETs) comprise a heterogeneous group of neoplasms in terms of biological behavior. This study aims to develop a practical algorithm based on emerging biomarkers, including chromatin-remodeling molecules DAXX/ATRX/H3K36me3, in conjunction with established prognostic factors, such as WHO grade and size. In immunohistochemical analyses, 18 of the 111 (16.2%) primary PanNETs showed DAXX or ATRX loss in a mutually exclusive manner. DAXX/ATRX loss was significantly correlated with higher recurrence risk and better predicted postoperative recurrence than WHO grade. We proposed a novel algorithm for stratifying patients with resectable PanNET into three groups according to recurrence risk: (A) WHO Grade 1 and ≤2 cm (very low-risk); for the others, (B) retained DAXX/ATRX (low-risk) and (C) DAXX/ATRX complete/heterogeneous loss (high-risk). Furthermore, we elucidated the intratumoral heterogeneities of PanNETs. Among cases with DAXX or ATRX loss, nine cases demonstrated heterogeneous loss of expression of DAXX/ATRX/H3K36me3. The majority of cases with DAXX/ATRX loss, either homogeneous or heterogeneous loss, showed uniform α-cell-like phenotype (ARX1+/PDX1-). In cases of metastatic or recurrent tumors, the expression pattern was identical to that observed in at least part of the primary tumor. In some instances, the expression pattern differed among different metastatic or recurrent tumors of the same patient. In summary, we propose a clinically useful and practical algorithm for postoperative recurrence risk stratification in PanNETs, by combining DAXX/ATRX status with WHO grade and size. Moreover, our findings highlighted the frequent spatiotemporal heterogeneity of chromatin-remodeling molecule expression in PanNETs with an α-cell phenotype, offering insights into tumorigenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Biomarcadores Tumorais , Proteínas Correpressoras , Chaperonas Moleculares , Recidiva Local de Neoplasia , Tumores Neuroendócrinos , Proteínas Nucleares , Neoplasias Pancreáticas , Fenótipo , Proteína Nuclear Ligada ao X , Humanos , Proteína Nuclear Ligada ao X/análise , Neoplasias Pancreáticas/patologia , Masculino , Feminino , Recidiva Local de Neoplasia/patologia , Tumores Neuroendócrinos/patologia , Pessoa de Meia-Idade , Idoso , Proteínas Adaptadoras de Transdução de Sinal/análise , Biomarcadores Tumorais/análise , Proteínas Nucleares/análise , Adulto , Fatores de Risco , Imuno-Histoquímica , Algoritmos , Medição de Risco , Idoso de 80 Anos ou mais , Gradação de Tumores
10.
J Neuroinflammation ; 21(1): 143, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822367

RESUMO

The dysregulation of pro- and anti-inflammatory processes in the brain has been linked to the pathogenesis of major depressive disorder (MDD), although the precise mechanisms remain unclear. In this study, we discovered that microglial conditional knockout of Pdcd4 conferred protection against LPS-induced hyperactivation of microglia and depressive-like behavior in mice. Mechanically, microglial Pdcd4 plays a role in promoting neuroinflammatory responses triggered by LPS by inhibiting Daxx-mediated PPARγ nucleus translocation, leading to the suppression of anti-inflammatory cytokine IL-10 expression. Finally, the antidepressant effect of microglial Pdcd4 knockout under LPS-challenged conditions was abolished by intracerebroventricular injection of the IL-10 neutralizing antibody IL-10Rα. Our study elucidates the distinct involvement of microglial Pdcd4 in neuroinflammation, suggesting its potential as a therapeutic target for neuroinflammation-related depression.


Assuntos
Proteínas Correpressoras , Interleucina-10 , Camundongos Knockout , Microglia , Doenças Neuroinflamatórias , PPAR gama , Transdução de Sinais , Animais , Masculino , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/deficiência , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Depressão/metabolismo , Depressão/etiologia , Interleucina-10/metabolismo , Interleucina-10/deficiência , Interleucina-10/genética , Lipopolissacarídeos/toxicidade , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/efeitos dos fármacos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Doenças Neuroinflamatórias/metabolismo , PPAR gama/metabolismo , PPAR gama/genética , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos
11.
Biol Direct ; 19(1): 48, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902802

