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1.
Genes (Basel) ; 10(10)2019 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614865

RESUMO

This study identified a transcription factor that might bind to the 5' regulatory region of the HTR1A and explored the potential effect on 5-HT1A receptor expression. Based on JASPAR predictions, the binding of the transcription factor was demonstrated using the electrophoretic mobility shift assay (EMSA). Vectors over-expressing the transcription factor were co-transfected into HEK-293 and SK-N-SH cells with the recombinant pGL3 vector, and relative fluorescence intensity was measured to determine regulatory activity. Additionally, the qRT-PCR and Western blot were also used to identify whether the transcription factor modulated the endogenous expression of 5-HT1A receptor. The results suggest that the transcription factor CCAA/T enhancer binding protein beta (CEBPB) likely binds to the -1219 to -1209 bp (ATG+1) region of the HTR1A. Two sequences located in the -722 to -372 bp and -119 to +99 bp were also identified. Although the effect of CEBPB on endogenous 5-HT1A receptor expression was not significant, it exhibited the strong inhibition on the relative fluorescence intensity and the mRNA level of HTR1A. CEBPB inhibited the human HTR1A expression by binding to the sequence -1219 - -1209 bp. This is useful and informative for ascertaining the regulation of 5-HT1A receptor and mental diseases.


Assuntos
Região 5'-Flanqueadora , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Receptor 5-HT1A de Serotonina/genética , Regulação da Expressão Gênica , Células HEK293 , Humanos , Receptor 5-HT1A de Serotonina/metabolismo , Sequências Reguladoras de Ácido Nucleico
2.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31471107

RESUMO

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Macrófagos/metabolismo , Fibrose Pulmonar/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Animais , Linhagem Celular , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Humanos , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Regulação para Cima/fisiologia
3.
BMC Complement Altern Med ; 19(1): 246, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488172

RESUMO

BACKGROUND: Yangkyuksanwha-tang (YST) is an herbal medicine based on Sasang constitutional medicine (SCM) and is widely used in Korean traditional medicine. The aim of the study was to evaluate the effect of YST on obesity in high-fat diet (HFD)-induced obese mice. METHODS: We induced obesity in C57bl/6 J mice using a HFD, and then orally administered 300 mg/kg YST for 6 weeks. We measured body weight, food efficiency, organ and fat weight, serum biochemical parameters, and obesity-related gene expression, and carried out histological analysis at the end of the experimental period. RESULTS: YST significantly reduced the absolute body weight and food efficiency ratio. The serum, aminotransferase, glucose, total cholesterol, triglyceride, and low-density lipoprotein-cholesterol levels were significantly lower in the YST-treated group than in the control group, whereas the high-density lipoprotein-cholesterol level in the YST-treated group was significantly higher. The YST-treated group also showed a significant reduction in regional fatty tissues and the absolute weight of various organs. We also observed a significantly reduced expression of AP2/FABP4, C/EBP-ß, leptin, and SREBP1c/ADD1 mRNA, and significantly increased expression of UCP-2 and adiponectin mRNA in adipose tissue in the YST-treated group. YST also decreased the lipid droplet size and lipid accumulation in the liver, as well as adipocyte size in epididymal adipose tissue. At the dose tested, YST was non-toxic to the liver and kidneys of the mice. CONCLUSION: The results imply that YST has anti-obesity effects in obesity-induced mice. Although the number of experimental animals was limited and the drug effects concern mice, rather than humans, which have different constitutions, the study has valuable implications with respect to the general effects of YST.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Obesidade/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Fármacos Antiobesidade/química , Peso Corporal/efeitos dos fármacos , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , HDL-Colesterol/metabolismo , Dieta Hiperlipídica/efeitos adversos , Humanos , Leptina/genética , Leptina/metabolismo , Masculino , Medicina Tradicional Coreana , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Extratos Vegetais/química , Plantas Medicinais/química , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
4.
Mol Cell Biochem ; 462(1-2): 51-59, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31428903

