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1.
EMBO J ; 42(14): e112614, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37096681

RESUMO

Tumor-initiating cells are major drivers of chemoresistance and attractive targets for cancer therapy, however, their identity in human pancreatic ductal adenocarcinoma (PDAC) and the key molecules underlying their traits remain poorly understood. Here, we show that a cellular subpopulation with partial epithelial-mesenchymal transition (EMT)-like signature marked by high expression of receptor tyrosine kinase-like orphan receptor 1 (ROR1) is the origin of heterogeneous tumor cells in PDAC. We demonstrate that ROR1 depletion suppresses tumor growth, recurrence after chemotherapy, and metastasis. Mechanistically, ROR1 induces the expression of Aurora kinase B (AURKB) by activating E2F through c-Myc to enhance PDAC proliferation. Furthermore, epigenomic analyses reveal that ROR1 is transcriptionally dependent on YAP/BRD4 binding at the enhancer region, and targeting this pathway reduces ROR1 expression and prevents PDAC growth. Collectively, our findings reveal a critical role for ROR1high cells as tumor-initiating cells and the functional importance of ROR1 in PDAC progression, thereby highlighting its therapeutic targetability.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteínas Nucleares/metabolismo , Linhagem Celular Tumoral , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Transição Epitelial-Mesenquimal , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Pancreáticas
2.
EMBO J ; 42(14): e113349, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37306101

RESUMO

NRF2 is a transcription factor responsible for antioxidant stress responses that is usually regulated in a redox-dependent manner. p62 bodies formed by liquid-liquid phase separation contain Ser349-phosphorylated p62, which participates in the redox-independent activation of NRF2. However, the regulatory mechanism and physiological significance of p62 phosphorylation remain unclear. Here, we identify ULK1 as a kinase responsible for the phosphorylation of p62. ULK1 colocalizes with p62 bodies, directly interacting with p62. ULK1-dependent phosphorylation of p62 allows KEAP1 to be retained within p62 bodies, thus activating NRF2. p62S351E/+ mice are phosphomimetic knock-in mice in which Ser351, corresponding to human Ser349, is replaced by Glu. These mice, but not their phosphodefective p62S351A/S351A counterparts, exhibit NRF2 hyperactivation and growth retardation. This retardation is caused by malnutrition and dehydration due to obstruction of the esophagus and forestomach secondary to hyperkeratosis, a phenotype also observed in systemic Keap1-knockout mice. Our results expand our understanding of the physiological importance of the redox-independent NRF2 activation pathway and provide new insights into the role of phase separation in this process.


Assuntos
Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Humanos , Animais , Camundongos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fosforilação , Proteína Sequestossoma-1/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Autofagia/fisiologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
3.
J Biol Chem ; 299(6): 104810, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37172729

RESUMO

RNA sequencing (RNA-seq) is a powerful technique for understanding cellular state and dynamics. However, comprehensive transcriptomic characterization of multiple RNA-seq datasets is laborious without bioinformatics training and skills. To remove the barriers to sequence data analysis in the research community, we have developed "RNAseqChef" (RNA-seq data controller highlighting expression features), a web-based platform of systematic transcriptome analysis that can automatically detect, integrate, and visualize differentially expressed genes and their biological functions. To validate its versatile performance, we examined the pharmacological action of sulforaphane (SFN), a natural isothiocyanate, on various types of cells and mouse tissues using multiple datasets in vitro and in vivo. Notably, SFN treatment upregulated the ATF6-mediated unfolded protein response in the liver and the NRF2-mediated antioxidant response in the skeletal muscle of diet-induced obese mice. In contrast, the commonly downregulated pathways included collagen synthesis and circadian rhythms in the tissues tested. On the server of RNAseqChef, we simply evaluated and visualized all analyzing data and discovered the NRF2-independent action of SFN. Collectively, RNAseqChef provides an easy-to-use open resource that identifies context-dependent transcriptomic features and standardizes data assessment.


