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1.
Gen Physiol Biophys ; 38(6): 485-495, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31829306

RESUMO

Circular RNA-microRNA (circRNA-miR) node has recently been found to modulate cancer process. Here, we investigated whether circCDYL and miR-150-5p exerted biological function in colon cancer cells. Colon cancer tissues were collected and subjected to qRT-PCR assay for circCDYL and miR-150-5p. SW480 and SW620 cells were forced to overexpress circCDYL and miR-150-5p before subjected to viability, colony formation, apoptosis, migration, invasion and protein (associated with proliferation, apoptosis and signaling pathways) assays. To confirm the combined function, the cells were transfected to simultaneously overexpress circCDYL and miR-150-5p. We found circCDYL was generally decreased while miR-150-5p was increased in colon cancer tissues in parallel with the para-carcinoma tissues. In circCDYL-transfected SW480 and SW620 cells, circCDYL decreased viability and promoted apoptosis with down-regulation of c-Myc and cyclin D1, up-regulation of p53, and cleavage of caspase-3 and PARP. Besides, migration and invasion behaviors were impeded. By contrast, miR-150-5p showed a carcinogenesis. However, suppressive role of circCDYL in cellular growth and migration was restrained in the cells simultaneously transfected with circCDYL and miR-150-5p, which was companied by down-regulation of PTEN and phosphorylation of PI3K, AKT, JAK2 and STAT5. circCDYL overexpression repressed cellular growth and migration via repressing miR-150-5p in colon cancer cells.


Assuntos
Proteínas Correpressoras/genética , Neoplasias do Colo , Hidroliases/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Humanos
2.
Eur J Med Chem ; 182: 111656, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31494467

RESUMO

Chemical probes of epigenetic 'readers' of histone post-translational modifications (PTMs) have become powerful tools for mechanistic and functional studies of their target proteins in physiology and pathology. However, only limited 'reader' probes have been developed, which restricted our understanding towards these macromolecules and their roles in cells or animals. Here, we reported a structure-guided approach to develop and characterize benzo [d]oxazol-2(3H)-one analogs as the first potent and selective small-molecule inhibitors of chromodomain Y-like (CDYL), a histone methyllysine reader protein. The binding conformation between the chromodomain of CDYL and the modified peptidomimetics was studied via molecular docking and dynamic simulations, facilitating subsequent virtual screening of tens of hits from Specs chemical library validated by SPR technique (KD values: from 271.1 µM to 5.4 µM). Further design and synthesis of 43 compounds helped to interpret the structure-activity relationship (SAR) that lead to the discovery of novel small-molecule inhibitors of CDYL. Compound D03 (KD: 0.5 µM) was discovered and showed excellent selectivity among other chromodomain proteins, including CDYL2 (>140 folds), CDY1 (no observed binding) and CBX7 (>32 folds). Moreover, we demonstrated that D03 engaged with endogenous CDYL in a dose-dependent manner, and perturbed the recruitment of CDYL onto chromatin, resulting in transcriptional derepression of its target genes. Finally, the results showed that D03 promoted the development and branching of neurodendrites by inhibiting CDYL in hippocampal and cortical cultured neurons. This study not only discovers the first selective small-molecule inhibitors of CDYL, but provids a new chemical tool to intervene the dynamic nature of bio-macromolecules involved in epigenetic mechanism.


Assuntos
Benzoxazóis/farmacologia , Proteínas Correpressoras/antagonistas & inibidores , Hidroliases/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Benzoxazóis/síntese química , Benzoxazóis/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Hidroliases/genética , Hidroliases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Neurônios/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
3.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370197

RESUMO

The interaction between androgen receptor (AR) and coactivator proteins plays a critical role in AR-mediated prostate cancer (PCa) cell growth, thus its inhibition is emerging as a promising strategy for PCa treatment. To develop potent inhibitors of the AR-coactivator interaction, we have designed and synthesized a series of bis-benzamides by modifying functional groups at the N/C-terminus and side chains. A structure-activity relationship study showed that the nitro group at the N-terminus of the bis-benzamide is essential for its biological activity while the C-terminus can have either a methyl ester or a primary carboxamide. Surveying the side chains with various alkyl groups led to the identification of a potent compound 14d that exhibited antiproliferative activity (IC50 value of 16 nM) on PCa cells. In addition, biochemical studies showed that 14d exerts its anticancer activity by inhibiting the AR-PELP1 interaction and AR transactivation.