RESUMO

Interferon-stimulated gene 15 (ISG15) is a member of the family of ubiquitin-like proteins. Similar to ubiquitin, conjugation of ISG15 to cellular proteins requires cascade reactions catalyzed by at least 2 enzymes, UbE1L and UbcH8. Expression of ISG15 and its conjugates is up-regulated in many cancer cells, yet the underlying mechanism of up-regulation is still unclear. In this study, we showed that TNF-α, similar to the response by IFN-ß, could directly induce expression of ISG15 and its conjugation machinery, UbE1L and UbcH8, in human lung carcinoma, A549. The early response of their expression was effectively blocked by specific inhibitors of p38 MAPK (SB202190) and JNK (SP600125), but not by B18R, a soluble type-I IFN receptor. In addition, luciferase reporter assay together with serial deletions and site-directed mutagenesis identified a putative C/EBPß binding element in the ISG15 promoter, which is necessary to the response by TNF-α. Taken together, expression of ISG15 and ISG15 conjugation machinery in cancer cells is directly up-regulated by TNF-α via p38 MAPK and JNK pathways through the activation of C/EBPß binding element in the ISG15 promoter. This study provides a new insight toward understanding the molecular mechanism of ISG15 system and inflammatory response in cancer progression.


Assuntos
Citocinas/genética , Neoplasias Pulmonares/genética , Sistema de Sinalização das MAP Quinases , Fator de Necrose Tumoral alfa/farmacologia , Enzimas Ativadoras de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/genética , Ubiquitinas/genética , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Sequência de Bases , Sítios de Ligação , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Citocinas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Biológicos , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Enzimas Ativadoras de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinas/metabolismo
5.
Medicine (Baltimore) ; 98(33): e16807, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31415393

RESUMO

BACKGROUND: Sepsis is a serious clinical condition with a poor prognosis, despite improvements in diagnosis and treatment.Therefore, novel biomarkers are necessary that can help with estimating prognosis and improving clinical outcomes of patients with sepsis. METHODS: The gene expression profiles GSE54514 and GSE63042 were downloaded from the GEO database. DEGs were screened by t test after logarithmization of raw data; then, the common DEGs between the 2 gene expression profiles were identified by up-regulation and down-regulation intersection. The DEGs were analyzed using bioinformatics, and a protein-protein interaction (PPI) survival network was constructed using STRING. Survival curves were constructed to explore the relationship between core genes and the prognosis of sepsis patients based on GSE54514 data. RESULTS: A total of 688 common DEGs were identified between survivors and non-survivors of sepsis, and 96 genes were involved in survival networks. The crucial genes Signal transducer and activator of transcription 5A (STAT5A), CCAAT/enhancer-binding protein beta (CEBPB), Myc proto-oncogene protein (MYC), and REL-associated protein (RELA) were identified and showed increased expression in sepsis survivors. These crucial genes had a positive correlation with patients' survival time according to the survival analysis. CONCLUSIONS: Our findings indicate that the genes STAT5A, CEBPB, MYC, and RELA may be important in predicting the prognosis of sepsis patients.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fator de Transcrição STAT5/metabolismo , Sepse/genética , Sepse/mortalidade , Fator de Transcrição RelA/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biologia Computacional , Bases de Dados Genéticas , Regulação para Baixo , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Mapas de Interação de Proteínas , Fatores de Tempo , Transcriptoma , Regulação para Cima
6.
Mol Cells ; 42(7): 530-545, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31362469

RESUMO

Tumor cells can vary epigenetically during ionizing irradiation (IR) treatment. These epigenetic variegations can influence IR response and shape tumor aggressiveness. However, epigenetic disturbance of histones after IR, implicating in IR responsiveness, has been elusive. Here, we investigate whether altered histone modification after IR can influence radiation responsiveness. The oncogenic CXCL12 mRNA and protein were more highly expressed in residual cancer cells from a hepatoma heterotopic murine tumor microenvironment and coculture of human hepatoma Huh7 and normal IMR90 cells after radiation. H3K4 methylation was also enriched and H3K9 methylation was decreased at its promoter region. Accordingly, invasiveness and the subpopulation of aggressive CD133+/CD24- cells increased after IR. Histone demethylase inhibitor IOX1 attenuated CXCL12 expression and the malignant subpopulation, suggesting that responses to IR can be partially mediated via histone modifications. Taken together, radiation-induced histone alterations at the CXCL12 promoter in hepatoma cells are linked to CXCL12 upregulation and increased aggressiveness in the tumor microenvironment.