RESUMO

BACKGROUND: Prior research has highlighted the involvement of a transcriptional complex comprising C-terminal binding protein 2 (CtBP2), histone acetyltransferase p300, and nuclear factor kappa B (NF-κB) in the transactivation of proinflammatory cytokine genes, contributing to inflammation in mice with acute respiratory distress syndrome (ARDS). Nonetheless, it remains uncertain whether the therapeutic targeting of the CtBP2-p300-NF-κB complex holds potential for ARDS suppression. METHODS: An ARDS mouse model was established using lipopolysaccharide (LPS) exposure. RNA-Sequencing (RNA-Seq) was performed on ARDS mice and LPS-treated cells with CtBP2, p300, and p65 knockdown. Small molecules inhibiting the CtBP2-p300 interaction were identified through AlphaScreen. Gene and protein expression levels were quantified using RT-qPCR and immunoblots. Tissue damage was assessed via histological staining. KEY FINDINGS: We elucidated the specific role of the CtBP2-p300-NF-κB complex in proinflammatory gene regulation. RNA-seq analysis in LPS-challenged ARDS mice and LPS-treated CtBP2-knockdown (CtBP2KD), p300KD, and p65KD cells revealed its significant impact on proinflammatory genes with minimal effects on other NF-κB targets. Commercial inhibitors for CtBP2, p300, or NF-κB exhibited moderate cytotoxicity in vitro and in vivo, affecting both proinflammatory genes and other targets. We identified a potent inhibitor, PNSC928, for the CtBP2-p300 interaction using AlphaScreen. PNSC928 treatment hindered the assembly of the CtBP2-p300-NF-κB complex, substantially downregulating proinflammatory cytokine gene expression without observable cytotoxicity in normal cells. In vivo administration of PNSC928 significantly reduced CtBP2-driven proinflammatory gene expression in ARDS mice, alleviating inflammation and lung injury, ultimately improving ARDS prognosis. CONCLUSION: Our results position PNSC928 as a promising therapeutic candidate to specifically target the CtBP2-p300 interaction and mitigate inflammation in ARDS management.


Assuntos
Oxirredutases do Álcool , Proteína p300 Associada a E1A , Inflamação , Síndrome do Desconforto Respiratório , Animais , Camundongos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/genética , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Proteína p300 Associada a E1A/metabolismo , Proteína p300 Associada a E1A/genética , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Masculino , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Fatores de Transcrição de p300-CBP/metabolismo , Fatores de Transcrição de p300-CBP/genética , NF-kappa B/metabolismo
12.
BMC Cancer ; 24(1): 554, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698344

RESUMO

BACKGROUND: Prostate cancer is dependent on androgen receptor (AR) signaling, and androgen deprivation therapy (ADT) has proven effective in targeting prostate cancer. However, castration-resistant prostate cancer (CRPC) eventually emerges. AR signaling inhibitors (ARSI) have been also used, but resistance to these agents develops due to genetic AR alterations and epigenetic dysregulation. METHODS: In this study, we investigated the role of OCT1, a member of the OCT family, in an AR-positive CRPC patient-derived xenograft established from a patient with resistance to ARSI and chemotherapy. We conducted a genome-wide analysis chromatin immunoprecipitation followed by sequencing and bioinformatic analyses using public database. RESULTS: Genome-wide analysis of OCT1 target genes in PDX 201.1 A revealed distinct OCT1 binding sites compared to treatment-naïve cells. Bioinformatic analyses revealed that OCT1-regulated genes were associated with cell migration and immune system regulation. In particular, C-terminal Binding Protein 2 (CTBP2), an OCT1/AR target gene, was correlated with poor prognosis and immunosuppressive effects in the tumor microenvironment. Metascape revealed that CTBP2 knockdown affects genes related to the immune response to bacteria. Furthermore, TISIDB analysis suggested the relationship between CTBP2 expression and immune cell infiltration in prostate cancer, suggesting that it may contribute to immune evasion in CRPC. CONCLUSIONS: Our findings shed light on the genome-wide network of OCT1 and AR in AR-positive CRPC and highlight the potential role of CTBP2 in immune response and tumor progression. Targeting CTBP2 may represent a promising therapeutic approach for aggressive AR-positive CRPC. Further validation will be required to explore novel therapeutic strategies for CRPC management.