Assuntos
Benzamidas/farmacologia , Proteínas Correpressoras/química , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/química , Fatores de Transcrição/química , Antagonistas de Androgênios/química , Antagonistas de Androgênios/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas Correpressoras/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Antígeno Prostático Específico/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Receptores Androgênicos/efeitos dos fármacos , Relação Estrutura-Atividade , Fatores de Transcrição/genética , Ativação Transcricional/efeitos dos fármacos
4.
EMBO J ; 38(19): e96659, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31454099

RESUMO

Loss of the histone H3.3-specific chaperone component ATRX or its partner DAXX frequently occurs in human cancers that employ alternative lengthening of telomeres (ALT) for chromosomal end protection, yet the underlying mechanism remains unclear. Here, we report that ATRX/DAXX does not serve as an immediate repressive switch for ALT. Instead, ATRX or DAXX depletion gradually induces telomere DNA replication dysfunction that activates not only homology-directed DNA repair responses but also cell cycle checkpoint control. Mechanistically, we demonstrate that this process is contingent on ATRX/DAXX histone chaperone function, independently of telomere length. Combined ATAC-seq and telomere chromatin immunoprecipitation studies reveal that ATRX loss provokes progressive telomere decondensation that culminates in the inception of persistent telomere replication dysfunction. We further show that endogenous telomerase activity cannot overcome telomere dysfunction induced by ATRX loss, leaving telomere repair-based ALT as the only viable mechanism for telomere maintenance during immortalization. Together, these findings implicate ALT activation as an adaptive response to ATRX/DAXX loss-induced telomere replication dysfunction.


Assuntos
Proteínas Correpressoras/genética , Chaperonas Moleculares/genética , Homeostase do Telômero , Telômero/metabolismo , Proteína Nuclear Ligada ao X/genética , Linhagem Celular , Reparo do DNA , Deleção de Genes , Células HEK293 , Humanos , Telomerase/metabolismo
5.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1864(12): 158514, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31465887

RESUMO

Adipogenesis has an important role in regulating energy balance, tissue homeostasis and disease pathogenesis. 3T3-L1 preadipocytes have been widely used as an in vitro model for studying adipocyte differentiation. We here show that KCTD1, a member of the potassium channel containing tetramerization domain proteins, plays an active role in adipogenesis. In particular, we show KCTD1 expression 3T3-L1 cells increases upon adipogenesis induction. Treatment of 3T3-L1 preadipocytes with Kctd1-specific siRNA inhibited the differentiation, as indicated by reduction of expression of the specific adipogenic markers C/ebpα, Pparγ2, Glut4, and Adiponectin. Moreover, we also show that the protein physically interacts with the transcription factor AP2α, a known inhibitor of adipogenesis, both in vitro and in cells. Interestingly, our data indicate that KCTD1 promotes adipogenesis through the interaction with AP2α and by removing it from the nucleus. Collectively, these findings disclose a novel role for KCTD1 and pave the way for novel strategies aimed at modulating adipogenesis.


Assuntos
Adipócitos/citologia , Adipogenia , Proteínas Correpressoras/metabolismo , Fator de Transcrição AP-2/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Proteínas Correpressoras/análise , Proteínas Correpressoras/genética , Regulação da Expressão Gênica , Camundongos , Mapas de Interação de Proteínas , Interferência de RNA , Fator de Transcrição AP-2/análise
6.
Nat Commun ; 10(1): 2915, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266946

RESUMO

The bile acid-sensing transcription factor farnesoid X receptor (FXR) regulates multiple metabolic processes. Modulation of FXR is desired to overcome several metabolic pathologies but pharmacological administration of full FXR agonists has been plagued by mechanism-based side effects. We have developed a modulator that partially activates FXR in vitro and in mice. Here we report the elucidation of the molecular mechanism that drives partial FXR activation by crystallography- and NMR-based structural biology. Natural and synthetic FXR agonists stabilize formation of an extended helix α11 and the α11-α12 loop upon binding. This strengthens a network of hydrogen bonds, repositions helix α12 and enables co-activator recruitment. Partial agonism in contrast is conferred by a kink in helix α11 that destabilizes the α11-α12 loop, a critical determinant for helix α12 orientation. Thereby, the synthetic partial agonist induces conformational states, capable of recruiting both co-repressors and co-activators leading to an equilibrium of co-activator and co-repressor binding.


