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1.
Nat Commun ; 12(1): 734, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531470

RESUMO

Driver genes with a mutually exclusive mutation pattern across tumor genomes are thought to have overlapping roles in tumorigenesis. In contrast, we show here that mutually exclusive prostate cancer driver alterations involving the ERG transcription factor and the ubiquitin ligase adaptor SPOP are synthetic sick. At the molecular level, the incompatible cancer pathways are driven by opposing functions in SPOP. ERG upregulates wild type SPOP to dampen androgen receptor (AR) signaling and sustain ERG activity through degradation of the bromodomain histone reader ZMYND11. Conversely, SPOP-mutant tumors stabilize ZMYND11 to repress ERG-function and enable oncogenic androgen receptor signaling. This dichotomy regulates the response to therapeutic interventions in the AR pathway. While mutant SPOP renders tumor cells susceptible to androgen deprivation therapies, ERG promotes sensitivity to high-dose androgen therapy and pharmacological inhibition of wild type SPOP. More generally, these results define a distinct class of antagonistic cancer drivers and a blueprint toward their therapeutic exploitation.


Assuntos
Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Repressoras/metabolismo , Regulador Transcricional ERG/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Imuno-Histoquímica , Imunoprecipitação , Masculino , Camundongos , Camundongos Nus , Mutação/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Neoplasias da Próstata/genética , Ligação Proteica , Proteômica , Receptores Androgênicos/metabolismo , Proteínas Repressoras/genética , Transdução de Sinais/fisiologia , Regulador Transcricional ERG/genética , Complexos Ubiquitina-Proteína Ligase/genética
2.
Nat Commun ; 12(1): 1045, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594072

RESUMO

Recurring chromosomal translocation t(10;17)(p15;q21) present in a subset of human acute myeloid leukemia (AML) patients creates an aberrant fusion gene termed ZMYND11-MBTD1 (ZM); however, its function remains undetermined. Here, we show that ZM confers primary murine hematopoietic stem/progenitor cells indefinite self-renewal capability ex vivo and causes AML in vivo. Genomics profilings reveal that ZM directly binds to and maintains high expression of pro-leukemic genes including Hoxa, Meis1, Myb, Myc and Sox4. Mechanistically, ZM recruits the NuA4/Tip60 histone acetyltransferase complex to cis-regulatory elements, sustaining an active chromatin state enriched in histone acetylation and devoid of repressive histone marks. Systematic mutagenesis of ZM demonstrates essential requirements of Tip60 interaction and an H3K36me3-binding PWWP (Pro-Trp-Trp-Pro) domain for oncogenesis. Inhibitor of histone acetylation-'reading' bromodomain proteins, which act downstream of ZM, is efficacious in treating ZM-induced AML. Collectively, this study demonstrates AML-causing effects of ZM, examines its gene-regulatory roles, and reports an attractive mechanism-guided therapeutic strategy.


Assuntos
Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Correpressoras/química , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Leucemia Mieloide Aguda/patologia , Lisina Acetiltransferase 5/metabolismo , Acetilação , Animais , Carcinogênese , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica , Modelos Animais de Doenças , Elementos Facilitadores Genéticos/genética , Regulação Leucêmica da Expressão Gênica , Genoma Humano , Células HEK293 , Células-Tronco Hematopoéticas/metabolismo , Histonas/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Camundongos Endogâmicos BALB C , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas de Fusão Oncogênica/metabolismo , Ligação Proteica , Domínios Proteicos , Fatores de Transcrição/metabolismo
3.
Nat Commun ; 12(1): 1026, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589589

RESUMO

Proprioceptive neurons (PNs) are essential for the proper execution of all our movements by providing muscle sensory feedback to the central motor network. Here, using deep single cell RNAseq of adult PNs coupled with virus and genetic tracings, we molecularly identify three main types of PNs (Ia, Ib and II) and find that they segregate into eight distinct subgroups. Our data unveil a highly sophisticated organization of PNs into discrete sensory input channels with distinct spatial distribution, innervation patterns and molecular profiles. Altogether, these features contribute to finely regulate proprioception during complex motor behavior. Moreover, while Ib- and II-PN subtypes are specified around birth, Ia-PN subtypes diversify later in life along with increased motor activity. We also show Ia-PNs plasticity following exercise training, suggesting Ia-PNs are important players in adaptive proprioceptive function in adult mice.