Assuntos
Oxirredutases do Álcool , Proteínas Correpressoras , Regulação Neoplásica da Expressão Gênica , Fator 1 de Transcrição de Octâmero , Neoplasias de Próstata Resistentes à Castração , Receptores Androgênicos , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Camundongos , Animais , Fator 1 de Transcrição de Octâmero/metabolismo , Fator 1 de Transcrição de Octâmero/genética , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Regulação para Cima , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Microambiente Tumoral , Transdução de Sinais
13.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791273

RESUMO

The HMG-domain containing transcription factor Sox10 plays a crucial role in regulating Schwann cell survival and differentiation and is expressed throughout the entire Schwann cell lineage. While its importance in peripheral myelination is well established, little is known about its role in the early stages of Schwann cell development. In a search for direct target genes of Sox10 in Schwann cell precursors, the transcriptional co-repressor Tle4 was identified. At least two regions upstream of the Tle4 gene appear involved in mediating the Sox10-dependent activation. Once induced, Tle4 works in tandem with the bHLH transcriptional repressor Hes1 and exerts a dual inhibitory effect on Sox10 by preventing the Sox10 protein from transcriptionally activating maturation genes and by suppressing Sox10 expression through known enhancers of the gene. This mechanism establishes a regulatory barrier that prevents premature activation of factors involved in differentiation and myelin formation by Sox10 in immature Schwann cells. The identification of Tle4 as a critical downstream target of Sox10 sheds light on the gene regulatory network in the early phases of Schwann cell development. It unravels an elaborate regulatory circuitry that fine-tunes the timing and extent of Schwann cell differentiation and myelin gene expression.


Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA , Fatores de Transcrição SOXE , Células de Schwann , Animais , Humanos , Camundongos , Ratos , Diferenciação Celular/genética , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Bainha de Mielina/metabolismo , Células de Schwann/metabolismo , Células de Schwann/citologia , Fatores de Transcrição SOXE/metabolismo , Fatores de Transcrição SOXE/genética , Fatores de Transcrição HES-1/metabolismo , Fatores de Transcrição HES-1/genética , Proteínas de Ligação a DNA/metabolismo
14.
Nucleic Acids Res ; 52(11): 6472-6489, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38752489

RESUMO

Orphan nuclear receptors (NRs), such as COUP-TF1, COUP-TF2, EAR2, TR2 and TR4, are implicated in telomerase-negative cancers that maintain their telomeres through the alternative lengthening of telomeres (ALT) mechanism. However, how telomere association of orphan NRs is involved in ALT activation remains unclear. Here, we demonstrate that telomeric tethering of orphan NRs in human fibroblasts initiates formation of ALT-associated PML bodies (APBs) and features of ALT activity, including ALT telomere DNA synthesis, telomere sister chromatid exchange, and telomeric C-circle generation, suggesting de novo ALT induction. Overexpression of orphan NRs exacerbates ALT phenotypes in ALT cells, while their depletion limits ALT. Orphan NRs initiate ALT via the zinc finger protein 827, suggesting the involvement of chromatin structure alterations for ALT activation. Furthermore, we found that orphan NRs and deficiency of the ALT suppressor ATRX-DAXX complex operate in concert to promote ALT activation. Moreover, PML depletion by gene knockout or arsenic trioxide treatment inhibited ALT induction in fibroblasts and ALT cancer cells, suggesting that APB formation underlies the orphan NR-induced ALT activation. Importantly, arsenic trioxide administration abolished APB formation and features of ALT activity in ALT cancer cell line-derived mouse xenografts, suggesting its potential for further therapeutic development to treat ALT cancers.


Assuntos
Fibroblastos , Proteína da Leucemia Promielocítica , Homeostase do Telômero , Humanos , Animais , Proteína da Leucemia Promielocítica/metabolismo , Proteína da Leucemia Promielocítica/genética , Camundongos , Fibroblastos/metabolismo , Telômero/metabolismo , Telômero/genética , Proteína Nuclear Ligada ao X/genética , Proteína Nuclear Ligada ao X/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Troca de Cromátide Irmã , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular Tumoral , Trióxido de Arsênio/farmacologia , Chaperonas Moleculares
15.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791218

