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1.
Adv Gerontol ; 33(2): 313-318, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32593246

RESUMO

The aim of this work was to examine the content of arylhydrocarbon receptor nuclear translocator (ARNT) in fibroblasts of human dermis from 20 weeks of pregnancy until 85 years old, and defining of a role of ARNT in age-dependent changes in the number of fibroblasts in the dermis. ARNT, proliferating cells nuclear antigen (PCNA) were detected with indirect immunohistochemical technique. Results showed that a portion of fibroblasts with positive staining for ARNT in the dermis is decreased from 20 weeks of pregnancy to 40 years old. Percent of ARNT positive fibroblasts in dermis is increased sufficiently since 41 year old until 60-85 years old group. A total number and percent of PCNA positive fibroblasts in dermis decreased with progression of age. Most sufficient age-dependent reduction in a total and PCNA positive number of dermal fibroblast was observed from antenatal until 40 years of life. Age-related changes in the content of ARNT in fibroblasts is not associated with an age-related decrease in total number and percent of PCNA positive fibroblasts the dermis.


Assuntos
Envelhecimento/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Envelhecimento da Pele , Pele/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Derme/citologia , Derme/metabolismo , Feto/metabolismo , Fibroblastos/metabolismo , Humanos , Lactente , Recém-Nascido , Pele/citologia , Adulto Jovem
2.
Ecotoxicol Environ Saf ; 201: 110835, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32563159

RESUMO

The activation of the aryl hydrocarbon receptor (AHR) occurs through the binding of dioxin-like compounds (DLCs) or natural ligands. In this pathway, the AHR-ARNT (AHR nuclear translocator) heterodimer serves to regulate critical physiological functions, such as immune responses and the metabolism of xenobiotics. Birds have three AHR isoforms (AHR1, AHR1ß, and AHR2) and two ARNT isoforms (ARNT1 and ARNT2). However, how AHR and ARNT dimerization pair in birds regulates the AHR signaling pathway in an isoform-specific manner remains unknown. In this study, we initially sought to clarify the major chicken AHR-ARNT (ckAHR-ckARNT) pairs by estimating the mRNA tissue distributions of various ckAHR and ckARNT isoforms. Our results indicated that the ckAHR1-ckARNT1 represented the major dimerization pair in most tissues except the brain. We then measured the transactivation potencies of various ckAHR-ckARNT pairs by natural ligands and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in in vitro reporter gene assays using COS-7 and LMH cell lines. Our results from the in vitro assays demonstrated that the ckAHR1-ckARNT1 pair was strongly activated by the five natural ligands, namely, 6-formylindolo [3,2-b]carbazole, L-kynurenin, kynurenic acid, indoxyl-3-sulfate, and 1,3,7-tribromodibenzo-p-dioxin, but not by TCDD. In in silico ligand docking simulations with ckAHR1 homology models, all the natural ligands showed a interaction pattern that was distinct from that observed with anthropogenic DLCs, including TCDD. In conclusion, our findings indicate that the ckAHR1-ckARNT1 may be the most important dimerization pair in most tissues for regulating the physiological functions driven by natural ligands, although it was less reactive to TCDD.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Galinhas/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Multimerização Proteica , Receptores de Hidrocarboneto Arílico/metabolismo , Xenobióticos/metabolismo , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Simulação por Computador , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Isoformas de Proteínas , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Especificidade da Espécie , Transfecção
3.
Mol Carcinog ; 59(8): 897-907, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32319143

