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1.
Nat Commun ; 12(1): 5068, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417460

RESUMO

p53 regulates several signaling pathways to maintain the metabolic homeostasis of cells and modulates the cellular response to stress. Deficiency or excess of nutrients causes cellular metabolic stress, and we hypothesized that p53 could be linked to glucose maintenance. We show here that upon starvation hepatic p53 is stabilized by O-GlcNAcylation and plays an essential role in the physiological regulation of glucose homeostasis. More specifically, p53 binds to PCK1 promoter and regulates its transcriptional activation, thereby controlling hepatic glucose production. Mice lacking p53 in the liver show a reduced gluconeogenic response during calorie restriction. Glucagon, adrenaline and glucocorticoids augment protein levels of p53, and administration of these hormones to p53 deficient human hepatocytes and to liver-specific p53 deficient mice fails to increase glucose levels. Moreover, insulin decreases p53 levels, and over-expression of p53 impairs insulin sensitivity. Finally, protein levels of p53, as well as genes responsible of O-GlcNAcylation are elevated in the liver of type 2 diabetic patients and positively correlate with glucose and HOMA-IR. Overall these results indicate that the O-GlcNAcylation of p53 plays an unsuspected key role regulating in vivo glucose homeostasis.


Assuntos
Acetilglucosamina/metabolismo , Glucose/metabolismo , Fígado/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Sequência de Bases , Restrição Calórica , Linhagem Celular , Colforsina/farmacologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Epinefrina/metabolismo , Glucagon/metabolismo , Glucocorticoides/metabolismo , Gluconeogênese/efeitos dos fármacos , Glicosilação , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hidrocortisona/metabolismo , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Resistência à Insulina , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/complicações , Obesidade/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Ácido Pirúvico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
2.
Nat Commun ; 12(1): 5071, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417470

RESUMO

Identification of causal variants and genes underlying genome-wide association study (GWAS) loci is essential to understand the biology of alcohol use disorder (AUD) and drinks per week (DPW). Multi-omics integration approaches have shown potential for fine mapping complex loci to obtain biological insights to disease mechanisms. In this study, we use multi-omics approaches, to fine-map AUD and DPW associations at single SNP resolution to demonstrate that rs56030824 on chromosome 11 significantly reduces SPI1 mRNA expression in myeloid cells and lowers risk for AUD and DPW. Our analysis also identifies MAPT as a candidate causal gene specifically associated with DPW. Genes prioritized in this study show overlap with causal genes associated with neurodegenerative disorders. Multi-omics integration analyses highlight, genetic similarities and differences between alcohol intake and disordered drinking, suggesting molecular heterogeneity that might inform future targeted functional and cross-species studies.


Assuntos
Alcoolismo/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genômica , Doenças Neurodegenerativas/genética , Encéfalo/metabolismo , Epigênese Genética , Feto/metabolismo , Redes Reguladoras de Genes , Loci Gênicos , Marcadores Genéticos , Humanos , Desequilíbrio de Ligação/genética , Análise da Randomização Mendeliana , Mapeamento Físico do Cromossomo , Regiões Promotoras Genéticas/genética , Locos de Características Quantitativas/genética
3.
FASEB J ; 35(9): e21833, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365659

RESUMO

Macrophages are the principal component of the innate immune system. They play very crucial and multifaceted roles in the pathogenesis of inflammatory vascular diseases. There is an increasing recognition that transcriptionally dynamic macrophages are the key players in the pathogenesis of inflammatory vascular diseases. In this context, the accumulation and aberrant activation of macrophages in the subendothelial layers govern atherosclerotic plaque development. Macrophage-mediated inflammation is an explicitly robust biological response that involves broad alterations in inflammatory gene expression. Thus, cell-intrinsic negative regulatory mechanisms must exist which can restrain inflammatory response in a spatiotemporal manner. In this study, we identified CBP/p300-interacting transactivator with glutamic acid/aspartic acid-rich carboxyl-terminal domain 2 (CITED2) as one such cell-intrinsic negative regulator of inflammation. Our in vivo studies show that myeloid-CITED2-deficient mice on the Apoe-/- background have larger atherosclerotic lesions on both control and high-fat/high-cholesterol diets. Our integrated transcriptomics and gene set enrichment analyses studies show that CITED2 deficiency elevates STAT1 and interferon regulatory factor 1 (IRF1) regulated pro-inflammatory gene expression in macrophages. At the molecular level, our studies identify that CITED2 deficiency elevates IFNγ-induced STAT1 transcriptional activity and STAT1 enrichment on IRF1 promoter in macrophages. More importantly, siRNA-mediated knockdown of IRF1 completely reversed elevated pro-inflammatory target gene expression in CITED2-deficient macrophages. Collectively, our study findings demonstrate that CITED2 restrains the STAT1-IRF1 signaling axis in macrophages and limits the development of atherosclerotic plaques.