Assuntos
Perfilação da Expressão Gênica , Internet , Isotiocianatos , RNA-Seq , Software , Sulfóxidos , Animais , Camundongos , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Isotiocianatos/farmacologia , Sulfóxidos/farmacologia , RNA-Seq/métodos , RNA-Seq/normas , Especificidade de Órgãos/efeitos dos fármacos , Reprodutibilidade dos Testes , Camundongos Obesos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Antioxidantes/metabolismo , Visualização de Dados
4.
Nucleic Acids Res ; 50(17): 9765-9779, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36095121

RESUMO

Nucleus-mitochondria crosstalk is essential for cellular and organismal homeostasis. Although anterograde (nucleus-to-mitochondria) pathways have been well characterized, retrograde (mitochondria-to-nucleus) pathways remain to be clarified. Here, we found that mitochondrial dysfunction triggered a retrograde signaling via unique transcriptional and chromatin factors in hepatic cells. Our transcriptomic analysis revealed that the loss of mitochondrial transcription factor A led to mitochondrial dysfunction and dramatically induced expression of amphiregulin (AREG) and other secretory protein genes. AREG expression was also induced by various mitochondria stressors and was upregulated in murine liver injury models, suggesting that AREG expression is a hallmark of mitochondrial damage. Using epigenomic and informatic approaches, we identified that mitochondrial dysfunction-responsive enhancers of AREG gene were activated by c-JUN/YAP1/TEAD axis and were repressed by chromatin remodeler BRG1. Furthermore, while mitochondrial dysfunction-activated enhancers were enriched with JUN and TEAD binding motifs, the repressed enhancers possessed the binding motifs for hepatocyte nuclear factor 4α, suggesting that both stress responsible and cell type-specific enhancers were reprogrammed. Our study revealed that c-JUN and YAP1-mediated enhancer activation shapes the mitochondrial stress-responsive phenotype, which may shift from metabolism to stress adaptation including protein secretion under such stressed conditions.


Assuntos
Epigenômica , Mitocôndrias , Anfirregulina/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , Fatores Nucleares de Hepatócito/metabolismo , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo
5.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34074765

RESUMO

Testicular androgen is a master endocrine factor in the establishment of external genital sex differences. The degree of androgenic exposure during development is well known to determine the fate of external genitalia on a spectrum of female- to male-specific phenotypes. However, the mechanisms of androgenic regulation underlying sex differentiation are poorly defined. Here, we show that the genomic environment for the expression of male-biased genes is conserved to acquire androgen responsiveness in both sexes. Histone H3 at lysine 27 acetylation (H3K27ac) and H3K4 monomethylation (H3K4me1) are enriched at the enhancer of male-biased genes in an androgen-independent manner. Specificity protein 1 (Sp1), acting as a collaborative transcription factor of androgen receptor, regulates H3K27ac enrichment to establish conserved transcriptional competency for male-biased genes in both sexes. Genetic manipulation of MafB, a key regulator of male-specific differentiation, and Sp1 regulatory MafB enhancer elements disrupts male-type urethral differentiation. Altogether, these findings demonstrate conservation of androgen responsiveness in both sexes, providing insights into the regulatory mechanisms underlying sexual fate during external genitalia development.


Assuntos
Genitália Masculina/metabolismo , Diferenciação Sexual , Acetilação , Androgênios , Animais , Sistemas CRISPR-Cas , Feminino , Regulação da Expressão Gênica , Histonas/metabolismo , Fator de Transcrição MafB , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Receptores Androgênicos , Fatores de Transcrição/metabolismo
6.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473789

RESUMO

In the adult mammalian brain, neurons are produced from neural stem cells (NSCs) residing in two niches-the subventricular zone (SVZ), which forms the lining of the lateral ventricles, and the subgranular zone in the hippocampus. Epigenetic mechanisms contribute to maintaining distinct cell fates by suppressing gene expression that is required for deciding alternate cell fates. Several histone deacetylase (HDAC) inhibitors can affect adult neurogenesis in vivo. However, data regarding the role of specific HDACs in cell fate decisions remain limited. Herein, we demonstrate that HDAC8 participates in the regulation of the proliferation and differentiation of NSCs/neural progenitor cells (NPCs) in the adult mouse SVZ. Specific knockout of Hdac8 in NSCs/NPCs inhibited proliferation and neural differentiation. Treatment with the selective HDAC8 inhibitor PCI-34051 reduced the neurosphere size in cultures from the SVZ of adult mice. Further transcriptional datasets revealed that HDAC8 inhibition in adult SVZ cells disturbs biological processes, transcription factor networks, and key regulatory pathways. HDAC8 inhibition in adult SVZ neurospheres upregulated the cytokine-mediated signaling and downregulated the cell cycle pathway. In conclusion, HDAC8 participates in the regulation of in vivo proliferation and differentiation of NSCs/NPCs in the adult SVZ, which provides insights into the underlying molecular mechanisms.