Assuntos
Carcinoma Hepatocelular/genética , Quimiocina CXCL12/genética , Histonas/metabolismo , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Microambiente Tumoral/genética , Regulação para Cima/genética , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quimiocina CXCL12/metabolismo , Epigênese Genética/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Compostos Heterocíclicos/farmacologia , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Processamento de Proteína Pós-Traducional/efeitos da radiação , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo , Proteínas Recombinantes/farmacologia , Transcrição Genética/efeitos da radiação , Microambiente Tumoral/efeitos da radiação , Raios X
7.
Cancer Biother Radiopharm ; 34(8): 537-546, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31314588

RESUMO

Introduction: Growth differentiation factor 15 (GDF15), a newly identified member of transforming growth factor (GDF) superfamily, is upregulated in ovarian (OV) cancer. Upregulated GDF15 positively correlates with poor prognosis of OV cancer. Thus, elucidation of the mechanism underlying GDF15 overexpression is important. Method and Results: PROMO and JASPAR prediction software were used to find transcription factors for GDF15 expression. Data from TCGA database were analyzed to find long noncoding RNAs (lncRNAs) that were also abnormally expressed in OV cancer and had associations with GDF15 expression. Transcription factor CEBPB was predicted as an important regulator of GDF15, confirmed by luciferase reporter assay. However, CEBPB expression was not significantly changed in OV cancer. Data from TCGA database showed that lncRNA GAS5 is downregulated in OV cancer and its expression is negatively correlated with GDF15 expression. RPISeq showed high affinity of GAS5 to CEBPB and this was confirmed by RNA-binding protein immunoprecipitation assay. GAS5 overexpression increased its binding to CEBPB and consequently downregulated GDF15. GAS5 overexpression and GDF15 knockdown decreased viability and increased apoptosis of OV cancer cells, but CEBPB overexpression had opposite effects. However, simultaneous GAS5 and CEBPB overexpression or CEBPB overexpression together with GDF15 knockdown had no effect on cell viability and apoptosis. Conclusion: GAS5 functions as decoy of CEBPB, blocking transcription-promoting effect of CEBPB on GDF15.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Fator 15 de Diferenciação de Crescimento/metabolismo , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Estudos de Casos e Controles , Feminino , Fator 15 de Diferenciação de Crescimento/genética , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Prognóstico , RNA Longo não Codificante/genética , Células Tumorais Cultivadas
8.
Life Sci Alliance ; 2(3)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31101736

RESUMO

Autophagy is a conserved system that adapts to nutrient starvation, after which proteins and organelles are degraded to recycle amino acids in response to starvation. Recently, the ER was added to the list of targets of autophagic degradation. Autophagic degradation pathways of bulk ER and the specific proteins sorted through the ER are considered key mechanisms in maintaining ER homeostasis. Four ER-resident proteins (FAM134B, CCPG1, SEC62, and RTN3) have been identified as ER-resident cargo receptors, which contain LC3-interacting regions. In this study, we identified an N-terminal-truncated isoform of FAM134B (FAM134B-2) that contributes to starvation-induced ER-related autophagy. Hepatic FAM134B-2 but not full-length FAM134B (FAM134B-1) is expressed in a fed state. Starvation drastically induces FAM134B-2 but no other ER-resident cargo receptors through transcriptional activation by C/EBPß. C/EBPß overexpression increases FAM134B-2 recruitment into autophagosomes and lysosomal degradation. FAM134B-2 regulates lysosomal degradation of ER-retained secretory proteins such as ApoCIII. This study demonstrates that the C/EBPß-FAM134B-2 axis regulates starvation-induced selective ER-phagy.


Assuntos
Autofagia , Retículo Endoplasmático/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/metabolismo , Proteínas de Membrana/genética , Inanição/metabolismo , Sequência de Aminoácidos , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Camundongos , Isoformas de Proteínas , Transcrição Genética
9.
Toxicol Lett ; 312: 11-21, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059759