RESUMO

Lactate dehydrogenase isozyme (LDH) is a tetramer constituted of two isoforms, LDHA and LDHB, the expression of which is associated with cell metabolism and cancer progression. Our previous study reveals that CC-chemokine ligand-18 (CCL18) is involved in progression of prostate cancer (PCa).This study aims to investigate how CCL18 regulates LDH isoform expression, and therefore, contributes to PCa progression. The data revealed that the expression of LDHA was upregulated and LDHB was downregulated in PCa cells by CCL18 at both messenger RNA and protein levels. The depletion of CCR8 reduced the ability of CCL18 to promote the proliferation, migration, and lactate production of PCa cells. Depletion of a CCR8 regulated transcription factor, ARNT, significantly reduced the expression of LDHA. In addition, The Cancer Genome Atlas dataset analyses revealed a positive correlation between CCR8 and ARNT expression. Two dimension difference gel electrophoresis revealed that the LDHA/LDHB ratio was increased in the prostatic fluid of patients with PCa and PCa tissues. Furthermore, increased LDHA/LDHB ratio was associated with poor clinical outcomes of patients with PCa. Together, our results indicate that the CCR8 pathway programs LDH isoform expression in an ARNT dependent manner and that the ratio of LDHA/LDHB has the potential to serve as biomarkers for PCa diagnosis and prognosis.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Biomarcadores Tumorais/metabolismo , Quimiocinas CC/metabolismo , Regulação Neoplásica da Expressão Gênica , L-Lactato Desidrogenase/metabolismo , Neoplasias da Próstata/patologia , Receptores CCR8/metabolismo , Apoptose , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Biomarcadores Tumorais/genética , Proliferação de Células , Quimiocinas CC/genética , Humanos , Isoenzimas , L-Lactato Desidrogenase/genética , Masculino , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores CCR8/genética , Taxa de Sobrevida , Células Tumorais Cultivadas
4.
Chemosphere ; 254: 126808, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32339801

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has adverse effects on the development and function of the heart in zebrafish eleutheroembryos (embryos and larvae). We previously reported that TCDD reduced blood flow in the mesencephalic vein of zebrafish eleutheroembryos long before inducing pericardial edema. In the present study, we compared early edema (pre-cardiac edema), reduction of deduced cardiac output and reduction of blood flow in the dorsal aorta and cardinal vein caused by TCDD. In the same group of eleutheroembryos, TCDD (1.0 ppb) caused pre-cardiac edema and circulation failure at the cardinal vein in the central trunk region with the similar time courses from 42 to 54 h post fertilization (hpf), while the same concentration of TCDD did not significantly affect aortic circulation in the central trunk region or cardiac output. The dependence of pre-cardiac edema on TCDD concentration (0-2.0 ppb) at 55 hpf correlated well with the dependence of blood flow through the cardinal vein on TCDD concentration. Several treatments that markedly inhibited TCDD-induced pre-cardiac edema such as knockdown of aryl hydrocarbon receptor nuclear translocator-1 (ARNT1) and treatment with ascorbic acid, an antioxidant, did not significantly prevent the reduction of cardiac output at 55 hpf caused by 2.0 ppb TCDD. TCDD caused hemorrhage and extravasation of Evans blue that was intravascularly injected with bovine serum albumin, suggesting an increase in endothelium permeability to serum protein induced by TCDD. The results suggest that the blood vessels are primary targets of TCDD in edema formation in larval zebrafish.


Assuntos
Dibenzodioxinas Policloradas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Ácido Ascórbico , Edema/induzido quimicamente , Edema Cardíaco/induzido quimicamente , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos , Dibenzodioxinas Policloradas/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
5.
Exp Cell Res ; 388(2): 111845, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31945318

RESUMO

BACKGROUND: Hypoxia-inducible factor (HIF)-2α associates with poor outcome in neuroblastoma and glioblastoma, and gain-of-function mutations in the EPAS1 gene (encoding HIF-2α) have been reported in paragangliomas and pheochromocytomas. Specific targeting of a druggable hydrophobic pocket in the HIF-2α PAS-B domain with PT2385 have demonstrated promising clinical results for clear cell renal cell carcinoma (ccRCC). Here, we investigated the effect of PT2385-mediated inhibition of ARNT dependent HIF-2 activity. METHODS: Neuroblastoma patient-derived xenograft (PDX) cells were treated with PT2385 and analyzed for HIF-2-dependent gene expression, HIF activity, HIF-2α protein localization, response to chemotherapy and orthotopic tumor growth in vivo. Two-sided student t-test was used. RESULTS: We detected high levels of HIF-2α protein in perivascular niches in neuroblastoma PDXs in vivo and at oxygenated conditions in PDX-derived cell cultures in vitro, particularly in the cytoplasmic fraction. Nuclear HIF-2α expression was reduced following PT2385 treatment, but surprisingly, virtually no effects on tumor growth in vivo or expression of canonical HIF downstream target genes in vitro were observed. In coherence, RNA sequencing of PT2385-treated PDX cells revealed a virtually unaffected transcriptome. Treatment with PT2385 did not affect cellular response to chemotherapy. In contrast, HIF-2α protein knockdown resulted in profound downregulation of target genes. CONCLUSIONS: The lack of effect from PT2385 treatment in combination with high cytoplasmic HIF-2α expression at normoxia suggest that HIF-2α have additional roles than acting as an ARNT dependent transcription factor. It is important to further unravel the conditions at which HIF-2α has transcriptional and non-transcriptional roles in neuroblastoma.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Indanos/farmacologia , Neuroblastoma/patologia , Sulfonas/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , Apoptose , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores Tumorais/genética , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neuroblastoma/genética , Neuroblastoma/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Nat Cell Biol ; 22(1): 74-86, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31907414