Assuntos
Células-Tronco Adultas , Células-Tronco Neurais , Intervenção Coronária Percutânea , Animais , Camundongos , Ventrículos Laterais , Inibidores de Histona Desacetilases , Proliferação de Células , Mamíferos
7.
Cancer Sci ; 114(4): 1541-1555, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36562400

RESUMO

The high glycolytic activity of cancer cells leads to lactic acidosis (LA) in the tumor microenvironment. LA is not merely a consequence of metabolic activities but also has functional roles in metabolic reprogramming and cancer progression. Cholangiocarcinoma (CCA) cells exhibit a high dependency on glycolysis for survival and growth, but the specific effects of LA on cellular characteristics remain unknown. Here, we demonstrate that long-term LA (LLA) reprograms the metabolic phenotype of CCA cells from glycolytic to oxidative and enhances their migratory activity. In CCA cell culture, short-term LA (24 h) showed a growth inhibitory effect, while extended LA exposure for more than 2 weeks (LLA) led to enhanced cell motility. Coincidentally, LLA enhanced the respiratory capacity with an increase in mitochondrial mass. Inhibition of mitochondrial function abolished LLA-induced cell motility, suggesting that metabolic remodeling affects the phenotypic outcomes. RNA-sequencing analysis revealed that LLA upregulated genes associated with cell migration and epithelial-mesenchymal transition (EMT), including thrombospondin-1 (THBS1), which encodes a pro-EMT-secreted protein. Inhibition of THBS1 resulted in the suppression of both LLA-induced cell motility and respiratory capacity. Moreover, high THBS1 expression was associated with poor survival in patients with CCA. Collectively, our study suggests that the increased expression of THBS1 by LLA promotes phenotypic alterations, leading to CCA progression.


Assuntos
Acidose Láctica , Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Regulação para Cima , Acidose Láctica/genética , Linhagem Celular Tumoral , Colangiocarcinoma/patologia , Transição Epitelial-Mesenquimal/genética , Fenótipo , Movimento Celular/genética , Ductos Biliares Intra-Hepáticos/metabolismo , Neoplasias dos Ductos Biliares/patologia , Trombospondinas/genética , Microambiente Tumoral/genética
8.
Mol Cell ; 60(4): 584-96, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26590716

RESUMO

Bivalent H3K4me3 and H3K27me3 chromatin domains in embryonic stem cells keep active developmental regulatory genes expressed at very low levels and poised for activation. Here, we show an alternative and previously unknown bivalent modified histone signature in lineage-committed mesenchymal stem cells and preadipocytes that pairs H3K4me3 with H3K9me3 to maintain adipogenic master regulatory genes (Cebpa and Pparg) expressed at low levels yet poised for activation when differentiation is required. We show lineage-specific gene-body DNA methylation recruits H3K9 methyltransferase SETDB1, which methylates H3K9 immediately downstream of transcription start sites marked with H3K4me3 to establish the bivalent domain. At the Cebpa locus, this prevents transcription factor C/EBPß binding, histone acetylation, and further H3K4me3 deposition and is associated with pausing of RNA polymerase II, which limits Cebpa gene expression and adipogenesis.