RESUMO

Methamphetamine (METH) is a widely abused illicit psychoactive drug. Our previous study has shown that CCAAT-enhancer binding protein ß (C/EBPß) is an important regulator in METH-induced neuronal autophagy and apoptosis. However, the detailed molecular mechanisms underlying this process remain poorly understood. Previous studies have demonstrated that DNA damage-inducible transcript 4 (DDIT4), Trib3 (tribbles pseudo kinase 3), alpha-synuclein (α-syn) are involved in METH-induced dopaminergic neurotoxicity. We hypothesized that C/EBPß is involved in METH-induced DDIT4-mediated neuronal autophagy and Trib3-mediated neuronal apoptosis. We tested our hypothesis by examining the effects of silencing C/EBPß, DDIT4, Trib3 or α-syn with small interfering ribonucleic acid (siRNA) on METH-induced autophagy and apoptosis in the human neuroblastoma SH-SY5Y cells. We also measured the levels of phosphorylated tuberous sclerosis complex 2 (TSC2) protein and Parkin protein level in SH-SY5Y cells. Furthermore, we demonstrated the effect of silencing C/EBPß on METH-caused neurotoxicity in the striatum of rats by injecting LV-shC/EBPß lentivirus using a stereotaxic positioning system. The results showed that METH exposure increased C/EBPß, DDIT4 protein expression. Elevated DDIT4 expression raised up p-TSC2/TSC2 protein expression ratio, inhibited mTOR signaling pathway, activating cell autophagy. We also found that METH exposure increased the expression of Trib3, α-syn, decreased the Parkin protein expression. Lowering levels of Parkin raised up α-syn expression, which initiated mitochondrial apoptosis by down-regulating anti-apoptotic Bcl-2, followed by up-regulation of pro-apoptotic Bax, resulting in translocation of cytochrome c (cyto c), an apoptogenic factor, from the mitochondria to cytoplasm and activation of caspase-dependent pathways. These findings were supported by data showing METH-induced autophagy and apoptosis was significantly inhibited by silencing C/EBPß, DDIT4, Trib3 or α-syn, or by Parkin over-expression. Based on the present data, a novel of mechanism on METH-induced cell toxicity is proposed, METH exposure increased C/EBPß protein expression, triggered DDIT4/TSC2/mTOR signaling pathway, and evoked Trib3/Parkin/α-syn-related mitochondrial apoptotic signaling pathway. Collectively, these results suggest that C/EBPß plays an important role in METH-triggered autophagy and apoptosis and it may be a potential target for therapeutics in METH-caused neurotoxicity.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Estimulantes do Sistema Nervoso Central/toxicidade , Metanfetamina/toxicidade , Neurônios/efeitos dos fármacos , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Masculino , Neuroblastoma , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
10.
J Biol Chem ; 294(24): 9642-9654, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31061100

RESUMO

ß-Catenin signaling is triggered by WNT proteins and is an important pathway that negatively regulates adipogenesis. However, the mechanisms controlling the expression of WNT proteins during adipogenesis remain incompletely understood. Lysine demethylase 5A (KDM5A) is a histone demethylase that removes trimethyl (me3) marks from lysine 4 of histone 3 (H3K4) and serves as a general transcriptional corepressor. Here, using the murine 3T3-L1 preadipocyte differentiation model and an array of biochemical approaches, including ChIP, immunoprecipitation, RT-qPCR, and immunoblotting assays, we show that Kdm5a is a target gene of CCAAT/enhancer-binding protein ß (C/EBPß), an important early transcription factor required for adipogenesis. We found that C/EBPß binds to the Kdm5a gene promoter and transactivates its expression. We also found that siRNA-mediated KDM5A down-regulation inhibits 3T3-L1 preadipocyte differentiation. The KDM5A knockdown significantly up-regulates the negative regulator of adipogenesis Wnt6, having increased levels of the H3K4me3 mark on its promoter. We further observed that WNT6 knockdown significantly rescues adipogenesis inhibited by the KDM5A knockdown. Moreover, we noted that C/EBPß negatively regulates Wnt6 expression by binding to the Wnt6 gene promoter and repressing Wnt6 transcription. Further experiments indicated that KDM5A interacts with C/EBPß and that their interaction cooperatively inhibits Wnt6 transcription. Of note, C/EBPß knockdown impaired the recruitment of KDM5A to the Wnt6 promoter, which had higher H3K4me3 levels. Our results suggest a mechanism involving C/EBPß and KDM5A activities that down-regulates the Wnt/ß-catenin pathway during 3T3-L1 preadipocyte differentiation.


Assuntos
Adipócitos/citologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Ativação Transcricional , Proteína Wnt1/metabolismo , beta Catenina/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Regulação da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Camundongos , Regiões Promotoras Genéticas , Proteína 2 de Ligação ao Retinoblastoma/genética , Proteína Wnt1/genética , beta Catenina/genética
11.
Br Poult Sci ; 60(4): 347-356, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31064204