Assuntos
Retroalimentação Sensorial/fisiologia , Gânglios Espinais/metabolismo , Neurônios Motores/metabolismo , Propriocepção/fisiologia , Células Receptoras Sensoriais/metabolismo , Animais , Calbindina 1/genética , Calbindina 1/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Gânglios Espinais/citologia , Expressão Gênica , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/classificação , Neurônios Motores/citologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Condicionamento Físico Animal , Células Receptoras Sensoriais/classificação , Células Receptoras Sensoriais/citologia , Análise de Célula Única , Medula Espinal/citologia , Medula Espinal/metabolismo
4.
Plant Mol Biol ; 105(4-5): 463-482, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33474657

RESUMO

KEY MESSAGE: SCL3 inhibits transcriptional activity of IDD-DELLA complex by acting as a co-repressor and repression activity is enhanced in the presence of GAF1 in a TOPLESS-independent manner. GRAS [GIBBERELLIN-INSENSITIVE (GAI), REPRESSOR OF ga1-3 (RGA) and SCARECROW (SCR)] proteins are a family of plant-specific transcriptional regulators that play diverse roles in development and signaling. GRAS family DELLA proteins act as growth repressors by inhibiting gibberellin (GA) signaling in response to developmental and environmental cues. DELLAs also act as co-activators of transcription factor GAI-ASSOCIATED FACTOR1 (GAF1)/INDETERMINATE DOMAIN2 (IDD2), the GAF1-DELLA complex activating transcription of GAF1 target genes. GAF1 also interacts with TOPLESS (TPL), a transcriptional co-repressor, in the absence of DELLA, the GAF1-TPL complex repressing transcription of the target genes. SCARECROW-LIKE3 (SCL3), another member of the GRAS family, is thought to inhibit transcriptional activity of the IDD-DELLA complex through competitive interaction with IDD. Here, we also revealed that SCL3 inhibits transcriptional activation by the GAF1-DELLA complex via repression activity rather than via competitive inhibition of the GAF1-DELLA interaction. Moreover, the repression activity of SCL3 was enhanced by GAF1 in a TPL-independent manner. While the GRAS domain of DELLA has transcriptional activation activity, that of SCL3 has repression activity. SCL3 also inhibited transcriptional activity of GAF1-RGA fusion proteins. Results from the co-immunoprecipitation assays and the yeast three-hybrid assay suggested the possibility that SCL3 forms a ternary complex with GAF1 and DELLA. These findings provide important information on DELLA-regulated GA signaling and new insight into the transcriptional repression mechanism.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas Correpressoras/genética , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Ribonuclease P/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas Correpressoras/metabolismo , Immunoblotting , Ligação Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease P/metabolismo , Transdução de Sinais/genética , Técnicas do Sistema de Duplo-Híbrido
5.
Nat Commun ; 12(1): 628, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504795

RESUMO

Consolidated memory can be preserved or updated depending on the environmental change. Although such conflicting regulation may happen during memory updating, the flexibility of memory updating may have already been determined in the initial memory consolidation process. Here, we explored the gating mechanism for activity-dependent transcription in memory consolidation, which is unexpectedly linked to the later memory updating in Drosophila. Through proteomic analysis, we discovered that the compositional change in the transcriptional repressor, which contains the histone deacetylase Rpd3 and CoRest, acts as the gating mechanism that opens and closes the time window for activity-dependent transcription. Opening the gate through the compositional change in Rpd3/CoRest is required for memory consolidation, but closing the gate through Rpd3/CoRest is significant to limit future memory updating. Our data indicate that the flexibility of memory updating is determined through the initial activity-dependent transcription, providing a mechanism involved in defining memory state.