Assuntos
Adipócitos/citologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Metilação de DNA , Histonas/genética , PPAR gama/metabolismo , Células 3T3 , Adipócitos/fisiologia , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Cromatina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Estrutura Terciária de Proteína
9.
Cancer Sci ; 112(1): 254-264, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33141432

RESUMO

Diabetes is a major risk factor in the development and progression of several cancers including cholangiocarcinoma (CCA). However, the molecular mechanism by which hyperglycemia potentiates progression of CCA is not clearly understood. Here, we showed that a high glucose condition significantly increased reactive oxygen species (ROS) production and promoted aggressive phenotypes of CCA cells, including proliferation and migration activities. Mannosidase alpha class 2a member 2 (MAN2A2), was upregulated at both mRNA and protein levels in a high glucose- and ROS-dependent manner. In addition, cell proliferation and migration were significantly reduced by MAN2A2 knockdown. Based on our proteome and in silico analyses, we further found that chromodomain helicase DNA-binding protein 8 (CHD8) was induced by ROS signaling and regulated MAN2A2 expression. Overexpression of CHD8 increased MAN2A2 expression, while CHD8 knockdown dramatically reduced proliferation and migration as well as MAN2A2 expression in CCA cells. Moreover, both MAN2A2 and CHD8 were highly expressed with positive correlation in CCA tumor tissues. Collectively, these data suggested that high glucose conditions promote CCA progression through ROS-mediated upregulation of MAN2A2 and CHD8. Thus, glucose metabolism is a promising therapeutic target to control tumor progression in patients with CCA and diabetes.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glucose/metabolismo , Manosidases/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Colangiocarcinoma/patologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Hiperglicemia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
10.
Br J Cancer ; 123(4): 580-590, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32499570

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) has increased morbidity, and its high metastatic potential affects patient survival. Bromodomain containing 4 (BRD4) is a chromatin protein that associates with acetylated histone lysines and facilitates transcription. BRD4 has been implicated in cell proliferation, metastasis, and prognosis in several types of cancer. However, the role of BRD4 in OSCC remains to be elucidated. METHODS: We investigated the role of BRD4 and its potential utility as a therapeutic target in OSCC. RESULTS: JQ1, the BRD4 inhibitor, suppressed the cell proliferation, migration, and invasion in the OSCC cell lines and in vivo. JQ1 reduced the expression levels of 15 metastasis genes in OSCC, including matrix metallopeptidase 2 (MMP2). Our chromatin immunoprecipitation assay showed that JQ1 reduced the BRD4 binding to the histone H3 lysine 27 acetylation-enriched sites in the MMP2 locus. Analyses of biopsy specimens from OSCC patients revealed that the BRD4 and MMP2 expression levels were correlated in the cancerous regions, and both were highly expressed in lymph node metastasis cases, including delayed metastasis. CONCLUSIONS: BRD4 contributes to metastasis in OSCC, through the epigenetic regulation of the MMP2 gene, and thus BRD4 may represent a therapeutic target and a novel prediction indicator for metastasis.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Metástase Linfática/genética , Metaloproteinase 2 da Matriz/genética , Neoplasias Bucais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Azepinas/farmacologia , Carcinoma de Células Escamosas/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Masculino , Camundongos , Neoplasias Bucais/metabolismo , Prognóstico , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologia
11.
J Cell Sci ; 131(6)2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29487178

RESUMO

Although condensins play essential roles in mitotic chromosome assembly, Ki-67 (also known as MKI67), a protein localizing to the periphery of mitotic chromosomes, had also been shown to make a contribution to the process. To examine their respective roles, we generated a set of HCT116-based cell lines expressing Ki-67 and/or condensin subunits that were fused with an auxin-inducible degron for their conditional degradation. Both the localization and the dynamic behavior of Ki-67 on mitotic chromosomes were not largely affected upon depletion of condensin subunits, and vice versa. When both Ki-67 and SMC2 (a core subunit of condensins) were depleted, ball-like chromosome clusters with no sign of discernible thread-like structures were observed. This severe defective phenotype was distinct from that observed in cells depleted of either Ki-67 or SMC2 alone. Our results show that Ki-67 and condensins, which localize to the external surface and the central axis of mitotic chromosomes, respectively, have independent yet cooperative functions in supporting the structural integrity of mitotic chromosomes.