RESUMO

Collagen is the most abundant secreted protein in vertebrates and persists throughout life without renewal. The permanency of collagen networks contrasts with both the continued synthesis of collagen throughout adulthood and the conventional transcriptional/translational homeostatic mechanisms that replace damaged proteins with new copies. Here, we show circadian clock regulation of endoplasmic reticulum-to-plasma membrane procollagen transport by the sequential rhythmic expression of SEC61, TANGO1, PDE4D and VPS33B. The result is nocturnal procollagen synthesis and daytime collagen fibril assembly in mice. Rhythmic collagen degradation by CTSK maintains collagen homeostasis. This circadian cycle of collagen synthesis and degradation affects a pool of newly synthesized collagen, while maintaining the persistent collagen network. Disabling the circadian clock causes abnormal collagen fibrils and collagen accumulation, which are reduced in vitro by the NR1D1 and CRY1/2 agonists SR9009 and KL001, respectively. In conclusion, our study has identified a circadian clock mechanism of protein homeostasis wherein a sacrificial pool of collagen maintains tissue function.


Assuntos
Relógios Circadianos/fisiologia , Colágeno/metabolismo , Homeostase/fisiologia , Via Secretória/fisiologia , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/efeitos dos fármacos , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Carbazóis/farmacologia , Colágeno/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Matriz Extracelular/metabolismo , Camundongos Transgênicos , Pirrolidinas/farmacologia , Canais de Translocação SEC/efeitos dos fármacos , Canais de Translocação SEC/metabolismo , Via Secretória/genética , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Proteínas de Transporte Vesicular/efeitos dos fármacos , Proteínas de Transporte Vesicular/metabolismo
7.
Nat Prod Res ; 34(6): 893-897, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30445863

RESUMO

This study aims to isolate the potential antiproliferative and cytotoxic compounds from ginkgo biloba sarcotestas (GBS) and investigates the underlying mechanism in human MDA-MB-231 and mouse 4T-1 triple-negative breast cancer cells. Our results showed that 2-Hydroxy-6-tridecylbenzoic acid was isolated by cytotoxicity-guided fractionation where different fractions were assessed using MTT assay against MDA-MB-231 and 4T-1 cells. Colony formation assay showed that 2-Hydroxy-6-tridecylbenzoic acid significantly inhibited cell proliferation. The inhibition was associated with the enhancement of cytochrome P450 (CYP) 1B1 expression in a dose- and time-dependent manner and no significant change of CYP1A1 expression by qPCR and Western blot assays in MDA-MB-231 and 4T-1 cells. The mechanism was further demonstrated by the activation of aryl hydrocarbon receptor (AhR) pathway with the upregulation of AhR, AhR nuclear translocator (ARNT) and AhR-dependent xenobiotic response elements (XRE) activity. These findings may have implications for development of anticancer agents containing 2-Hydroxy-6-tridecylbenzoic acid as functional additives.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Benzoatos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ginkgo biloba/química , Extratos Vegetais/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Benzoatos/uso terapêutico , Linhagem Celular Tumoral , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Feminino , Humanos , Camundongos , Extratos Vegetais/uso terapêutico , Neoplasias de Mama Triplo Negativas/patologia
8.
Chin Med J (Engl) ; 133(2): 148-153, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31868801