Assuntos
Proteínas Correpressoras/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Histona Desacetilase 1/metabolismo , Memória/fisiologia , Transcrição Genética , Acetilação , Animais , Comportamento Animal , Encéfalo/fisiologia , Loci Gênicos , Corpos Pedunculados/inervação , Ligação Proteica , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Am J Hum Genet ; 107(4): 622-635, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946763

RESUMO

Quantifying the functional effects of complex disease risk variants can provide insights into mechanisms underlying disease biology. Genome-wide association studies have identified 39 regions associated with risk of epithelial ovarian cancer (EOC). The vast majority of these variants lie in the non-coding genome, where they likely function through interaction with gene regulatory elements. In this study we first estimated the heritability explained by known common low penetrance risk alleles for EOC. The narrow sense heritability (hg2) of EOC overall and high-grade serous ovarian cancer (HGSOCs) were estimated to be 5%-6%. Partitioned SNP heritability across broad functional categories indicated a significant contribution of regulatory elements to EOC heritability. We collated epigenomic profiling data for 77 cell and tissue types from Roadmap Epigenomics and ENCODE, and from H3K27Ac ChIP-seq data generated in 26 ovarian cancer and precursor-related cell and tissue types. We identified significant enrichment of risk single-nucleotide polymorphisms (SNPs) in active regulatory elements marked by H3K27Ac in HGSOCs. To further investigate how risk SNPs in active regulatory elements influence predisposition to ovarian cancer, we used motifbreakR to predict the disruption of transcription factor binding sites. We identified 469 candidate causal risk variants in H3K27Ac peaks that are predicted to significantly break transcription factor (TF) motifs. The most frequently broken motif was REST (p value = 0.0028), which has been reported as both a tumor suppressor and an oncogene. Overall, these systematic functional annotations with epigenomic data improve interpretation of EOC risk variants and shed light on likely cells of origin.


Assuntos
Carcinoma Epitelial do Ovário/genética , Proteínas Correpressoras/genética , Cistadenocarcinoma Seroso/genética , Elementos Facilitadores Genéticos , Histonas/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/genética , Alelos , Sítios de Ligação , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/patologia , Mapeamento Cromossômico , Proteínas Correpressoras/metabolismo , Cistadenocarcinoma Seroso/diagnóstico , Cistadenocarcinoma Seroso/patologia , Feminino , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Histonas/metabolismo , Humanos , Padrões de Herança , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Penetrância , Polimorfismo de Nucleotídeo Único , Risco
7.
Am J Physiol Renal Physiol ; 319(4): F654-F663, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32715759

RESUMO

Acute kidney injury (AKI) is a frequent complication of sepsis and an important cause of morbidity and mortality worldwide. A cornerstone of sepsis-associated AKI is dysregulated inflammation, leading to increased tissue oxidative stress and free radical formation, which leads to multiple forms of cell death. DJ-1 is a peroxiredoxin protein with multiple functions, including its ability to control cellular oxidative stress. Although DJ-1 is expressed prominently by renal tubules, its role in AKI has not been investigated. In the present study, we examined the effect of DJ-1 deficiency in a murine model of endotoxin-induced AKI. Endotoxemia induced greater kidney injury in DJ-1-deficient mice. Furthermore, DJ-1 deficiency increased renal oxidative stress associated with increased renal tubular apoptosis and with expression of death domain-associated protein (DAXX). Similar to the in vivo model, in vitro experiments using a medullary collecting duct cell line (mIMCD3) and cytotoxic serum showed that serum obtained from wild-type mice resulted in increased expression of s100A8/s100A9, DAXX, and apoptosis in DJ-1-deficient mIMCD3 cells. Our findings demonstrate a novel renal protective role for renal tubular DJ-1 during endotoxemia through control of oxidative stress, renal inflammation, and DAXX-dependent apoptosis.


Assuntos
Lesão Renal Aguda/prevenção & controle , Endotoxemia/complicações , Túbulos Renais/enzimologia , Lipopolissacarídeos , Nefrite/prevenção & controle , Proteína Desglicase DJ-1/metabolismo , Lesão Renal Aguda/enzimologia , Lesão Renal Aguda/etiologia , Lesão Renal Aguda/patologia , Animais , Apoptose , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Linhagem Celular , Proteínas Correpressoras/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Túbulos Renais/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Chaperonas Moleculares/metabolismo , Nefrite/enzimologia , Nefrite/etiologia , Nefrite/patologia , Estresse Nitrosativo , Estresse Oxidativo , Proteína Desglicase DJ-1/genética , Transdução de Sinais
8.
Mol Cell ; 78(5): 903-914.e4, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32396821