Assuntos
Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/química , Animais , Linhagem Celular , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Humanos , Ligações de Hidrogênio , Ligantes , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Conformação Proteica em alfa-Hélice , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
7.
BMC Cancer ; 19(1): 740, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357957

RESUMO

BACKGROUND: Emerging evidence has shown that miR-1275 plays a critical role in tumour metastasis and the progression of various types of cancer. In this study, we analysed the role and mechanism of miR-1275 in the progression and prognosis of gastric cancer (GC). METHODS: Target genes of miR-1275 were identified and verified by luciferase assay and Western blotting. The function of miR-1275 in invasion and metastasis was analysed in vitro and in vivo in nude mice. The signal pathway regulated by miR-1275 was examined by qRT-PCR, Western blotting and chromatin immunoprecipitation analyses. The expression of miR-1275and JAZF1 were measured in specimens of GC and adjacent non cancerous tissues. RESULTS: We identified JAZF1 as a direct miR-1275 target. miR-1275 supresses migration and invasion of GC cells in vitro and in vivo, which was restored by JAZF1 overexpression. Moreover, JAZF1 was recognized as a direct regulator of Vimentin. Knocking-down miR-1275 or overexpressing JAZF1 resulted in upregulation of Vimentin but downregulation of E-cadherin. Meanwhile, we validated in 120 GC patients specimens that low miR-1275expression and high JAZF1 mRNA expression levels were closely associated with lymph node metastasis and poor prognosis. The expression of JAZF1 in protein level displayed the correlations with Vimentin but inversely with E-cadherin. CONCLUSIONS: Increased miR-1275 expression inhibited GC metastasis by regulating vimentin/E-cadherin via direct suppression of JAZF1expression, suggesting that miR-1275 is a tumour-suppressor miRNA with the potential as a prognostic biomarker or therapeutic target in GC.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Movimento Celular , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/metabolismo , MicroRNAs/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Vimentina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proteínas Correpressoras/genética , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfonodos/patologia , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias Gástricas/cirurgia , Transfecção
8.
BMC Res Notes ; 12(1): 343, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208445

RESUMO

OBJECTIVE: The NCoR-1 and NCoR-2 corepressors are products of an early gene duplication near the beginning of vertebrate evolution and play both overlapping and divergent roles in development and physiology. Alternative-splicing of NCoR-1 and NCoR-2 further customizes their functions. To better understand the evolutionary basis of this phenomenon we extended our prior study of NCoR-1 and NCoR-2 alternative-splicing to an expanded series of species. RESULTS: Alternative-splicing of NCoR-2 was observed in all vertebrates examined whereas alternative-splicing of NCoR-1 was largely limited to placental mammals. Notably the most prominent of the NCoR-1 alternative-splicing events specific to the placental lineage, in exon 37 that plays a key role in murine metabolism, mimics in many features an analogous alternative-splicing event that appeared in NCoR-2 much earlier at the beginning of the vertebrate radiation. Detection of additional alternative-splicing events, at exons 28 in NCoR-1 or NCoR-2, was limited to the Rodentia or Primates examined, indicating both corepressor paralogs continued to acquire additional splice variations more recently and independently of one another. Our results suggest that the NCoR-1/NCoR-2 paralogs have been subject to a mix of shared and distinct selective pressures, resulting in the pattern of divergent and convergent alternative-splicing observed in extant species.


Assuntos
Processamento Alternativo , Mamíferos/genética , Correpressor 1 de Receptor Nuclear/genética , Correpressor 2 de Receptor Nuclear/genética , RNA Mensageiro/genética , Animais , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Evolução Molecular , Éxons/genética , Feminino , Humanos , Mamíferos/classificação , Mamíferos/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 2 de Receptor Nuclear/metabolismo , Filogenia , Placenta , Gravidez , Especificidade da Espécie
9.
Genes Dev ; 33(13-14): 747-762, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31123067