RESUMO

BACKGROUND: The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor, which is critically involved in the pathogenesis of a variety of skin diseases. The aim of this study was to detect AhR and its downstream regulators including cytochrome P450 (CYP1A1), AhR nuclear translocation (ARNT), and aryl hydrocarbon receptor repressor (AhRR) in serum, peripheral blood mononuclear cells (PBMCs), and skin lesions in patients with atopic dermatitis (AD). METHODS: Twenty-nine AD patients defined according to the criteria of Hanifin and Rajka and Chinese criteria of AD were included. Subjects without allergic and chronic diseases were recruited as controls. Patients and controls were selected from the dermatology outpatient clinic of Peking University People's Hospital from August 1 to December 31 in 2018. Enzyme-linked immunosorbent assay was performed to detect serum AhR level. The mRNA of AhR, AhRR, ARNT, and CYP1A1 in PBMCs were measured by real-time quantitative polymerase chain reaction. AhR expression in skin lesions was measured by immunohistochemistry. RESULTS: AhR was significantly higher expressed in serum (41.26 ±â€Š4.52 vs. 33.73 ±â€Š2.49 pmol/L, t = 6.507, P < 0.001) and skin lesions (0.191 ±â€Š0.041 vs. 0.087 ±â€Š0.017, t = 10.036, P < 0.001) of AD patients compared with those of controls. The mRNA levels of AhR (1.572 ±â€Š0.392 vs. 1.000 ±â€Š0.173, t = 6.819, P < 0.001), AhRR (2.402 ±â€Š1.716 vs. 1.000 ±â€Š0.788, t = 3.722, P < 0.001), CYP1A1 (2.258 ±â€Š1.598 vs. 1.000 ±â€Š0.796, t = 3.400, P = 0.002) in PBMCs of AD patients were higher compared with those of controls. The difference in mRNA levels of ARNT was not statistically significant between the patients and controls (1.383 ±â€Š0.842 vs. 1.000 ±â€Š0.586, t = 1.653, P = 0.105). AhR mRNA levels in PBMCs positively correlated with eczema area and severity index score and serum interleukin-6 levels. CONCLUSION: AhR and its downstream regulators were highly expressed in serum, PBMCs, and skin of AD patients, which might contribute to the pathogenesis of AD.


Assuntos
Dermatite Atópica/sangue , Dermatite Atópica/metabolismo , Leucócitos Mononucleares/metabolismo , Receptores de Hidrocarboneto Arílico/sangue , Receptores de Hidrocarboneto Arílico/metabolismo , Dermatopatias/sangue , Dermatopatias/metabolismo , Adulto , Idoso , Translocador Nuclear Receptor Aril Hidrocarboneto/sangue , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Sistema Enzimático do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Proteínas Repressoras/sangue , Proteínas Repressoras/metabolismo
9.
Nat Commun ; 10(1): 4579, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31594926

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by progressive bone erosion. Leflunomide is originally developed to suppress inflammation via its metabolite A77 1726 to attenuate bone erosion. However, distinctive responsiveness to Leflunomide is observed among RA individuals. Here we show that Leflunomide exerts immunosuppression but limited efficacy in RA individuals distinguished by higher serum C-reactive protein (CRPHigher, CRPH), whereas the others with satisfactory responsiveness to Leflunomide show lower CRP (CRPLower, CRPL). CRP inhibition decreases bone erosion in arthritic rats. Besides the immunomodulation via A77 1726, Leflunomide itself induces AHR-ARNT interaction to inhibit hepatic CRP production and attenuate bone erosion in CRPL arthritic rats. Nevertheless, high CRP in CRPH rats upregulates HIF1α, which competes with AHR for ARNT association and interferes Leflunomide-AHR-CRP signaling. Hepatocyte-specific HIF1α deletion or a HIF1α inhibitor Acriflavine re-activates Leflunomide-AHR-CRP signaling to inhibit bone erosion. This study presents a precision medicine-based therapeutic strategy for RA.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Imunossupressores/farmacologia , Leflunomida/farmacologia , Acriflavina/farmacologia , Acriflavina/uso terapêutico , Adulto , Animais , Artrite Experimental/sangue , Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Reabsorção Óssea/sangue , Reabsorção Óssea/imunologia , Proteína C-Reativa/análise , Proteína C-Reativa/imunologia , Proteína C-Reativa/metabolismo , Células Cultivadas , Colágeno/imunologia , Feminino , Hepatócitos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Imunossupressores/uso terapêutico , Leflunomida/uso terapêutico , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Ratos , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Resultado do Tratamento
10.
Endocrinology ; 160(12): 2825-2836, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31580427