RESUMO

LSD1 (lysine specific demethylase; also known as KDM1A), the first histone demethylase discovered, regulates cell-fate determination and is overexpressed in multiple cancers. LSD1 demethylates histone H3 Lys4, an epigenetic mark for active genes, but requires the CoREST repressor to act on nucleosome substrates. To understand how an accessory subunit (CoREST) enables a chromatin enzyme (LSD1) to function on a nucleosome and not just histones, we have determined the crystal structure of the LSD1/CoREST complex bound to a 191-bp nucleosome. We find that the LSD1 catalytic domain binds extranucleosomal DNA and is unexpectedly positioned 100 Å away from the nucleosome core. CoREST makes critical contacts with both histone and DNA components of the nucleosome, explaining its essential function in demethylating nucleosome substrates. Our studies also show that the LSD1(K661A) frequently used as a catalytically inactive mutant in vivo (based on in vitro peptide studies) actually retains substantial H3K4 demethylase activity on nucleosome substrates.


Assuntos
Histona Desmetilases/metabolismo , Histona Desmetilases/ultraestrutura , Sequência de Aminoácidos , Domínio Catalítico , Cromatina/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Cristalografia por Raios X/métodos , DNA/genética , DNA/metabolismo , Histona Desmetilases/genética , Histonas/metabolismo , Humanos , Metilação , Modelos Moleculares , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo , Peptídeos/metabolismo , Ligação Proteica , Conformação Proteica
9.
Oncogene ; 39(21): 4212-4226, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32251364

RESUMO

Impaired neuronal differentiation is a feature of neuroblastoma tumorigenesis, and the differentiation grade of neuroblastoma tumors is associated with patient prognosis. Detailed understanding of the molecular mechanisms underlying neuroblastoma differentiation will facilitate the development of effective treatment strategies. Recent studies have shown that myelin transcription factor 1 (MYT1) promotes vertebrate neurogenesis by regulating gene expression. We performed quantitative analysis of neuroblastoma samples, which revealed that MYT1 was differentially expressed among neuroblastoma patients with different pathological diagnoses. Analysis of clinical data showed that MYT1 overexpression was associated with a significantly shorter 3-year overall survival rate and poor differentiation in neuroblastoma specimens. MYT1 knockdown inhibited proliferation and promoted the expression of multiple differentiation-associated proteins. Integrated omics data indicated that many genes involved in neuro-differentiation were regulated by MYT1. Interestingly, many of these genes are targets of the REST complex; therefore, we further identified the physical interaction of MYT1 with LSD1/CoREST. Depletion of LSD1 or inhibition of LSD1 by ORY-1001 decreased MYT1 expression, providing an alternative approach to target MYT1. Taken together, our results indicate that MYT1 significantly attenuates cell differentiation by interacting with the LSD1/CoREST complex. MYT1 is, therefore, a promising therapeutic target for enhancing the neurite-inducing effect of retinoic acid and for inhibiting the growth of neuroblastoma.


Assuntos
Diferenciação Celular , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histona Desmetilases/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuroblastoma/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas Correpressoras/genética , Proteínas de Ligação a DNA/genética , Feminino , Histona Desmetilases/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Complexos Multiproteicos/genética , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Neuroblastoma/genética , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Fatores de Transcrição/genética
10.
Sci Adv ; 6(11): eaay4697, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32201722

RESUMO

Previously, we reported that chromodomain Y-like (CDYL) acts as a crotonyl-coenzyme A hydratase and negatively regulates histone crotonylation (Kcr). However, the global CDYL-regulated crotonylome remains unclear. Here, we report a large-scale proteomics analysis for protein Kcr. We identify 14,311 Kcr sites across 3734 proteins in HeLa cells, providing by far the largest crotonylome dataset. We show that depletion of CDYL alters crotonylome landscape affecting diverse cellular pathways. Specifically, CDYL negatively regulated Kcr of RPA1, and mutation of the Kcr sites of RPA1 impaired its interaction with single-stranded DNA and/or with components of resection machinery, supporting a key role of RPA1 Kcr in homologous recombination DNA repair. Together, our study indicates that protein crotonylation has important implication in various pathophysiological processes.