RESUMO

Prolonged cold exposure stimulates the recruitment of beige adipocytes within white adipose tissue. Beige adipocytes depend on mitochondrial oxidative phosphorylation to drive thermogenesis. The transcriptional mechanisms that promote remodeling in adipose tissue during the cold are not well understood. Here we demonstrate that the transcriptional coregulator transducin-like enhancer of split 3 (TLE3) inhibits mitochondrial gene expression in beige adipocytes. Conditional deletion of TLE3 in adipocytes promotes mitochondrial oxidative metabolism and increases energy expenditure, thereby improving glucose control. Using chromatin immunoprecipitation and deep sequencing, we found that TLE3 occupies distal enhancers in proximity to nuclear-encoded mitochondrial genes and that many of these binding sites are also enriched for early B-cell factor (EBF) transcription factors. TLE3 interacts with EBF2 and blocks its ability to promote the thermogenic transcriptional program. Collectively, these studies demonstrate that TLE3 regulates thermogenic gene expression in beige adipocytes through inhibition of EBF2 transcriptional activity. Inhibition of TLE3 may provide a novel therapeutic approach for obesity and diabetes.


Assuntos
Adipócitos Bege/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Glucose/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Cultivadas , Dieta Hiperlipídica , Metabolismo Energético/genética , Deleção de Genes , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Resistência à Insulina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Mitocôndrias/metabolismo , Termogênese/genética
10.
Arterioscler Thromb Vasc Biol ; 39(6): 1212-1226, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31043075

RESUMO

Objective- IL (interleukin)-33 has been shown to play a role in endothelial dysfunction, but its role in atherosclerosis is controversial. Therefore, the purpose of this study is to examine its role in vascular wall remodeling following injury. Approach and Results- Thrombin induced IL-33 expression in a time-dependent manner in human aortic smooth muscle cells and inhibition of its activity by its neutralizing antibody suppressed thrombin induced human aortic smooth muscle cell migration but not DNA synthesis. In exploring the mechanisms, we found that Par1 (protease-activated receptor 1), Gαq/11 (Gα protein q/11), PLCß3 (phospholipase Cß3), NFATc1 (nuclear factor of activated T cells), E2F1 (E2F transcription factor 1), and LMCD1 (LIM and cysteine-rich domains protein 1) are involved in thrombin-induced IL-33 expression and migration. Furthermore, we identified an NFAT-binding site at -100 nt that mediates thrombin-induced IL-33 promoter activity. Interestingly, we observed that NFATc1, E2F1, and LMCD1 bind to NFAT site in response to thrombin and found that LMCD1, while alone has no significant effect, enhanced either NFATc1 or E2F1-dependent IL-33 promoter activity. In addition, we found that guidewire injury induces IL-33 expression in SMC and its neutralizing antibodies substantially reduce SMC migration and neointimal growth in vivo. Increased expression of IL-33 was also observed in human atherosclerotic lesions as compared to arteries without any lesions. Conclusions- The above findings reveal for the first time that thrombin-induced human aortic smooth muscle cell migration and injury-induced neointimal growth require IL-33 expression. In addition, thrombin-induced IL-33 expression requires LMCD1 enhanced combinatorial activation of NFATc1 and E2F1.


Assuntos
Proteínas Correpressoras/metabolismo , Fator de Transcrição E2F1/metabolismo , Interleucina-33/metabolismo , Proteínas com Domínio LIM/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Fatores de Transcrição NFATC/metabolismo , Neointima , Lesões do Sistema Vascular/metabolismo , Animais , Sítios de Ligação , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas Correpressoras/genética , Modelos Animais de Doenças , Fator de Transcrição E2F1/genética , Feminino , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/lesões , Artéria Femoral/metabolismo , Artéria Femoral/patologia , Células HEK293 , Humanos , Interleucina-33/genética , Proteínas com Domínio LIM/genética , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Fatores de Transcrição NFATC/genética , Regiões Promotoras Genéticas , Transdução de Sinais , Regulação para Cima , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/patologia
11.
J Cutan Pathol ; 46(8): 599-602, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30989672