Assuntos
Adenosina Trifosfatases/metabolismo , Cromossomos Humanos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Antígeno Ki-67/metabolismo , Mitose , Complexos Multiproteicos/metabolismo , Adenosina Trifosfatases/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Cromossomos Humanos/genética , Proteínas de Ligação a DNA/genética , Humanos , Ácidos Indolacéticos/metabolismo , Antígeno Ki-67/genética , Complexos Multiproteicos/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transporte Proteico
12.
Genes Cells ; 24(8): 585-590, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31166646

RESUMO

Noncoding (nc) RNA called satellite I is transcribed from the human centromere region. Depletion of this ncRNA results in abnormal nuclear morphology because of defects in chromosome segregation. Some protein factors interact with this ncRNA and function as a component of a nc ribonucleoprotein (RNP) complex in mitotic regulation. Here, we found that DHX38, a pre-mRNA splicing-related DEAH box RNA helicase, interacts with satellite I ncRNA. Depletion of DHX38 resulted in defective chromosome segregation similar to knockdown of satellite I ncRNA. Interaction between DHX38 and ncRNA was interphase-specific, but DHX38 depletion affected the function of Aurora B, which associated with satellite I ncRNA at mitotic phase. Based on these findings, we suggest that DHX38 has a role in mitotic regulation as a component of the satellite I ncRNP complex at interphase.


Assuntos
Centrômero/genética , Segregação de Cromossomos , RNA Helicases DEAD-box/metabolismo , DNA Satélite , Fatores de Processamento de RNA/metabolismo , RNA não Traduzido/genética , Linhagem Celular , Técnicas de Silenciamento de Genes , Humanos
13.
J Nutr ; 150(2): 212-221, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31599944

RESUMO

BACKGROUND: Epidemiological research indicates that iron deficiency (ID) in infancy correlates with long-term cognitive impairment and behavioral disturbances, despite therapy. However, the mechanisms underlying these effects are unknown. OBJECTIVE: We investigated how ID affected postweaning behavior and monoamine concentration in rat brains to determine whether ID during the juvenile period affected gene expression and synapse formation in the prefrontal cortex (PFC) and nucleus accumbens (NAcc). METHODS: Fischer 344/Jcl postweaning male rats aged 21-39 d were fed low-iron diets (0.35 mg/kg iron; ID group) or standard AIN-93 G diets [3.5 mg/kg iron; control (CN) group]. After day 39, all rats were fed the iron-adequate diet. The locomotor activity was evaluated by the open field and elevated plus maze tests at 8 and 12 wk of age. Monoamine concentrations in the brain were analyzed using HPLC at 9 and 13 wk of age. Comprehensive gene expression analysis was performed in the PFC and NAcc at 13 wk of age. Finally, we investigated synaptic density in the PFC and NAcc by synaptophysin immunostaining. RESULTS: Behavioral tests revealed a significant reduction of the age-related decline in the total distance traveled in ID rats compared with CN rats (P < 0.05), indicating that ID affected hyperactivity, which persisted into adulthood (13 wk of age). At this age, reelin (Reln) mRNA expression (adjusted P < 0.01) decreased and synaptic density (P < 0.01) increased in the NAcc in the ID group. Regarding the mesolimbic pathway, homovanillic acid concentration increased in the NAcc, whereas the dopamine concentration decreased in the ventral midbrain. CONCLUSIONS: Our results suggest that ID during the postweaning period in male rats, despite complete iron repletion following ID, led to long-term hyperactivity via monoamine disturbance in the brain and an alteration in the synaptic plasticity accompanied by downregulation of Reln expression in the NAcc.


Assuntos
Anemia Ferropriva/complicações , Atividade Motora , Desmame , Anemia Ferropriva/fisiopatologia , Animais , Monoaminas Biogênicas/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Ratos , Ratos Endogâmicos F344 , Proteína Reelina , Sinapses/metabolismo
14.
FASEB J ; 33(4): 5300-5311, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30681884