Assuntos
Proteínas Correpressoras/metabolismo , Hidroliases/metabolismo , Processamento de Proteína Pós-Traducional , Reparo de DNA por Recombinação , Proteína de Replicação A/metabolismo , Sobrevivência Celular/genética , Proteínas Correpressoras/genética , Dano ao DNA , DNA de Cadeia Simples/genética , Técnicas de Silenciamento de Genes , Células HeLa , Histonas/metabolismo , Humanos , Hidroliases/genética , Proteoma
11.
J Pharmacol Sci ; 143(2): 74-82, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32192854

RESUMO

BACKGROUND: Circular RNAs (circRNAs) play an important role in the tumorigenesis of glioma. Our study indicated that low hsa_circ_0008225 expression was associated with poor overall survival in patients with glioma. However, the relevant mechanism of hsa_circ_0008225 in glioma tumorigenesis remains unclear. METHODS: Two datasets (GSE86202 and GSE92322) were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed circRNAs (DEcircRNAs) between glioma tissues and matched normal tissues were screened using R language. RESULTS: A total of 79 overlapping DEcircRNAs were identified by comparison of glioma and matched normal tissues. In addition, low hsa_circ_0008225 expression was associated with poor overall survival in patients with glioma. Overexpression of hsa_circ_0008225 markedly inhibited the proliferation, migration and invasion of SHG44 cells via inducing apoptosis. Mechanically, overexpression of hsa_circ_0008225 increased the expression of miR-890 targeted gene ZMYND11 via acting as a competitive 'sponge' of miR-890. CONCLUSION: Our results suggested that hsa_circ_0008225 functions as a tumor inhibitor in glioma by sponging miR-890 and then promoting the function of ZMYND11. Therefore, hsa_circ_0008225 could be a potential prognostic biomarker for the treatment of glioma.


Assuntos
Carcinogênese/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/genética , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Glioma/genética , Glioma/patologia , MicroRNAs , RNA Circular/fisiologia , Apoptose/genética , Movimento Celular/genética , Expressão Gênica , Glioma/mortalidade , Humanos , Invasividade Neoplásica/genética , RNA Circular/genética , Taxa de Sobrevida , Células Tumorais Cultivadas
12.
Arterioscler Thromb Vasc Biol ; 40(5): 1256-1274, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32160773

RESUMO

OBJECTIVE: In view of our previous observations on differential expression of LMCD1 (LIM and cysteine-rich domains 1) in human versus rodents, we asked the question whether LMCD1 plays a species-specific role in the development of vascular lesions. Approach and Results: A combination of genetic, molecular, cellular, and disease models were used to test species-specific role of LMCD1 in the pathogenesis of vascular lesions. Here, we report species-specific regulation of LMCD1 expression in mediating vascular smooth muscle cell proliferation and migration during vascular wall remodeling in humans versus mice. Thrombin induced LMCD1 expression in human aortic smooth muscle cells but not mouse aortic smooth muscle cells via activation of Par1 (protease-activated receptor 1)-Gαq/11 (Gα protein q/11)-PLCß3 (phospholipase Cß3)-NFATc1 (nuclear factor of activated T cells 1) signaling. Furthermore, although LMCD1 mediates thrombin-induced proliferation and migration of both human aortic smooth muscle cells and mouse aortic smooth muscle cells via influencing E2F1 (E2F transcription factor 1)-mediated CDC6 (cell division cycle 6) expression and NFATc1-mediated IL (interleukin)-33 expression, respectively, in humans, it acts as an activator, and in mice, it acts as a repressor of these transcriptional factors. Interestingly, LMCD1 repressor activity was nullified by N-myristoyltransferase 2-mediated myristoylation in mouse. Besides, we found increased expression of LMCD1 in human stenotic arteries as compared to nonstenotic arteries. On the other hand, LMCD1 expression was decreased in neointimal lesions of mouse injured arteries as compared to noninjured arteries. CONCLUSIONS: Together, these observations reveal that LMCD1 acts as an activator and repressor of E2F1 and NFATc1 in humans and mice, respectively, in the induction of CDC6 and IL-33 expression during development of vascular lesions. Based on these findings, LMCD could be a potential target for drug development against restenosis and atherosclerosis in humans.