RESUMO

The transcription factor aryl hydrocarbon receptor nuclear translocator (ARNT)/hypoxia-inducible factor (HIF)-1ß (ARNT/HIF1ß) plays a key role in maintaining ß-cell function and has been shown to be one of the most downregulated transcription factors in islets from patients with type 2 diabetes. We have shown a role for ARNT/HIF1ß in glucose sensing and insulin secretion in vitro and no defects in in vivo glucose homeostasis. To gain a better understanding of the role of ARNT/HIF1ß in the development of diabetes, we placed control (+/+/Cre) and ß-cell-specific ARNT/HIF1ß knockout (fl/fl/Cre) mice on a high-fat diet (HFD). Unlike the control (+/+/Cre) mice, HFD-fed fl/fl/Cre mice had no impairment in in vivo glucose tolerance. The lack of impairment in HFD-fed fl/fl/Cre mice was partly due to an improved islet glucose-stimulated NADPH/NADP+ ratio and glucose-stimulated insulin secretion. The effects of the HFD-rescued insulin secretion in fl/fl/Cre islets could be reproduced by treating low-fat diet (LFD)-fed fl/fl/Cre islets with the lipid signaling molecule 1-monoacylglcyerol. This suggests that the defects seen in LFD-fed fl/fl/Cre islet insulin secretion involve lipid signaling molecules. Overall, mice lacking ARNT/HIF1ß in ß-cells have altered lipid signaling in vivo and are resistant to an HFD's ability to induce diabetes.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Diabetes Mellitus Experimental/metabolismo , Células Secretoras de Insulina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Diabetes Mellitus Experimental/etiologia , Dieta Hiperlipídica , Diglicerídeos , Glucose/metabolismo , Homeostase , Secreção de Insulina , Masculino , Camundongos Knockout , NADP/metabolismo
11.
Int J Mol Sci ; 20(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547315

RESUMO

Nicotine is one of the most toxic secondary plant metabolites in nature and it is highly toxic to herbivorous insects. The overexpression of CYP6CY3 and its homologous isozyme CYP6CY4 in Myzus persicae nicotianae is correlated with nicotine tolerance. The expanded (AC)n repeat in promoter is the cis element for CYP6CY3 transcription. These repeat sequences are conserved in the CYP6CY3 gene from Aphis gossypii and the homologous P450 genes in Acyrthosiphon pisum. The potential transcriptional factors that may regulate CYP6CY3 were isolated by DNA pulldown and sequenced in order to investigate the underlying transcriptional regulation mechanism of CYP6CY3. These identified transcriptional factors, AhR and ARNT, whose abundance was highly correlated with an abundance of the CYP6CY3 gene, were validated. RNAi and co-transfection results further confirm that AhR and ARNT play a major role in the transcriptional regulation of the CYP6CY3 gene. When the CYP6CY3 transcript is destabilized by AhR/ARNT RNAi, the transcription of the CYP6CY4 is dramatically up-regulated, indicating a compensatory mechanism between the CYP6CY3 and CYP6CY4 genes. Our present study sheds light on the CYP6CY3 and CYP6CY4 mediated nicotine adaption of M. persicae nicotianae to tobacco. The current studies shed light on the molecular mechanisms that underlie the genotypic and phenotypic changes that are involved in insect host shifts and we conclude that AhR/ARNT regulate the expression of CYP6CY3 and CYP6CY4 cooperatively, conferring the nicotine adaption of M. persicae nicotianae to tobacco.


Assuntos
Afídeos/fisiologia , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Família 6 do Citocromo P450/metabolismo , Proteínas de Insetos/metabolismo , Nicotina/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Adaptação Fisiológica , Animais , Afídeos/genética , Família 6 do Citocromo P450/genética , Interações Hospedeiro-Parasita , Proteínas de Insetos/genética , Tabaco/metabolismo , Tabaco/parasitologia , Ativação Transcricional
12.
JCI Insight ; 4(15)2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31391338