RESUMO

KCTD1 plays crucial roles in regulating both the SHH and WNT/ß-catenin signaling pathways, which are essential for tooth development. The objective of this study was to investigate if genetic variants in KCTD1 might also be associated with isolated dental anomalies. We clinically and radiographically investigated 362 patients affected with isolated dental anomalies. Whole exome sequencing identified two unrelated families with rare (p.Arg241Gln) or novel (p.Pro243Ser) variants in KCTD1. The variants segregated with the dental anomalies in all nine patients from the two families. Clinical findings of the patients included taurodontism, unseparated roots, long roots, tooth agenesis, a supernumerary tooth, torus palatinus, and torus mandibularis. The role of Kctd1 in root development is supported by our immunohistochemical study showing high expression of Kctd1 in Hertwig epithelial root sheath. The KCTD1 variants in our patients are the first variants found to be located in the C-terminal domain, which might disrupt protein-protein interactions and/or SUMOylation and subsequently result in aberrant WNT-SHH-BMP signaling and isolated dental anomalies. Functional studies on the p.Arg241Gln variant are consistent with an impact on ß-catenin levels and canonical WNT signaling. This is the first report of the association of KCTD1 variants and isolated dental anomalies.


Assuntos
Proteínas Correpressoras , Variação Genética , Anormalidades Dentárias , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , beta Catenina/genética , beta Catenina/metabolismo , Proteínas Correpressoras/genética , Sequenciamento do Exoma , Linhagem , Anormalidades Dentárias/genética , Via de Sinalização Wnt/genética
16.
Sci Adv ; 10(20): eadk9076, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38748792

RESUMO

Acute myeloid leukemia (AML) driven by the activation of EVI1 due to chromosome 3q26/MECOM rearrangements is incurable. Because transcription factors such as EVI1 are notoriously hard to target, insight into the mechanism by which EVI1 drives myeloid transformation could provide alternative avenues for therapy. Applying protein folding predictions combined with proteomics technologies, we demonstrate that interaction of EVI1 with CTBP1 and CTBP2 via a single PLDLS motif is indispensable for leukemic transformation. A 4× PLDLS repeat construct outcompetes binding of EVI1 to CTBP1 and CTBP2 and inhibits proliferation of 3q26/MECOM rearranged AML in vitro and in xenotransplant models. This proof-of-concept study opens the possibility to target one of the most incurable forms of AML with specific EVI1-CTBP inhibitors. This has important implications for other tumor types with aberrant expression of EVI1 and for cancers transformed by different CTBP-dependent oncogenic transcription factors.


Assuntos
Oxirredutases do Álcool , Proteínas de Ligação a DNA , Leucemia Mieloide Aguda , Proteína do Locus do Complexo MDS1 e EVI1 , Animais , Humanos , Camundongos , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/genética , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteína do Locus do Complexo MDS1 e EVI1/metabolismo , Proteína do Locus do Complexo MDS1 e EVI1/genética , Ligação Proteica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
17.
Proc Natl Acad Sci U S A ; 121(23): e2318740121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805275

RESUMO

Repressor element-1 silencing transcription factor (REST) is required for the formation of mature neurons. REST dysregulation underlies a key mechanism of neurodegeneration associated with neurological disorders. However, the mechanisms leading to alterations of REST-mediated silencing of key neurogenesis genes are not known. Here, we show that BRCA1 Associated ATM Activator 1 (BRAT1), a gene linked to neurodegenerative diseases, is required for the activation of REST-responsive genes during neuronal differentiation. We find that INTS11 and INTS9 subunits of Integrator complex interact with BRAT1 as a distinct trimeric complex to activate critical neuronal genes during differentiation. BRAT1 depletion results in persistence of REST residence on critical neuronal genes disrupting the differentiation of NT2 cells into astrocytes and neuronal cells. We identified BRAT1 and INTS11 co-occupying the promoter region of these genes and pinpoint a role for BRAT1 in recruiting INTS11 to their promoters. Disease-causing mutations in BRAT1 diminish its association with INTS11/INTS9, linking the manifestation of disease phenotypes with a defect in transcriptional activation of key neuronal genes by BRAT1/INTS11/INTS9 complex. Finally, loss of Brat1 in mouse embryonic stem cells leads to a defect in neuronal differentiation assay. Importantly, while reconstitution with wild-type BRAT1 restores neuronal differentiation, the addition of a BRAT1 mutant is unable to associate with INTS11/INTS9 and fails to rescue the neuronal phenotype. Taken together, our study highlights the importance of BRAT1 association with INTS11 and INTS9 in the development of the nervous system.