Assuntos
Proteínas Correpressoras/metabolismo , Fator de Transcrição E2F1/metabolismo , Interleucina-33/metabolismo , Proteínas com Domínio LIM/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fatores de Transcrição NFATC/metabolismo , Remodelação Vascular , Lesões do Sistema Vascular/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Proteínas Correpressoras/genética , Modelos Animais de Doenças , Fator de Transcrição E2F1/genética , Feminino , Regulação da Expressão Gênica , Humanos , Interleucina-33/genética , Proteínas com Domínio LIM/genética , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Ácido Mirístico/metabolismo , Fatores de Transcrição NFATC/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Especificidade da Espécie , Trombina/farmacologia , Remodelação Vascular/efeitos dos fármacos , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/patologia
13.
J Clin Pathol ; 73(6): 314-317, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32161069

RESUMO

BCL-6 transcriptional corepressor (BCOR) gene is located at Xp11.4 and encodes a protein which is involved in transcriptional repression in association with BCL-6 and epigenetic silencing through polycomb repressive complex 1 (PRC1). BCOR mutations are being identified in an increasing number of tumours which are diverse in their anatomical location and clinical setting. Interestingly, these tumours share similar and overlapping histological features, namely small round blue cell morphology and a myxoid background with delicate capillary channels. Clear cell sarcoma of the kidney, primitive myxoid mesenchymal tumour of infancy and central nervous system high-grade neuroepithelial tumour with BCOR alteration all share similar internal tandem duplications in the polycomb-group really interesting new gene (RING) finger homolog ubiquitin-likefold discriminator domain of BCOR Translocations resulting in BCOR fusion with CCNB3, MAML3 and ZC3H7B have been identified in undifferentiated round cell sarcoma. Subsets of high-grade endometrial stromal sarcoma and ossifying fibromyxoid tumour which have a more aggressive clinical course have been shown to harbour ZC3H7B-BCOR fusions. BCOR immunohistochemistry is an established marker with diagnostic utility.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Translocação Genética , Biomarcadores Tumorais/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Epigênese Genética , Duplicação Gênica , Fusão Gênica , Inativação Gênica , Humanos , Imuno-Histoquímica , Neoplasias/diagnóstico , Neoplasias/patologia , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Proteínas Repressoras/metabolismo
15.
Horm Cancer ; 11(2): 87-96, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32037484

RESUMO

Proline-, glutamic acid-, leucine-rich protein 1 (PELP1) is a novel estrogen receptor (ER) coregulator, demonstrated distinctive characters from other ERα coregulators, and has been suggested to be involved in metastasis of several cancers. In ERα-positive breast cancer, PELP1 overexpression enhanced ruffles and filopodium-like structure stimulated by estradiol (E2) through extranuclear cell signaling transduction hereby increased cell motility. However, whether PELP1 is also involved in extracellular matrix remodeling of ERα-positive breast cancer cells is still unknown. In this study, we investigated the role of PELP1 in E2-induced MMP-9 expression and the underlined mechanism. The results demonstrated the following: E2-induced ERα-positive MCF-7 breast cancer cell MMP-9 mRNA and protein expression in a rapid response and concentration-dependent manner. Knocked down PELP1 significantly suppressed E2-induced MMP-9 expression. E2-bovine serum albumin (BSA), a large molecular membrane-impenetrable conjugate of E2, can also upregulate MMP-9 protein expression in MCF-7, and the action of E2-BSA can be abolished by PI3K inhibitor LY294002; treating MCF-7 simultaneously with PELP1-shRNA and LY294002 did not show synergetic inhibitory effect on E2-BSA-induced MMP-9 expression. Our results indicated that estrogen-induced MMP-9 expression in ER-positive breast cancer cells may be through PELP1-mediated PI3K/Akt signaling pathway.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas Correpressoras/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Metaloproteinase 9 da Matriz/biossíntese , Fatores de Transcrição/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cromonas/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Células MCF-7 , Metaloproteinase 9 da Matriz/genética , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais
16.
Endocrinology ; 161(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32065829