RESUMO

Capicua transcriptional repressor (CIC)-rearranged sarcomas are part of the group of Ewing-like sarcomas or atypical Ewing sarcomas which, thanks to the progress in molecular diagnosis, are being defined by particular genetic abnormalities separating this group into distinct entities with their own particular histological and immunohistochemical features, as well as different survival outcomes. We report the case of a healthy 28-year-old female presenting with a tender lesion on her forearm which after ultrasound examination was clinically favored to represent an infected sebaceous cyst. Hematoxylin-eosin staining showed a lobulated neoplasm within the subcutis composed of poorly differentiated epithelioid to round cells with a small amount of amphophilic cytoplasm. Frequent mitotic figures and tumor necrosis were present. Immunohistochemical studies showed patchy focal CD99 membranous positivity, negative WT1 and TLE1 staining and diffuse nuclear positivity for ETV4 (performed at outside laboratory). FISH analysis showed significant CIC rearrangement enabling a final diagnosis of an undifferentiated small round cell sarcoma harboring the t(4;19)(q35;q13.1) and CIC-DUX4 fusion. This case shows the importance of awareness of this entity as, unlike Ewing sarcoma, these lesions present in the soft tissues rather than bone and may, as in this case, arise in the superficial soft tissues and be submitted to a dermatopathology practice.


Assuntos
Cisto Epidérmico , Antebraço , Rearranjo Gênico , Proteínas de Homeodomínio , Proteínas de Fusão Oncogênica , Proteínas Repressoras , Sarcoma de Células Pequenas , Neoplasias Cutâneas , Adulto , Cromossomos Humanos Par 19/genética , Cromossomos Humanos Par 19/metabolismo , Cromossomos Humanos Par 4/genética , Cromossomos Humanos Par 4/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Cisto Epidérmico/genética , Cisto Epidérmico/metabolismo , Cisto Epidérmico/patologia , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Hibridização in Situ Fluorescente , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Sarcoma de Células Pequenas/genética , Sarcoma de Células Pequenas/metabolismo , Sarcoma de Células Pequenas/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Translocação Genética , Proteínas WT1/genética , Proteínas WT1/metabolismo
12.
PLoS One ; 14(3): e0213553, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30889214

RESUMO

DNA-RNA hybrids arise in all cell types, and are removed by multiple enzymes, including the trimeric ribonuclease, RNase H2. Mutations in human RNase H2 result in Aicardi-Goutières syndrome (AGS), an inflammatory brain disorder notable for being a Mendelian mimic of congenital viral infection. Previous studies have shown that several AGS-associated mutations of the RNase H2B subunit do not affect trimer stability or catalytic activity and are clustered on the surface of the complex, leading us to speculate that these mutations might impair important interactions of RNase H2 with so far unidentified proteins. In this study, we show that AGS mutations in this cluster impair the interaction of RNase H2 with several members of the CoREST chromatin-silencing complex that include the histone deacetylase HDAC2 and the demethylase KDM1A, the transcriptional regulators RCOR1 and GTFII-I as well as ZMYM3, an MYM-type zinc finger protein. We also show that the interaction is mediated by the zinc finger protein ZMYM3, suggesting that ZMYM3 acts as a novel type of scaffold protein coordinating interactions between deacetylase, demethylase and RNase H type enzymes, raising the question of whether coordination between histone modifications and the degradation of RNA-DNA hybrids may be required to prevent inflammation in humans.


Assuntos
Doenças Autoimunes do Sistema Nervoso/metabolismo , Proteínas Correpressoras/metabolismo , Histonas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Malformações do Sistema Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Ribonuclease H/metabolismo , Animais , Doenças Autoimunes do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/patologia , Proteínas Correpressoras/genética , Células HEK293 , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Histonas/genética , Humanos , Camundongos , Células-Tronco Embrionárias Murinas , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Mutação , Proteínas do Tecido Nervoso/genética , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/patologia , Proteínas Nucleares/genética , Ribonuclease H/genética
13.
Nat Commun ; 10(1): 1270, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894540