RESUMO

Transcriptional and epigenetic regulation is fundamentally involved in initiating and maintaining progression of cellular differentiation. The 2 types of thermogenic adipocytes, brown and beige, are thought to be of different origins but share functionally similar phenotypes. Here, we report that lysine-specific demethylase 2 (LSD2) regulates the expression of genes associated with lineage identity during the differentiation of brown and beige adipogenic progenitors in mice. In HB2 mouse brown preadipocytes, short hairpin RNA-mediated knockdown (KD) of LSD2 impaired formation of lipid droplet-containing adipocytes and down-regulated brown adipogenesis-associated genes. Transcriptomic analysis revealed that myogenesis-associated genes were up-regulated in LSD2-KD cells under adipogenic induction. In addition, loss of LSD2 during later phases of differentiation had no obvious influence on adipogenic traits, suggesting that LSD2 functions during earlier phases of brown adipocyte differentiation. Using adipogenic cells from the brown adipose tissues of LSD2-knockout (KO) mice, we found reduced expression of brown adipogenesis genes, whereas myogenesis genes were not affected. In contrast, when LSD2-KO cells from inguinal white adipose tissues were subjected to beige induction, these cells showed a dramatic rise in myogenic gene expression. Collectively, these results suggest that LSD2 regulates distinct sets of genes during brown and beige adipocyte formation.-Takase, R., Hino, S., Nagaoka, K., Anan, K., Kohrogi, K., Araki, H., Hino, Y., Sakamoto, A., Nicholson, T. B., Chen, T., Nakao, M. Lysine-specific demethylase-2 is distinctively involved in brown and beige adipogenic differentiation.


Assuntos
Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Histona Desmetilases/metabolismo , RNA Interferente Pequeno/metabolismo , Adipogenia/genética , Adipogenia/fisiologia , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Imunoprecipitação da Cromatina , Feminino , Histona Desmetilases/genética , Lentivirus/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR gama/metabolismo , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real
15.
Nucleic Acids Res ; 46(11): 5441-5454, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29618057

RESUMO

The metabolic properties of cells are formed under the influence of environmental factors such as nutrients and hormones. Although such a metabolic program is likely initiated through epigenetic mechanisms, the direct links between metabolic cues and activities of chromatin modifiers remain largely unknown. In this study, we show that lysine-specific demethylase-1 (LSD1) controls the metabolic program in myogenic differentiation, under the action of catabolic hormone, glucocorticoids. By using transcriptomic and epigenomic approaches, we revealed that LSD1 bound to oxidative metabolism and slow-twitch myosin genes, and repressed their expression. Consistent with this, loss of LSD1 activity during differentiation enhanced the oxidative capacity of myotubes. By testing the effects of various hormones, we found that LSD1 levels were decreased by treatment with the glucocorticoid dexamethasone (Dex) in cultured myoblasts and in skeletal muscle from mice. Mechanistically, glucocorticoid signaling induced expression of a ubiquitin E3 ligase, JADE-2, which was responsible for proteasomal degradation of LSD1. Consequently, in differentiating myoblasts, chemical inhibition of LSD1, in combination with Dex treatment, synergistically de-repressed oxidative metabolism genes, concomitant with increased histone H3 lysine 4 methylation at these loci. These findings demonstrated that LSD1 serves as an epigenetic regulator linking glucocorticoid action to metabolic programming during myogenic differentiation.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Histona Desmetilases/metabolismo , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citologia , Animais , Diferenciação Celular/genética , Linhagem Celular Tumoral , Histona Desmetilases/antagonistas & inibidores , Histonas/metabolismo , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Oxirredução , Ubiquitina-Proteína Ligases/metabolismo
16.
J Pathol ; 244(3): 346-357, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29243822