RESUMO

ß-Cell dysfunction in type 2 diabetes (T2D) is associated with loss of cellular identity and mis-expression of alternative islet hormones, including glucagon. The molecular basis for these cellular changes has been attributed to dysregulation of core ß-cell transcription factors, which regulate ß-cell identity through activating and repressive mechanisms. The TLE1 gene lies near a T2D susceptibility locus and, recently, the glucagon repressive actions of this transcriptional coregulator have been demonstrated in vitro. We investigated whether TLE1 expression is disrupted in human T2D, and whether this is associated with increased islet glucagon-expressing cells. Automated image analysis following immunofluorescence in donors with (n = 7) and without (n = 7) T2D revealed that T2D was associated with higher islet α/ß cell ratio (Control: 0.7 ± 0.1 vs T2D: 1.6 ± 0.4; P < .05) and an increased frequency of bihormonal (insulin+/glucagon+) cells (Control: 0.8 ± 0.2% vs T2D: 2.0 ± 0.4%, P < .05). In nondiabetic donors, the majority of TLE1-positive cells were mono-hormonal ß-cells (insulin+/glucagon-: 98.2 ± 0.5%; insulin+/glucagon+: 0.7 ± 0.2%; insulin-/glucagon+: 1.1 ± 0.4%; P < .001). TLE1 expression was reduced in T2D (Control: 36 ± 2.9% vs T2D: 24 ± 2.6%; P < .05). Reduced islet TLE1 expression was inversely correlated with α/ß cell ratio (r = -0.55; P < .05). TLE1 knockdown in EndoC-ßH1 cells was associated with a 2.5-fold increase in glucagon gene mRNA and mis-expression of glucagon in insulin-positive cells. These data support TLE1 as a putative regulator of human ß-cell identity, with dysregulated expression in T2D associated with increased glucagon expression potentially reflecting ß- to α-cell conversion.


Assuntos
Proteínas Correpressoras/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Glucagon/metabolismo , Glucagon/metabolismo , Adulto , Idoso , Diabetes Mellitus Tipo 2/patologia , Feminino , Células Secretoras de Glucagon/patologia , Humanos , Secreção de Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Pessoa de Meia-Idade
17.
Nat Commun ; 11(1): 956, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075969

RESUMO

Nuclear receptor (NR) transcription factors use a conserved activation function-2 (AF-2) helix 12 mechanism for agonist-induced coactivator interaction and NR transcriptional activation. In contrast, ligand-induced corepressor-dependent NR repression appears to occur through structurally diverse mechanisms. We report two crystal structures of peroxisome proliferator-activated receptor gamma (PPARγ) in an inverse agonist/corepressor-bound transcriptionally repressive conformation. Helix 12 is displaced from the solvent-exposed active conformation and occupies the orthosteric ligand-binding pocket enabled by a conformational change that doubles the pocket volume. Paramagnetic relaxation enhancement (PRE) NMR and chemical crosslinking mass spectrometry confirm the repressive helix 12 conformation. PRE NMR also defines the mechanism of action of the corepressor-selective inverse agonist T0070907, and reveals that apo-helix 12 exchanges between transcriptionally active and repressive conformations-supporting a fundamental hypothesis in the NR field that helix 12 exchanges between transcriptionally active and repressive conformations.


Assuntos
Benzamidas/metabolismo , Proteínas Correpressoras/metabolismo , PPAR gama/química , PPAR gama/metabolismo , Piridinas/metabolismo , Apoproteínas/química , Apoproteínas/metabolismo , Sítios de Ligação , Proteínas Correpressoras/química , Cristalografia por Raios X , Células HEK293 , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Mutação , Coativadores de Receptor Nuclear/química , Coativadores de Receptor Nuclear/metabolismo , PPAR gama/agonistas , PPAR gama/genética , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade , Transcrição Genética
18.
Nat Commun ; 11(1): 384, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959826

RESUMO

Emergence of an aggressive androgen receptor (AR)-independent neuroendocrine prostate cancer (NEPC) after androgen-deprivation therapy (ADT) is well-known. Nevertheless, the majority of advanced-stage prostate cancer patients, including those with SPINK1-positive subtype, are treated with AR-antagonists. Here, we show AR and its corepressor, REST, function as transcriptional-repressors of SPINK1, and AR-antagonists alleviate this repression leading to SPINK1 upregulation. Increased SOX2 expression during NE-transdifferentiation transactivates SPINK1, a critical-player for maintenance of NE-phenotype. SPINK1 elicits epithelial-mesenchymal-transition, stemness and cellular-plasticity. Conversely, pharmacological Casein Kinase-1 inhibition stabilizes REST, which in cooperation with AR causes SPINK1 transcriptional-repression and impedes SPINK1-mediated oncogenesis. Elevated levels of SPINK1 and NEPC markers are observed in the tumors of AR-antagonists treated mice, and in a subset of NEPC patients, implicating a plausible role of SPINK1 in treatment-related NEPC. Collectively, our findings provide an explanation for the paradoxical clinical-outcomes after ADT, possibly due to SPINK1 upregulation, and offers a strategy for adjuvant therapies.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Tumores Neuroendócrinos/genética , Neoplasias da Próstata/genética , Inibidor da Tripsina Pancreática de Kazal/metabolismo , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Caseína Quinase I/antagonistas & inibidores , Caseína Quinase I/metabolismo , Linhagem Celular Tumoral , Proteínas Correpressoras/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Transcrição Genética/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Mol Neurobiol ; 57(1): 393-407, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31364026