RESUMO

Gfi1b is a transcriptional repressor expressed in hematopoietic stem cells (HSCs) and megakaryocytes (MKs). Gfi1b deficiency leads to expansion of both cell types and abrogates the ability of MKs to respond to integrin. Here we show that Gfi1b forms complexes with ß-catenin, its co-factors Pontin52, CHD8, TLE3 and CtBP1 and regulates Wnt/ß-catenin-dependent gene expression. In reporter assays, Gfi1b can activate TCF-dependent transcription and Wnt3a treatment enhances this activation. This requires interaction between Gfi1b and LSD1 and suggests that a tripartite ß-catenin/Gfi1b/LSD1 complex exists, which regulates Wnt/ß-catenin target genes. Consistently, numerous canonical Wnt/ß-catenin target genes, co-occupied by Gfi1b, ß-catenin and LSD1, have their expression deregulated in Gfi1b-deficient cells. When Gfi1b-deficient cells are treated with Wnt3a, their normal cellularity is restored and Gfi1b-deficient MKs regained their ability to spread on integrin substrates. This indicates that Gfi1b controls both the cellularity and functional integrity of HSCs and MKs by regulating Wnt/ß-catenin signaling pathway.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Megacariócitos/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Via de Sinalização Wnt , Proteína Wnt3A/genética , beta Catenina/genética , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Ontologia Genética , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células-Tronco Hematopoéticas/citologia , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Células K562 , Megacariócitos/citologia , Camundongos , Camundongos Knockout , Anotação de Sequência Molecular , Cultura Primária de Células , Proteínas Proto-Oncogênicas/deficiência , Proteínas Repressoras/deficiência , Tamoxifeno , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
14.
Cancer Lett ; 450: 22-31, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-30771436

RESUMO

Evasion of apoptosis is a major contributing factor to the development of chemo- and radiotherapy resistance. Therefore, activation of non-apoptotic programmed cell death (PCD) could be an effective alternative against apoptosis-resistant cancers. In this study, we demonstrated in vitro and in vivo that metformin can induce pyroptosis, a non-apoptotic PCD, in esophageal squamous cell carcinoma (ESCC), a commonly known chemo-refractory cancer, especially at its advanced stages. Proline-, glutamic acid- and leucine-rich protein-1 (PELP1) is a scaffolding oncogene and upregulated PELP1 in advanced stages of ESCC is highly associated with cancer progression and patient outcomes. Intriguingly, metformin treatment leads to gasdermin D (GSDMD)-mediated pyroptosis, which is abrogated by forced expression of PELP1. Mechanistically, metformin induces pyroptosis of ESCC by targeting miR-497/PELP1 axis. Our findings suggest that metformin and any other pyroptosis-inducing reagents could serve as alternative treatments for chemo- and radiotherapy refractory ESCC or other cancers sharing the same pyroptosis mechanisms.


Assuntos
Proteínas Correpressoras/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Metformina/farmacologia , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Proliferação de Células/efeitos dos fármacos , Proteínas Correpressoras/biossíntese , Proteínas Correpressoras/genética , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Piroptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Regulação para Cima/efeitos dos fármacos
15.
Biol Psychiatry ; 85(8): 635-649, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30665597

RESUMO

BACKGROUND: Major depressive disorder is a prevalent and life-threatening illness in modern society. The susceptibility to major depressive disorder is profoundly influenced by environmental factors, such as stressful lifestyle or traumatic events, which could impose maladaptive transcriptional program through epigenetic regulation. However, the underlying molecular mechanisms remain elusive. Here, we examined the role of histone crotonylation, a novel type of histone modification, and chromodomain Y-like protein (CDYL), a crotonyl-coenzyme A hydratase and histone methyllysine reader, in this process. METHODS: We used chronic social defeat stress and microdefeat stress to examine the depressive behaviors. In addition, we combined procedures that diagnose behavioral strategy in male mice with histone extraction, viral-mediated CDYL manipulations, RNA sequencing, chromatin immunoprecipitation, Western blot, and messenger RNA quantification. RESULTS: The results indicate that stress-susceptible rodents exhibit lower levels of histone crotonylation in the medial prefrontal cortex concurrent with selective upregulation of CDYL. Overexpression of CDYL in the prelimbic cortex, a subregion of the medial prefrontal cortex, increases microdefeat-induced social avoidance behaviors and anhedonia in mice. Conversely, knockdown of CDYL in the prelimbic cortex prevents chronic social defeat stress-induced depression-like behaviors. Mechanistically, we show that CDYL inhibits structural synaptic plasticity mainly by transcriptional repression of neuropeptide VGF nerve growth factor inducible, and this activity is dependent on its dual effect on histone crotonylation and H3K27 trimethylation on the VGF promoter. CONCLUSIONS: Our results demonstrate that CDYL-mediated histone crotonylation plays a critical role in regulating stress-induced depression, providing a potential therapeutic target for major depressive disorder.