RESUMO

1. CCAAT/enhancer binding proteins (C/EBPs), as a family of transcription factors, consists of six functionally and structurally related proteins which share a conserved basic leucine zipper (bZIP) DNA-binding domain. The aim of this study was to clone the full-length coding sequences (CDS) of C/EBP-α and -ß genes, and determine the abundance of these two genes in various tissues of white king pigeon (C. livia). 2. The complete cDNA sequences of C/EBP-α and -ß genes were cloned from pigeons by using PCR combined with rapid amplification of cDNA ends (RACE). The sequences were bioinformatically analysed, and the tissue distribution determined by quantitative real-time RT-PCR (qRT-PCR). 3. The results showed that the full-length cDNA sequences of pigeon C/EBP-α and -ß genes were 2,807bp and 1,778bp, respectively. The open reading frames of C/EBP-α (978 bp) and -ß (987bp) encoded 325 amino acids and 328 amino acids, respectively. The pigeon C/EBP-α and C/EBP-ß proteins were predicted to have a conserved basic leucine zipper (bZIP) domain, which is a common structure feature of the C/EBP family. Multiple sequence alignments indicated that pigeon C/EBP-α and -ß shared more than 90% amino-acid identity with their corresponding homologues in other avian species. Phylogenetic analysis revealed that these two proteins were highly conserved across different species and evolutionary processes. QRT-PCR results indicated that the pigeon C/EBP-α and -ß mRNA transcripts were expressed in all investigated organs. The mRNA expression levels of pigeon C/EBP-α in descending order, were in spleen, heart, liver, lung, kidney and muscle. The pigeon C/EBP-ß gene had the most abundant expression in lung, followed by the kidney, with minimal expression detected in muscle. 4. This study investigated the full-length cDNA sequences, genetic characteristics and tissue distribution of pigeon C/EBP-α and -ß genes and found that they may have functions in various tissues of pigeon. This provides a foundation for further study for regulatory mechanisms of these two genes in birds.


Assuntos
Proteínas Aviárias/genética , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Columbidae/genética , Sequência de Aminoácidos , Animais , Proteínas Aviárias/química , Proteínas Aviárias/metabolismo , Sequência de Bases , Proteína alfa Estimuladora de Ligação a CCAAT/química , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/química , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Clonagem Molecular , Columbidae/metabolismo , Perfilação da Expressão Gênica/veterinária , Filogenia , Alinhamento de Sequência/veterinária
12.
Cancer Sci ; 110(6): 2050-2062, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30945396

RESUMO

The PPAR coactivator-1α (PGC1α) is an important transcriptional co-activator in control of fatty acid metabolism. Mitochondrial fatty acid oxidation (FAO) is the primary pathway for the degradation of fatty acids and promotes NADPH and ATP production. Our previous study demonstrated that upregulation of carnitine palmitoyl transferase 1 A (CPT1A), the key regulator of FAO, promotes radiation resistance of nasopharyngeal carcinoma (NPC). In this study, we found that high expression of PGC1α is associated with poor overall survival in NPC patients after radiation treatment. Targeting PGC1α could sensitize NPC cells to radiotherapy. Mechanically, PGC1α binds to CCAAT/enhancer binding protein ß (CEBPB), a member of the transcription factor family of CEBP, to promote CPT1A transcription, resulting in activation of FAO. Our results revealed that the PGC1α/CEBPB/CPT1A/FAO signaling axis promotes radiation resistance of NPC. These findings indicate that the expression of PGC1α could be a prognostic indicator of NPC, and targeting FAO in NPC with high expression of PGC1α might improve the therapeutic efficacy of radiotherapy.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/genética , Carnitina O-Palmitoiltransferase/genética , Ácidos Graxos/metabolismo , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Estimativa de Kaplan-Meier , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Oxirredução/efeitos da radiação , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos da radiação , Interferência de RNA
13.
Biochim Biophys Acta Gene Regul Mech ; 1862(5): 547-556, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30946989

RESUMO

Claudins are a group of cell tight junction proteins that play versatile roles in cancer biology. Recent studies have correlated down-regulation of Claudins with augmented breast cancer malignancy and poor prognosis. The mechanism underlying repression of Claudin transcription in breast cancer cells is not well understood. Here we report that expression levels of Brahma (BRM) were down-regulated in triple negative breast cancer cells (MDA-231) compared to the less malignant MCF-7 cells and in high-grade human breast cancer specimens compared to low-grade ones. TGF-ß treatment in MCF-7 cells repressed BRM transcription likely through targeting C/EBPß. BRM over-expression suppressed whereas BRM knockdown promoted TGF-ß induced migration and invasion of MCF-7 cells. BRM down-regulation was accompanied by the loss of a panel of Claudins in breast cancer cells. BRM directly bound to the promoter region of Claudin genes via interacting with Sp1 and activated transcription by modulating histone modifications. Together, our data have identified a novel epigenetic pathway that links Claudin transcription to breast cancer metastasis.