RESUMO

Ten to 20% of western countries population suffers from major depression disorder (MDD). Stressful life events represent the main environmental risk factor contributing to the onset of MDD and other stress-related neuropsychiatric disorders. In this regard, investigating brain physiology of stress response underlying the remarkable individual variability in terms of behavioral outcome may uncover stress-vulnerability pathways as a source of candidate targets for conceptually new antidepressant treatments. Serum response factor (SRF) has been addressed as a stress transducer via promoting inherent experience-induced Immediate Early Genes (IEGs) expression in neurons. However, in resting conditions, SRF also represents a transcriptional repressor able to assemble the core LSD1/CoREST/HDAC2 corepressor complex, including demethylase and deacetylase activities. We here show that dominant negative SRF splicing isoform lacking most part of the transactivation domain, namely SRFΔ5, owes its transcriptional repressive behavior to the ability of assembling LSD1/CoREST/HDAC2 corepressor complex meanwhile losing its affinity for transcription-permissive cofactor ELK1. SRFΔ5 is highly expressed in the brain and developmentally regulated. In the light of its activity as negative modulator of dendritic spine density, SRFΔ5 increase along with brain maturation suggests a role in synaptic pruning. Upon acute psychosocial stress, SRFΔ5 isoform transiently increases its levels. Remarkably, when stress is chronically repeated, a different picture occurs where SRF protein becomes stably upregulated in vulnerable mice but not in resilient animals. These data suggest a role for SRFΔ5 that is restricted to acute stress response, while positive modulation of SRF during chronic stress matches the criteria for stress-vulnerability hallmark.


Assuntos
Processamento Alternativo/genética , Proteínas Correpressoras/metabolismo , Histona Desmetilases/metabolismo , Plasticidade Neuronal , Fator de Resposta Sérica/genética , Estresse Fisiológico , Animais , Forma Celular , Espinhas Dendríticas/metabolismo , Células HeLa , Hipocampo/metabolismo , Histona Desacetilase 2/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Fator de Resposta Sérica/metabolismo , Estresse Psicológico/patologia
20.
Cardiovasc Res ; 116(3): 633-644, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31147690

RESUMO

AIMS: Regulated cell death is a main contributor of myocardial ischaemia-reperfusion (IR) injury during acute myocardial infarction. In this context, targeting apoptosis could be a potent therapeutical strategy. In a previous study, we showed that DAXX (death-associated protein) was essential for transducing the FAS-dependent apoptotic signal during IR injury. The present study aims at evaluating the cardioprotective effects of a synthetic peptide inhibiting FAS:DAXX interaction. METHODS AND RESULTS: An interfering peptide was engineered and then coupled to the Tat cell penetrating peptide (Tat-DAXXp). Its internalization and anti-apoptotic properties were demonstrated in primary cardiomyocytes. Importantly, an intravenous bolus injection of Tat-DAXXp (1 mg/kg) 5 min before reperfusion in a murine myocardial IR model decreased infarct size by 48% after 24 h of reperfusion. In addition, Tat-DAXXp was still efficient after a 30-min delayed administration, and was completely degraded and eliminated within 24 h thereby reducing risks of potential side effects. Importantly, Tat-DAXXp reduced mouse early post-infarction mortality by 67%. Mechanistically, cardioprotection was supported by both anti-apoptotic and pro-survival effects, and an improvement of myocardial functional recovery as evidenced in ex vivo experiments. CONCLUSIONS: Our study demonstrates that a single dose of Tat-DAXXp injected intravenously at the onset of reperfusion leads to a strong cardioprotection in vivo by inhibiting IR injury validating Tat-DAXXp as a promising candidate for therapeutic application.


Assuntos
Apoptose/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacologia , Proteínas Correpressoras/antagonistas & inibidores , Chaperonas Moleculares/antagonistas & inibidores , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Proteínas Correpressoras/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Chaperonas Moleculares/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Transdução de Sinais , Receptor fas/metabolismo
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