Assuntos
Proteínas Correpressoras/metabolismo , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/psicologia , Histonas/metabolismo , Hidroliases/metabolismo , Estresse Psicológico/psicologia , Acil-CoA Desidrogenases/metabolismo , Acilação , Adenoviridae/genética , Animais , Proteínas Correpressoras/biossíntese , Proteínas Correpressoras/genética , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/prevenção & controle , Epigênese Genética , Técnicas de Silenciamento de Genes , Vetores Genéticos , Hidroliases/biossíntese , Hidroliases/genética , Masculino , Metilação , Camundongos , Fatores de Crescimento Neural/biossíntese , Plasticidade Neuronal , Córtex Pré-Frontal/metabolismo , Ratos , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo , Regulação para Cima
16.
Epigenetics Chromatin ; 12(1): 2, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30602385

RESUMO

BACKGROUND: Boundaries in the Drosophila bithorax complex delimit autonomous regulatory domains that activate the parasegment (PS)-specific expression of homeotic genes. The Fab-7 boundary separates the iab-6 and iab-7 regulatory domains that control Abd-B expression in PS11 and PS12. This boundary is composed of multiple functionally redundant elements and has two key activities: it blocks crosstalk between iab-6 and iab-7 and facilitates boundary bypass. RESULTS: Here, we have used a structure-function approach to elucidate the biochemical properties and the in vivo activities of a conserved BEN domain protein, Insensitive, that is associated with Fab-7. Our biochemical studies indicate that in addition to the C-terminal BEN DNA-binding domain, Insv has two domains that mediate multimerization: one is a coiled-coil domain in the N-terminus, and the other is next to the BEN domain. These multimerization domains enable Insv to bind simultaneously to two canonical 8-bp recognition motifs, as well as to a ~ 100-bp non-canonical recognition sequence. They also mediate the assembly of higher-order multimers in the presence of DNA. Transgenic proteins lacking the N-terminal coiled-coil domain are compromised for boundary function in vivo. We also show that Insv interacts directly with CP190, a protein previously implicated in the boundary functions of several DNA-binding proteins, including Su(Hw) and dCTCF. While CP190 interaction is required for Insv binding to a subset of sites on polytene chromosomes, it has only a minor role in the boundary activity of Insv in the context of Fab-7. CONCLUSIONS: The subdivision of eukaryotic chromosomes into discrete topological domains depends upon the pairing of boundary elements. In flies, pairing interactions are specific and typically orientation dependent. They occur in cis between neighboring heterologous boundaries, and in trans between homologous boundaries. One potential mechanism for ensuring pairing-interaction specificity is the use of sequence-specific DNA-binding proteins that can bind simultaneously with two or more recognition sequences. Our studies indicate that Insv can assemble into a multivalent DNA-binding complex and that the N-terminal Insv multimerization domain is critical for boundary function.


Assuntos
Proteínas Correpressoras/química , Proteínas de Drosophila/química , Multimerização Proteica , Animais , Sítios de Ligação , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Elementos Isolantes , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Ligação Proteica
17.
Nat Commun ; 10(1): 313, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30659184

RESUMO

Osteoarthritis (OA) has been recognized as the most common chronic age-related disease. Cartilage degeneration influences OA therapy. Here we report that hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP) is essential for OA development. Elevated HPIP levels are found in OA patients. Col2a1-CreERT2/HPIPf/f mice exhibit obvious skeletal abnormalities compared with their HPIPf/f littermates. HPIP deficiency in mice protects against developing OA. Moreover, intra-articular injection of adeno-associated virus carrying HPIP-specific short hairpin RNA in vivo attenuates OA histological signs. Notably, in vitro RNA-sequencing and chromatin immunoprecipitation sequencing profiles identify that HPIP modulates OA cartilage degeneration through transcriptional activation of Wnt target genes. Mechanistically, HPIP promotes the transcription of Wnt targets by interacting with lymphoid enhancer binding factor 1 (LEF1). Furthermore, HPIP potentiates the transcriptional activity of LEF1 and acetylates histone H3 lysine 56 in the promoters of Wnt targets, suggesting that HPIP is an attractive target in OA regulatory network.