Assuntos
Neoplasias da Mama/genética , Claudina-1/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Claudina-1/biossíntese , Feminino , Código das Histonas , Humanos , Células MCF-7 , Invasividade Neoplásica , Metástase Neoplásica , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo
14.
Am J Physiol Endocrinol Metab ; 316(6): E1081-E1092, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964708

RESUMO

Musclin is a muscle-secreted cytokine that disrupts glucose uptake and glycogen synthesis in type 2 diabetes. The purpose of this study was to investigate the mechanisms responsible for the regulation of musclin gene expression in response to treatment with palmitate. RNA sequencing results showed that biological processes activated by palmitate are mainly enriched in endoplasmic reticulum (ER) stress. The protein kinase RNA-like ER kinase (PERK) signaling pathway is involved in the regulation of musclin expression induced by palmitate. Chromatin immunoprecipitation data showed that activating transcription factor 4 (ATF4)-downstream of PERK-bound to the promoter of the C/EBPß gene. Notably, C/EBPß also contains a binding site in the region -94~-52 of the musclin gene promoter. Knockdown or knockout of PERK and ATF4 using short hairpin RNA or CRISPR-Cas9 decreased the expression of C/EBPß and musclin induced by palmitate. Furthermore, knockdown and knockout of C/EBPß alleviated the high expression of musclin in response to treatment with palmitate. Moreover, CRISPR-Cas9 knockout of the region -94~-52 in which C/EBPß binds to the promoter of musclin abrogated the induction of high musclin expression caused by palmitate. Collectively, these findings suggest that treatment with palmitate activates the PERK/ATF4 signaling pathway, which in turn increases the expression of C/EBPß. C/EBPß binds directly to the promoter of the musclin gene and upregulates its expression.


Assuntos
Fator 4 Ativador da Transcrição/efeitos dos fármacos , Proteína beta Intensificadora de Ligação a CCAAT/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Proteínas Musculares/efeitos dos fármacos , Palmitatos/farmacologia , Fatores de Transcrição/efeitos dos fármacos , eIF-2 Quinase/efeitos dos fármacos , Fator 4 Ativador da Transcrição/metabolismo , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , eIF-2 Quinase/metabolismo
15.
Cell Commun Signal ; 17(1): 21, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832675

RESUMO

BACKGROUND: Platelet-activating factor (PAF) is a potent lipid mediator whose involvement in the onset and progression of atherosclerosis is mediated by, among others, the modulation of cytokine expression patterns. The presence of multiple potential protein-tyrosine phosphatase (PTP) 1B substrates in PAF receptor signaling pathways brought us to investigate its involvement in PAF-induced cytokine expression in monocyte-derived dendritic cells (Mo-DCs) and to study the pathways involved in this modulation. METHODS: We used in-vitro-matured human dendritic cells and the HEK-293 cell line in our studies. PTP1B inhibition was though siRNAs and a selective inhibitor. Cytokine expression was studied with RT-PCR, luciferase assays and ELISA. Phosphorylation status of kinases and transcription factors was studied with western blotting. RESULTS: Here, we report that PTP1B was involved in the modulation of cytokine expression in PAF-stimulated Mo-DCs. A study of the down-regulation of PAF-induced IL-8 expression, by PTP1B, showed modulation of PAF-induced transactivation of the IL-8 promoter which was dependent on the presence of the C/EBPß -binding site. Results also suggested that PTP1B decreased PAF-induced IL-8 production by a glycogen synthase kinase (GSK)-3-dependent pathway via activation of the Src family kinases (SFK). These kinases activated an unidentified pathway at early stimulation times and the PI3K/Akt signaling pathway in a later phase. This change in GSK-3 activity decreased the C/EBPß phosphorylation levels of the threonine 235, a residue whose phosphorylation is known to increase C/EBPß transactivation potential, and consequently modified IL-8 expression. CONCLUSION: The negative regulation of GSK-3 activity by PTP1B and the consequent decrease in phosphorylation of the C/EBPß transactivation domain could be an important negative feedback loop by which cells control their cytokine production after PAF stimulation.