Assuntos
Diferenciação Celular , Cromatina , Neurogênese , Neurônios , Proteínas Repressoras , Humanos , Cromatina/metabolismo , Cromatina/genética , Proteínas Correpressoras , Proteínas do Tecido Nervoso , Neurogênese/genética , Neurônios/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética
19.
Am J Respir Cell Mol Biol ; 71(1): 53-65, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38574238

RESUMO

Acute lung injury (ALI) is a common respiratory disease characterized by diffuse alveolar injury and interstitial edema, as well as a hyperinflammatory response, lung cell damage, and oxidative stress. Foxq1, a member of the FOX family of transcription factors, is expressed in various tissues, such as the lungs, liver, and kidneys, and contributes to various biological processes, such as stress, metabolism, cell cycle arrest, and aging-related apoptosis. However, the role of Foxq1 in ALI is unknown. We constructed ex vivo and in vivo ALI models by LPS tracheal perfusion of ICR mice and conditioned medium stimulation of injured MLE-12 cells. Foxq1 expression was increased, and its localization was altered, in our ALI model. In normal or injured MLE-12 cells, knockdown of Foxq1 promoted cell survival, and overexpression had the opposite effect. This regulatory effect was likely mediated by Tle1 and the NF-κB/Bcl2/Bax signaling pathway. These data suggest a potential link between Foxq1 and ALI, indicating that Foxq1 can be used as a biomarker for the diagnosis of ALI. Targeted inhibition of Foxq1 expression could promote alveolar epithelial cell survival and may provide a strategy for mitigating ALI.


Assuntos
Lesão Pulmonar Aguda , Células Epiteliais Alveolares , Fatores de Transcrição Forkhead , Camundongos Endogâmicos ICR , NF-kappa B , Transdução de Sinais , Animais , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , NF-kappa B/metabolismo , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/genética , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Camundongos , Masculino , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Apoptose , Linhagem Celular , Morte Celular , Humanos , Modelos Animais de Doenças
20.
Cardiovasc Res ; 120(8): 883-898, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38626254

RESUMO

AIMS: The activation of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in endothelial cells (ECs) contributes to vascular inflammation in atherosclerosis. Considering the high glycolytic rate of ECs, we delineated whether and how glycolysis determines endothelial NLRP3 inflammasome activation in atherosclerosis. METHODS AND RESULTS: Our results demonstrated a significant up-regulation of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), a key regulator of glycolysis, in human and mouse atherosclerotic endothelium, which positively correlated with NLRP3 levels. Atherosclerotic stimuli up-regulated endothelial PFKFB3 expression via sterol regulatory element-binding protein 2 (SREBP2) transactivation. EC-selective haplodeficiency of Pfkfb3 in Apoe-/- mice resulted in reduced endothelial NLRP3 inflammasome activation and attenuation of atherogenesis. Mechanistic investigations revealed that PFKFB3-driven glycolysis increased the NADH content and induced oligomerization of C-terminal binding protein 1 (CtBP1), an NADH-sensitive transcriptional co-repressor. The monomer form, but not the oligomer form, of CtBP1 was found to associate with the transcriptional repressor Forkhead box P1 (FOXP1) and acted as a transrepressor of inflammasome components, including NLRP3, caspase-1, and interleukin-1ß (IL-1ß). Interfering with NADH-induced CtBP1 oligomerization restored its binding to FOXP1 and inhibited the glycolysis-dependent up-regulation of NLRP3, Caspase-1, and IL-1ß. Additionally, EC-specific overexpression of NADH-insensitive CtBP1 alleviates atherosclerosis. CONCLUSION: Our findings highlight the existence of a glycolysis-dependent NADH/CtBP/FOXP1-transrepression pathway that regulates endothelial NLRP3 inflammasome activation in atherogenesis. This pathway represents a potential target for selective PFKFB3 inhibitors or strategies aimed at disrupting CtBP1 oligomerization to modulate atherosclerosis.


Assuntos
Aterosclerose , Modelos Animais de Doenças , Células Endoteliais , Glicólise , Inflamassomos , Camundongos Knockout para ApoE , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fosfofrutoquinase-2 , Animais , Fosfofrutoquinase-2/metabolismo , Fosfofrutoquinase-2/genética , Aterosclerose/metabolismo , Aterosclerose/genética , Aterosclerose/patologia , Humanos , Inflamassomos/metabolismo , Inflamassomos/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , NAD/metabolismo , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/genética , Camundongos Endogâmicos C57BL , Transdução de Sinais , Masculino , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Placa Aterosclerótica , Oxirredutases do Álcool , Proteína de Ligação a Elemento Regulador de Esterol 2
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