RESUMO

Cancer cells consume a large amount of energy and maintain high levels of anabolism to promote cell proliferation via metabolic reprogramming. Nuclear factor erythroid 2-related factor 2 (Nrf2; NFE2L2) is a master transcription regulator of stress responses and promotes metabolic reprogramming to support cell proliferation in various types of cancer. As oesophageal cancer is one of the most aggressive gastrointestinal cancers, we aimed to clarify the effect of Nrf2 on metabolic reprogramming in oesophageal cancer. The relationship between Nrf2 expression and clinical outcome was evaluated using a database comprising 201 oesophageal cancers. Using in vitro assays and metabolome analysis, we examined the mechanism by which Nrf2 affects malignant phenotype. High-level immunohistochemical expression of Nrf2 was significantly associated with poor recurrence-free survival (HR = 2.67, p = 0.0004) and overall survival (HR = 2.90, p < 0.0001) in oesophageal cancer patients. In an in vitro assay with siRNA in TE-11 cells, which showed high Nrf2 expression, Nrf2 depletion significantly decreased cell growth and enhanced G1 cell cycle arrest and apoptosis. In addition, reactive oxygen species (ROS) were not removed by detoxification via the Nrf2 pathway, with concomitant induction of the p38 mitogen-activated protein kinase pathway. The metabolome analysis showed that Nrf2 strongly promoted metabolic reprogramming to glutathione metabolism, which synthesizes the essential fuels for cancer progression. Furthermore, metabolome analysis using oesophageal cancer specimens confirmed that samples displaying high Nrf2 expression promoted glutathione synthesis. Metabolic reprogramming to glutathione metabolism, and ROS detoxification by activation of Nrf2, enhanced cancer progression and led to a poor clinical outcome in oesophageal cancer patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Proliferação de Células , Metabolismo Energético , Neoplasias Esofágicas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Idoso , Apoptose , Linhagem Celular Tumoral , Bases de Dados Factuais , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular , Glutationa/metabolismo , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Proc Natl Acad Sci U S A ; 113(11): 3054-9, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26929370

RESUMO

Human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes malignant and inflammatory diseases in ∼10% of infected people. A typical host has between 10(4) and 10(5) clones of HTLV-1-infected T lymphocytes, each clone distinguished by the genomic integration site of the single-copy HTLV-1 provirus. The HTLV-1 bZIP (HBZ) factor gene is constitutively expressed from the minus strand of the provirus, whereas plus-strand expression, required for viral propagation to uninfected cells, is suppressed or intermittent in vivo, allowing escape from host immune surveillance. It remains unknown what regulates this pattern of proviral transcription and latency. Here, we show that CTCF, a key regulator of chromatin structure and function, binds to the provirus at a sharp border in epigenetic modifications in the pX region of the HTLV-1 provirus in T cells naturally infected with HTLV-1. CTCF is a zinc-finger protein that binds to an insulator region in genomic DNA and plays a fundamental role in controlling higher order chromatin structure and gene expression in vertebrate cells. We show that CTCF bound to HTLV-1 acts as an enhancer blocker, regulates HTLV-1 mRNA splicing, and forms long-distance interactions with flanking host chromatin. CTCF-binding sites (CTCF-BSs) have been propagated throughout the genome by transposons in certain primate lineages, but CTCF binding has not previously been described in present-day exogenous retroviruses. The presence of an ectopic CTCF-BS introduced by the retrovirus in tens of thousands of genomic locations has the potential to cause widespread abnormalities in host cell chromatin structure and gene expression.


Assuntos
Epigênese Genética , Genoma Humano , Infecções por HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Mutagênese Insercional/genética , Provírus/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Proteínas Virais Reguladoras e Acessórias/genética , Integração Viral/genética , Fatores de Transcrição de Zíper de Leucina Básica/biossíntese , Fatores de Transcrição de Zíper de Leucina Básica/genética , Sítios de Ligação , Fator de Ligação a CCCTC , Linfócitos T CD4-Positivos/virologia , Cromatina/ultraestrutura , Imunoprecipitação da Cromatina , Sequência Consenso , DNA/genética , DNA/metabolismo , Metilação de DNA , DNA Viral/genética , DNA Viral/metabolismo , Regulação Viral da Expressão Gênica , Infecções por HTLV-I/virologia , Código das Histonas , Humanos , Ligação Proteica , Proteínas dos Retroviridae/biossíntese , Proteínas dos Retroviridae/genética , Transcrição Gênica
18.
Hum Mol Genet ; 25(24): 5383-5394, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27798106