Assuntos
Interleucina-8/metabolismo , Fator de Ativação de Plaquetas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Sítios de Ligação , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Células HEK293 , Humanos , Interleucina-8/genética , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Fosfotreonina/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Regiões Promotoras Genéticas/genética , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo
16.
Int J Mol Sci ; 20(5)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871024

RESUMO

To better understand the inflammation-associated mechanisms modulating and terminating tumor necrosis factor (TNF-)induced signal transduction and the development of TNF tolerance, we analyzed both the proteome and the phosphoproteome in TNF long term-incubated (i.e., 48 h) primary human monocytes using liquid chromatography-mass spectrometry. Our analyses revealed the presence of a defined set of proteins characterized by reproducible changes in expression and phosphorylation patterns in long term TNF-treated samples. In total, 148 proteins and 569 phosphopeptides were significantly regulated (103 proteins increased, 45 proteins decreased; 377 peptides with increased and 192 peptides with decreased phosphorylation). A variety of these proteins are associated with the non-canonical nuclear factor κB (NF-κB) pathway (nuclear factor κB (NFKB) 2, v-rel reticuloendotheliosis viral oncogene homolog (REL) B, indolamin-2,3-dioxygenase (IDO), kynureninase (KYNU)) or involved in the negative regulation of the canonical NF-κB system. Within the phosphopeptides, binding motifs for specific kinases were identified. Glycogen synthase kinase (GSK) 3 proved to be a promising candidate, since it targets NF-κB inhibiting factors, such as CCAAT/enhancer binding protein (C/EBP) ß. Our experiments demonstrate that both proteome and phosphoproteome analysis can be effectively applied to study protein/phosphorylation patterns of primary monocytes. These results provide new regulatory candidates and evidence for a complex network of specific but synergistically acting/cooperating mechanisms enabling the affected cells to resist sustained TNF exposure and resulting in the resolution of inflammation.


Assuntos
Monócitos/metabolismo , Proteoma/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Células HeLa , Humanos , Inflamação/metabolismo , NF-kappa B/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Células THP-1
17.
Biochim Biophys Acta Gene Regul Mech ; 1862(4): 486-492, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30825655

RESUMO

The bZIP homodimers CEBPB and CREB1 bind DNA containing methylated cytosines differently. CREB1 binds stronger to the C/EBP half-site GCAA when the cytosine is methylated. For CEBPB, methylation of the same cytosine does not affect DNA binding. The X-ray structure of CREB1 binding the half site GTCA identifies an alanine in the DNA binding region interacting with the methyl group of T, structurally analogous to the methyl group of methylated C. This alanine is replaced with a valine in CEBPB. To explore the contribution of this amino acid to binding with methylated cytosine of the GCAA half-site, we made the reciprocal mutants CEBPB(V285A) and CREB1(A297V) and used protein binding microarrays (PBM) to examine binding to four types of double-stranded DNA (dsDNA): 1) DNA with cytosine in both strands (DNA(C|C)), 2) DNA with 5-methylcytosine (M) in one strand and cytosine in the second strand (DNA(M|C)), 3) DNA with 5-hydroxymethylcytosine (H) in one strand and cytosine in the second strand (DNA(H|C)), and 4) DNA with both cytosines in all CG dinucleotides containing 5-methylcytosine (DNA(5mCG)). When binding to DNA(C|C), CEBPB (V285A) preferentially binds the CRE consensus motif (TGACGTCA), similar to CREB1. The reciprocal mutant, CREB1(A297V) binds DNA with some similarity to CEBPB, with strongest binding to the methylated PAR site 8-mer TTACGTAA. These data demonstrate that V285 residue inhibits CEBPB binding to methylated cytosine of the GCAA half-site.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Metilação de DNA , DNA/metabolismo , Sequência de Bases , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Citosina/metabolismo , DNA/química , Mutação , Motivos de Nucleotídeos , Polimorfismo de Nucleotídeo Único , Análise Serial de Proteínas , Ligação Proteica
18.
Cells ; 8(2)2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754676