RESUMO

Despite the propensity for gastric and esophageal adenocarcinomas to select for recurrent missense mutations in TP53, the precise functional consequence of these mutations remains unclear. Here we report that endogenous mRNA and protein levels of mutant p53 were elevated in cell lines and patients with gastric and esophageal cancer. Functional studies showed that mutant p53 was sufficient, but not necessary, for enhancing primary tumor growth in vivo. Unbiased genome-wide transcriptome analysis revealed that hypoxia signaling was induced by mutant p53 in 2 gastric cancer cell lines. Using real-time in vivo imaging, we confirmed that hypoxia reporter activity was elevated during the initiation of mutant p53 gastric cancer xenografts. Unlike HIF co-factor ARNT, HIF1α was required for primary tumor growth in mutant p53 gastric cancer. These findings elucidate the contribution of missense p53 mutations in gastroesophageal malignancy and indicate that hypoxia signaling rather than mutant p53 itself may serve as a therapeutic vulnerability in these deadly set of cancers.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Adenocarcinoma/patologia , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Carcinogênese/genética , Hipóxia Celular/genética , Linhagem Celular Tumoral , Análise Mutacional de DNA , Conjuntos de Dados como Assunto , Mucosa Esofágica/patologia , Neoplasias Esofágicas/patologia , Mucosa Gástrica/patologia , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Microscopia Intravital , Camundongos , Mutação de Sentido Incorreto , Transdução de Sinais/genética , Neoplasias Gástricas/patologia , Transcrição Genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Infect Immun ; 87(11)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31451620

RESUMO

Cutaneous leishmaniasis is characterized by vascular remodeling. Following infection with Leishmania parasites, the vascular endothelial growth factor A (VEGF-A)/VEGF receptor 2 (VEGFR-2) signaling pathway mediates lymphangiogenesis, which is critical for lesion resolution. Therefore, we investigated the cellular and molecular mediators involved in VEGF-A/VEGFR-2 signaling using a murine model of infection. We found that macrophages are the predominant cell type expressing VEGF-A during Leishmania major infection. Given that Leishmania parasites activate hypoxia-inducible factor 1α (HIF-1α) and this transcription factor can drive VEGF-A expression, we analyzed the expression of HIF-1α during infection. We showed that macrophages were also the major cell type expressing HIF-1α during infection and that infection-induced VEGF-A production is mediated by ARNT/HIF activation. Furthermore, mice deficient in myeloid ARNT/HIF signaling exhibited larger lesions without differences in parasite numbers. These data show that L. major infection induces macrophage VEGF-A production in an ARNT/HIF-dependent manner and suggest that ARNT/HIF signaling may limit inflammation by promoting VEGF-A production and, thus, lymphangiogenesis during infection.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Leishmaniose Cutânea/metabolismo , Macrófagos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Células Cultivadas , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Leishmania major , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Pele/metabolismo , Pele/parasitologia , Fator A de Crescimento do Endotélio Vascular/genética
14.
PLoS One ; 14(6): e0217906, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31158257

RESUMO

Understanding the transcriptional pathways controlling tissue-specific gene expression is critical to unraveling the complex regulatory networks that underlie developmental mechanisms. Here, we assessed how the Drosophila crossveinless (cv) gene, that encodes a BMP-binding factor, is transcriptionally regulated in the developing embryonic tracheal system. We identify an upstream regulatory region of cv that promotes reporter gene expression in the tracheal precursors. We further demonstrate that this promoter region is directly responsive to the basic, helix-loop-helix-PAS domain factors Trachealess (Trh) and Tango (Tgo), that function to specify tracheal fate. Moreover, cv expression in embryos is lost in trh mutants, and the integrity of the Trh/Tgo binding sites are required for promoter-lacZ expression. These findings for the first time elucidate the transcriptional regulation of one member of a family of BMP binding proteins, that have diverse functions in animal development.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Traqueia/citologia , Fatores de Transcrição/metabolismo , Transcrição Genética , Animais , Animais Geneticamente Modificados , Sequência de Bases , Proteínas de Drosophila/genética , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica no Desenvolvimento , Loci Gênicos , Regiões Promotoras Genéticas/genética
15.
Clin Sci (Lond) ; 133(12): 1353-1365, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31189688