RESUMO

Chromatin insulators partition the genome into functional units to control gene expression, particularly in complex chromosomal regions. The CCCTC-binding factor (CTCF) is an insulator-binding protein that functions in transcriptional regulation and higher-order chromatin formation. Variable CTCF-binding sites have been identified to be cell type-specific partly due to differential DNA methylation. Here, we show that DNA methylation-independent removable CTCF insulator is responsible for retinoic acid (RA)-mediated higher-order chromatin remodeling in the human HOXA gene locus. Detailed chromatin analysis characterized multiple CTCF-enriched sites and RA-responsive enhancers at this locus. These regulatory elements and transcriptionally silent HOXA genes are closely positioned under basal conditions. Notably, upon RA signaling, the RAR/RXR transcription factor induced loss of adjacent CTCF binding and changed the higher-order chromatin conformation of the overall locus. Targeted disruption of a CTCF site by genome editing with zinc finger nucleases and CRISPR/Cas9 system showed that the site is required for chromatin conformations that maintain the initial associations among insulators, enhancers and promoters. The results indicate that the initial chromatin conformation affects subsequent RA-induced HOXA gene activation. Our study uncovers that a removable insulator spatiotemporally switches higher-order chromatin and multiple gene activities via cooperation of CTCF and key transcription factors.


Assuntos
Metilação de DNA/genética , Proteínas de Homeodomínio/genética , Proteínas Repressoras/genética , Tretinoína/metabolismo , Fator de Ligação a CCCTC , Sistemas CRISPR-Cas , Linhagem Celular , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , Edição de Genes , Genoma Humano , Proteínas de Homeodomínio/biossíntese , Humanos , Elementos Isolantes/genética , Proteínas Repressoras/metabolismo , Receptor X Retinoide alfa/genética , Transdução de Sinais
19.
Gen Comp Endocrinol ; 260: 58-66, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29277418

RESUMO

Epidemiological research has suggested that birth weights are correlated with adult leg lengths. However, the relationship between prenatal undernutrition (UN) and postnatal leg growth remains controversial. We investigated the effects of UN during early pregnancy on postnatal hindlimb growth and determined whether early embryonic malnutrition affects the functions of postnatal chondrocytes in rats. Undernourished Wistar dams were fed 40% of the daily intake of rats in the control groups from gestational days 5.5-11.5, and femurs, tibias, and trunks or spinal columns were morphologically measured at birth and at 16 weeks of age in control and undernourished offspring of both sexes. We evaluated cell proliferation and differentiation of cultured chondrocytes derived from neonatal tibias of female offspring and determined chondrocyte-related gene expression levels in neonatal epiphysis and embryonic limb buds. Tibial lengths of undernourished female, but not male, offspring were longer at birth and shorter at 16 weeks of age (p < .05) compared with those of control rats. In chondrocyte culture studies, stimulating effects of IGF-1 on cell proliferation (p < .01) were significantly decreased and levels of type II collagen were lower in female undernourished offspring (p < .05). These phenomena were accompanied by decreased expression levels of Col2a1 and Igf1r and increased expression levels of Fgfr3 (p < .05), which might be attributable to the decreased expression of specificity protein 1 (p < .05), a key transactivator of Col2a1 and Igf1r. In conclusion, UN stress during early pregnancy reduces postnatal tibial growth in female offspring by altering the function of chondrocytes, likely reflecting altered expression of gene transactivators.


Assuntos
Desenvolvimento Ósseo/fisiologia , Condrogênese/fisiologia , Desnutrição/fisiopatologia , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Tíbia/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Feminino , Retardo do Crescimento Fetal/etiologia , Idade Gestacional , Masculino , Desnutrição/complicações , Gravidez , Ratos , Ratos Wistar
20.
Bioorg Med Chem Lett ; 27(16): 3862-3866, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28666734

RESUMO

Protein prenylation such as farnesylation and geranylgeranylation is associated with various diseases. Thus, many inhibitors of prenyltransferase have been developed. We report novel inhibitors of farnesyltransferase with a zinc-site recognition moiety and a farnesyl/dodecyl group. Molecular docking analysis showed that both parts of the inhibitor fit well into the catalytic domain of farnesyltransferase. The synthesized inhibitors showed activity against farnesyltransferase in vitro and inhibited proliferation of the pancreatic cell line AsPC-1. Among the compounds with farnesyl and dodecyl groups, the inhibitor with a farnesyl group was found to have stronger and more selective activity.


Assuntos
Inibidores Enzimáticos/farmacologia , Farnesiltranstransferase/antagonistas & inibidores , Compostos Organometálicos/farmacologia , Zinco/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Farnesiltranstransferase/metabolismo , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Relação Estrutura-Atividade , Zinco/química
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