RESUMO

The CCAAT/enhancer-binding protein ß (C/EBPß) is a transcription factor that regulates cellular proliferation, differentiation, apoptosis and tumorigenesis. Although the pro-oncogenic roles of C/EBPß have been implicated in various human cancers, how it contributes to tumorigenesis or tumor progression has not been determined. Immunohistochemistry with human non-small cell lung cancer (NSCLC) tissues revealed that higher levels of C/EBPß protein were expressed compared to normal lung tissues. Knockdown of C/EBPß by siRNA reduced the proliferative capacity of NSCLC cells by delaying the G2/M transition in the cell cycle. In C/EBPß-knockdown cells, a prolonged increase in phosphorylation of cyclin dependent kinase 1 at tyrosine 15 (Y15-pCDK1) was displayed with simultaneously increased Wee1 and decreased Cdc25B expression. Chromatin immunoprecipitation (ChIP) analysis showed that C/EBPß bound to distal promoter regions of WEE1 and repressed WEE1 transcription through its interaction with histone deacetylase 2. Treatment of C/EBPß-knockdown cells with a Wee1 inhibitor induced a decrease in Y15-pCDK1 and recovered cells from G2/M arrest. In the xenograft tumors, the depletion of C/EBPß significantly reduced tumor growth. Taken together, these results indicate that Wee1 is a novel transcription target of C/EBPß that is required for the G2/M phase of cell cycle progression, ultimately regulating proliferation of NSCLC cells.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas de Ciclo Celular/metabolismo , Divisão Celular , Fase G2 , Proteínas Nucleares/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Proteína Quinase CDC2/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Fase G2/efeitos dos fármacos , Fase G2/genética , Histona Desacetilase 2/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Pirazóis/farmacologia , Pirimidinonas/farmacologia , Transcrição Genética/efeitos dos fármacos
19.
Biochem Biophys Res Commun ; 511(2): 404-408, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30808546

RESUMO

Claudin-4 (CLDN4), a crucial member of tight junction proteins, is aberrantly expressed in breast cancer cells and contributes to cell migration and invasion. However, the mechanisms controlling CLDN4 expression in breast cancer are poorly understood. Here, we reported that CLDN4 expression correlated positively with p21-activated kinase 4 (PAK4) expression in human breast cancer tissues. Knockdown of PAK4 in MDA-MB-231 and ZR-75-30 cells suppressed CLDN4 expression and significantly inhibited cell migration and invasion. Conversely, restoration of CLDN4 expression in PAK4-knockdown cells reversed the inhibition of migration and invasion. We identified CCAAT/enhancer-binding protein ß (CEBPB) as a novel transcriptional regulator of CLDN4 and confirmed that CEBPB bound to the -1093 to -991 bp region of the CLDN4 promoter. Importantly, we found that PAK4 enhanced CEBPB phosphorylation on Thr-235. In summary, we showed that PAK4-mediated CEBPB activation upregulated CLDN4 expression to promote breast cancer cell migration and invasion. Our results might contribute to understanding the mechanisms of CLDN4 regulation and suggest PAK4-CEBPB-CLDN4 axis as a potential therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Claudina-4/metabolismo , Transdução de Sinais , Quinases Ativadas por p21/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Movimento Celular , Claudina-4/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Fosforilação , Quinases Ativadas por p21/genética
20.
Cancer Res ; 79(7): 1331-1342, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30705122

RESUMO

C/EBPß is a key mediator of cancer-induced skeletal muscle wasting. However, the signaling mechanisms that activate C/EBPß in the cancer milieu are poorly defined. Here, we report cancer-induced muscle wasting requires the transcriptional cofactor p300, which is critical for the activation of C/EBPß. Conditioned media from diverse types of tumor cells as well as recombinant HSP70 and HSP90 provoked rapid acetylation of C/EBPß in myotubes, particularly at its Lys39 residue. Overexpression of C/EBPß with mutated Lys39 impaired Lewis lung carcinoma (LLC)-induced activation of the C/EBPß-dependent catabolic response, which included upregulation of E3 ligases UBR2 and atrogin1/MAFbx, increased LC3-II, and loss of muscle proteins both in myotubes and mouse muscle. Silencing p300 in myotubes or overexpressing a dominant negative p300 mutant lacking acetyltransferase activity in mouse muscle attenuated LLC tumor-induced muscle catabolism. Administration of pharmacologic p300 inhibitor C646, but not PCAF/GCN5 inhibitor CPTH6, spared LLC tumor-bearing mice from muscle wasting. Furthermore, mice with muscle-specific p300 knockout were resistant to LLC tumor-induced muscle wasting. These data suggest that p300 is a key mediator of LLC tumor-induced muscle wasting whose acetyltransferase activity may be targeted for therapeutic benefit in this disease. SIGNIFICANCE: These findings demonstrate that tumor-induced muscle wasting in mice is abrogated by knockout, mutation of Lys39 or Asp1399, and pharmacologic inhibition of p300.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/7/1331/F1.large.jpg.


Assuntos
Caquexia/fisiopatologia , Carcinoma Pulmonar de Lewis/patologia , Fatores de Transcrição de p300-CBP/fisiologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/química , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Células HEK293 , Humanos , Lisina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Fatores de Transcrição de p300-CBP/genética
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