Assuntos
Cartilagem Articular/patologia , Proteínas Correpressoras/genética , Osteoartrite/genética , Osteoartrite/patologia , Animais , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/metabolismo , Imunoprecipitação da Cromatina , Proteínas Correpressoras/metabolismo , Dependovirus , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Interferente Pequeno/genética , Saccharomyces cerevisiae , Análise de Sequência de RNA
18.
Eur J Med Genet ; 62(9): 103539, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30240710

RESUMO

A 5,6 Mb de novo 19q12-q13.12 interstitial deletion was diagnosed prenatally by array-comparative genomic hybridization in a 26 weeks male fetus presenting with intra-uterine growth retardation, left clubfoot, atypical genitalia and dysmorphic features. Autopsic examination following termination of pregnancy identified a severe disorder of sex development (DSD) including hypospadias, micropenis, bifid scrotum and right cryptorchidism associated with signs of ectodermal dysplasia: scalp hypopigmentation, thick and frizzy hair, absence of eyelashes, poorly developed nails and a thin skin with prominent superficial veins. Other findings were abnormal lung lobation and facial dysmorphism. This new case of DSD with a 19q12q13 deletion expands the phenotypic spectrum associated with this chromosomal rearrangment and suggests that WTIP is a strong candidate gene involved in male sex differentiation.


Assuntos
Transtornos Cromossômicos/genética , Cromossomos Humanos Par 19/genética , Transtornos do Desenvolvimento Sexual/genética , Displasia Ectodérmica/genética , Retardo do Crescimento Fetal/genética , Deleção de Genes , Adulto , Transtornos Cromossômicos/patologia , Proteínas Correpressoras/genética , Proteínas do Citoesqueleto/genética , Transtornos do Desenvolvimento Sexual/patologia , Displasia Ectodérmica/patologia , Feminino , Retardo do Crescimento Fetal/patologia , Humanos , Masculino , Gravidez
19.
Nat Rev Mol Cell Biol ; 20(2): 102-115, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30390028

RESUMO

Cell-type-specific gene expression is physiologically modulated by the binding of transcription factors to genomic enhancer sequences, to which chromatin modifiers such as histone deacetylases (HDACs) are recruited. Drugs that inhibit HDACs are in clinical use but lack specificity. HDAC3 is a stoichiometric component of nuclear receptor co-repressor complexes whose enzymatic activity depends on this interaction. HDAC3 is required for many aspects of mammalian development and physiology, for example, for controlling metabolism and circadian rhythms. In this Review, we discuss the mechanisms by which HDAC3 regulates cell type-specific enhancers, the structure of HDAC3 and its function as part of nuclear receptor co-repressors, its enzymatic activity and its post-translational modifications. We then discuss the plethora of tissue-specific physiological functions of HDAC3.


Assuntos
Histona Desacetilases/genética , Animais , Cromatina/genética , Proteínas Correpressoras/genética , Elementos Facilitadores Genéticos/genética , Humanos , Processamento de Proteína Pós-Traducional/genética
20.
Plant Physiol ; 179(2): 477-490, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30514725

RESUMO

ABI5-BINDING PROTEIN2 (AFP2) negatively regulates the abscisic acid signal by accelerating ABI5 degradation during seed germination in Arabidopsis (Arabidopsis thaliana). The abscisic acid signal is reported to delay flowering by up-regulating Flowering Locus C expression, but the role of AFP2 in regulating flowering time is unknown. Here, we found that flowering time was markedly delayed and CONSTANS (CO) expression was reduced in a transgenic Arabidopsis line overexpressing AFP2 under LD conditions. Conversely, the loss-of-function afp2 mutant showed slightly earlier flowering, with higher CO expression. These data suggest that AFP2 negatively regulates photoperiod-dependent flowering time by modulating the CO signal. We then found that AFP2 exhibited circadian expression rhythms that peaked during the night. Furthermore, the C-terminus of AFP2 interacted with CO, while its N-terminal ethylene response factor-associated amphiphilic repression motif interacted with the transcriptional corepressor TOPLESS-related protein2 (TPR2). Thus, AFP2 bridges CO and TPR2 to form the CO-AFP2-TPR2 complex. Biochemical and genetic analyses showed that AFP2 mediated CO degradation during the night. AFP2 also recruited histone deacetylase activity at Flowering Locus T chromatin through its interaction with TPR2. Taken together, our results reveal an elaborate mechanism by which AFP2 modulates flowering time through coordinating the activity and stability of CO.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Flores/fisiologia , Chaperonas Moleculares/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte/genética , Cromatina/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Chaperonas Moleculares/genética , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Fotoperíodo , Plantas Geneticamente Modificadas , Fatores de Transcrição/genética
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