RESUMO

Pregnancies complicated by severe fetal growth restriction with abnormal umbilical artery Doppler velocimetry (FGRadv) are at substantial risk for adverse perinatal and long-term outcomes. Impaired angiogenesis of the placental vasculature in these pregnancies results in a sparse, poorly branched vascular tree, which structurally contributes to the abnormally elevated fetoplacental vascular resistance that is clinically manifested by absent or reversed umbilical artery Doppler indices. Previous studies have shown that aryl hydrocarbon receptor nuclear translocator (ARNT) is a key mediator of proper placental angiogenesis, and within placental endothelial cells (ECs) from human FGRadv pregnancies, low expression of ARNT leads to decreased vascular endothelial growth factor A (VEGFA) expression and deficient tube formation. Thus, the aim of the present study was to determine the effect of VEGFA administration or ARNT overexpression on angiogenic potential of FGRadv ECs. ECs were isolated and cultured from FGRadv or gestational age-matched control placentas and subjected to either vehicle vs VEGFA treatment or transduction with adenoviral-CMV (ad-CMV) vs adenoviral-ARNT (ad-ARNT) constructs. They were then assessed via wound scratch and tube formation assays. We found that VEGFA administration nominally improved FGRadv EC migration (P<0.01) and tube formation (P<0.05). ARNT overexpression led to significantly enhanced ARNT expression in FGRadv ECs (P<0.01), to a level similar to control ECs. Despite this, FGRadv EC migration (P<0.05) and tube formation (P<0.05) were still only partially rescued. This suggests that although ARNT does play a role in fetoplacental EC migration, other factors in addition to ARNT are likely also important in placental angiogenesis.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Células Endoteliais/metabolismo , Retardo do Crescimento Fetal/metabolismo , Neovascularização Patológica , Placenta/irrigação sanguínea , Adulto , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Estudos de Casos e Controles , Movimento Celular , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/patologia , Retardo do Crescimento Fetal/fisiopatologia , Humanos , Gravidez , Transdução de Sinais , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
16.
Nucleic Acids Res ; 47(13): 6842-6857, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31175824

RESUMO

Although transposable elements are an important source of regulatory variation, their genome-wide contribution to the transcriptional regulation of stress-response genes has not been studied yet. Stress is a major aspect of natural selection in the wild, leading to changes in the transcriptional regulation of a variety of genes that are often triggered by one or a few transcription factors. In this work, we take advantage of the wealth of information available for Drosophila melanogaster and humans to analyze the role of transposable elements in six stress regulatory networks: immune, hypoxia, oxidative, xenobiotic, heat shock, and heavy metal. We found that transposable elements were enriched for caudal, dorsal, HSF, and tango binding sites in D. melanogaster and for NFE2L2 binding sites in humans. Taking into account the D. melanogaster population frequencies of transposable elements with predicted binding motifs and/or binding sites, we showed that those containing three or more binding motifs/sites are more likely to be functional. For a representative subset of these TEs, we performed in vivo transgenic reporter assays in different stress conditions. Overall, our results showed that TEs are relevant contributors to the transcriptional regulation of stress-response genes.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Regulação da Expressão Gênica/genética , Genes de Insetos , Estresse Fisiológico/genética , Transcrição Genética/genética , Motivos de Aminoácidos , Animais , Animais Geneticamente Modificados , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Sítios de Ligação , Imunoprecipitação da Cromatina , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/embriologia , Drosophila melanogaster/imunologia , Feminino , Redes Reguladoras de Genes , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Ligação Proteica , Especificidade da Espécie , Fatores de Transcrição/metabolismo
17.
Int J Mol Sci ; 20(12)2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31238581

RESUMO

MicroRNAs (miRNAs) have been determined to be important regulators for pathogenic microorganism infection. However, it is largely unclear how miRNAs are triggered during pathogen infection. We previously reported that the up-regulation of gga-miR-451 negatively regulates the Mycoplasma gallisepticum (MG)-induced production of inflammatory cytokines via targeting tyrosine3-monooxygenase/tryptophan5-monooxygenase activation protein zeta (YWHAZ). The aim of this study was to investigate the mechanism regulating gga-miR-451 in MG infection in chickens. Analysis of gga-miR-451 precursor, pri-miR-451, and pre-miR-451 indicated that the regulation occurred transcriptionally. We also identified the transcriptional regulatory region of gga-miR-451 that contained consensus-binding motif for aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (Arnt) complex, which is known as the transcription factor that regulates gene expression. Luciferase reporter assays combined with chromatin immunoprecipitation (ChIP) demonstrated that AhR:Arnt bound directly to the promoter elements of gga-miR-451, which were responsible for gga-miR-451 transcription in the context of MG infection. Furthermore, upregulation of AhR:Arnt significantly induced gga-miR-451 and inhibited YWHAZ expression, suggesting that AhR:Arnt may play an anti-inflammatory role in MG infection. This discovery suggests that induced gga-miR-451 expression is modulated by AhR:Arnt in response to MG infection.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Interações Hospedeiro-Patógeno/genética , MicroRNAs/genética , Infecções por Mycoplasma/genética , Infecções por Mycoplasma/metabolismo , Mycoplasma gallisepticum , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Embrião de Galinha , Fibroblastos , Regulação da Expressão Gênica , Infecções por Mycoplasma/microbiologia , Ativação Transcricional
18.
J Biochem ; 166(2): 115-119, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31098622

RESUMO

Proteins synthesized within the endoplasmic reticulum (ER) are exported from ER exit sites via coat protein complex II (COPII)-coated vesicles. Although the mechanisms of COPII-vesicle formation at the ER exit sites are highly conserved among species, vertebrate cells secrete a wide range of materials, including collagens and chylomicrons, which form bulky structures within the ER that are too large to fit into conventional carriers. Transport ANd Golgi Organization 1 (TANGO1) was initially identified as a cargo receptor for collagens but has been recently rediscovered as an organizer of ER exit sites. We would like to review recent advances in the mechanism of large cargo secretion and organization of ER exit sites through the function of TANGO1.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Retículo Endoplasmático/metabolismo , Animais , Drosophila , Proteínas de Drosophila/metabolismo , Humanos
19.
Sci Rep ; 9(1): 7346, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089171

RESUMO

Secretory proteins are exported from special domains of the endoplasmic reticulum (ER) termed ER exit sites, via COPII-coated carriers. We recently showed that TANGO1 and Sec16 cooperatively organize mammalian ER exit sites for efficient secretion. However, the detailed spatial organization of mammalian ER exit sites is yet to be revealed. Here, we used super-resolution confocal live imaging microscopy (SCLIM) to investigate the localization of endogenous proteins, and we identified domains abundant in transmembrane complexes (TANGO1/cTAGE5/Sec12) juxtaposed to Sec16. Interestingly, this domain can be distinguished from the inner and the outer coats of COPII proteins within each mammalian ER exit site. Cargoes are partially concentrated in the domain for secretion. Our results suggest that mammalian ER exit sites compartmentalize proteins according to their function in COPII vesicle formation.


Assuntos
Antígenos de Neoplasias/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/metabolismo , Proteínas de Ligação a DNA/metabolismo , Retículo Endoplasmático/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição/metabolismo , Antígenos de Neoplasias/análise , Translocador Nuclear Receptor Aril Hidrocarboneto/análise , Proteínas de Ligação a DNA/análise , Fatores de Troca do Nucleotídeo Guanina/análise , Células HeLa , Humanos , Proteínas de Neoplasias/análise , Domínios Proteicos , Fatores de Transcrição/análise
20.
Neuron ; 102(2): 390-406.e9, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30846309

RESUMO

Neuronal activity-dependent transcription is tuned to ensure precise gene induction during periods of heightened synaptic activity, allowing for appropriate responses of activated neurons within neural circuits. The consequences of aberrant induction of activity-dependent genes on neuronal physiology are not yet clear. Here, we demonstrate that, in the absence of synaptic excitation, the basic-helix-loop-helix (bHLH)-PAS family transcription factor ARNT2 recruits the NCoR2 co-repressor complex to suppress neuronal activity-dependent regulatory elements and maintain low basal levels of inducible genes. This restricts inhibition of excitatory neurons, maintaining them in a state that is receptive to future sensory stimuli. By contrast, in response to heightened neuronal activity, ARNT2 recruits the neuronal-specific bHLH-PAS factor NPAS4 to activity-dependent regulatory elements to induce transcription and thereby increase somatic inhibitory input. Thus, the interplay of bHLH-PAS complexes at activity-dependent regulatory elements maintains temporal control of activity-dependent gene expression and scales somatic inhibition with circuit activity.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica , Neurônios/metabolismo , Correpressor 2 de Receptor Nuclear/metabolismo , Animais , Camundongos , Inibição Neural , Elementos Reguladores de Transcrição , Ativação Transcricional
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