Assuntos
Aterosclerose/genética , Fator Regulador 1 de Interferon/genética , Proteínas Repressoras/genética , Fator de Transcrição STAT1/genética , Transdução de Sinais/genética , Transativadores/genética , Animais , Feminino , Inflamação/genética , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Células RAW 264.7 , Transcrição Genética/genética
4.
FASEB J ; 35(9): e21827, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383980

RESUMO

Neuron-derived orphan receptor 1, NR4A3 (Nor1)/NR4A3 is an orphan nuclear receptor involved in the transcriptional control of developmental and neurological functions. Oxidative stress-induced conditions are primarily associated with neurological defects in humans, yet the impact on Nor1-mediated transcription of neuronal genes remains with unknown mechanism. Here, we demonstrate that Nor1 is a non-conventional target of SUMO2/3 conjugation at Lys-137 contained in an atypic ψKxSP motif referred to as the pSuM. Nor1 pSuM SUMOylation differs from the canonical process with the obligate phosphorylation of Ser-139 by Ras signaling to create the required negatively charged interface for SUMOylation. Additional phosphorylation at sites flanking the pSuM is also mediated by the coordinated action of protein kinase casein kinase 2 to function as a small ubiquitin-like modifier enhancer, regulating Nor1-mediated transcription and proteasomal degradation. Nor1 responsive genes involved in cell proliferation and metabolism, such as activating transcription factor 3, cyclin D1, CASP8 and FADD-like apoptosis regulator, and enolase 3 were upregulated in response to pSuM disruption in mouse HT-22 hippocampal neuronal cells and human neuroblastoma SH-SY5Y cells. We also identified critical antioxidant genes, such as catalase, superoxide dismutase 1, and microsomal glutathione S-transferase 2, as responsive targets of Nor1 under pSuM regulation. Nor1 SUMOylation impaired gene transcription through less effective Nor1 chromatin binding and reduced enrichment of histone H3K27ac marks to gene promoters. These effects resulted in decreased neuronal cell growth, increased apoptosis, and reduced survival to oxidative stress damage, underlying the role of pSuM-modified Nor1 in redox homeostasis. Our findings uncover a hierarchical post-translational mechanism that dictates Nor1 non-canonical SUMOylation, disrupting Nor1 transcriptional competence, and neuroprotective redox sensitivity.


Assuntos
Sobrevivência Celular/genética , Proteínas de Ligação a DNA/genética , Receptores de Esteroides/genética , Receptores dos Hormônios Tireóideos/genética , Sumoilação/genética , Animais , Apoptose/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Quinase do Ponto de Checagem 2/genética , Regulação da Expressão Gênica/genética , Células HEK293 , Hipocampo/metabolismo , Homeostase/genética , Humanos , Camundongos , Neuroblastoma/genética , Neurônios/metabolismo , Oxirredução , Estresse Oxidativo/genética , Fosforilação/genética , Regiões Promotoras Genéticas/genética , Processamento de Proteína Pós-Traducional/genética , Transcrição Genética/genética , Ativação Transcricional/genética , Regulação para Cima/genética
5.
Nat Immunol ; 22(9): 1107-1117, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34385713

RESUMO

The linkage between neutrophil death and the development of autoimmunity has not been thoroughly explored. Here, we show that neutrophils from either lupus-prone mice or patients with systemic lupus erythematosus (SLE) undergo ferroptosis. Mechanistically, autoantibodies and interferon-α present in the serum induce neutrophil ferroptosis through enhanced binding of the transcriptional repressor CREMα to the glutathione peroxidase 4 (Gpx4, the key ferroptosis regulator) promoter, which leads to suppressed expression of Gpx4 and subsequent elevation of lipid-reactive oxygen species. Moreover, the findings that mice with neutrophil-specific Gpx4 haploinsufficiency recapitulate key clinical features of human SLE, including autoantibodies, neutropenia, skin lesions and proteinuria, and that the treatment with a specific ferroptosis inhibitor significantly ameliorates disease severity in lupus-prone mice reveal the role of neutrophil ferroptosis in lupus pathogenesis. Together, our data demonstrate that neutrophil ferroptosis is an important driver of neutropenia in SLE and heavily contributes to disease manifestations.


Assuntos
Ferroptose/fisiologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Neutropenia/patologia , Neutrófilos/imunologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Autoanticorpos/imunologia , Autoimunidade/imunologia , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Humanos , Interferon-alfa/imunologia , Camundongos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Regiões Promotoras Genéticas/genética , Espécies Reativas de Oxigênio/metabolismo
6.
FASEB J ; 35(9): e21667, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34405442

RESUMO

Long noncoding RNAs (lncRNAs) are central regulators of the inflammatory response and play an important role in inflammatory diseases. PINT has been reported to be involved in embryonic development and tumorigenesis. However, the potential functions of PINT in the innate immune system are largely unknown. Here, we revealed the transcriptional regulation of inflammatory genes by PINT, whose expression is primarily dependent on the NF-κB signaling pathway in human and mouse macrophage and intestinal epithelial cell lines. Functionally, PINT selectively regulates the expression of TNF-α in basal and LPS-stimulated cells. Mechanistically, PINT acts as a modular scaffold of p65 and EZH2 to coordinate their localization and specify their binding to the target genes. Further, a high expression level of PINT was detected in intestinal mucosal tissues from patients with ulcerative colitis (UC). Together, these findings demonstrate that PINT acts as an activator of inflammatory responses, highlighting the importance of this lncRNA as a potential therapeutic target in infectious diseases and inflammatory diseases.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação da Expressão Gênica , RNA Longo não Codificante/genética , Fator de Transcrição RelA/metabolismo , Transcrição Genética , Fator de Necrose Tumoral alfa/genética , Animais , Linhagem Celular , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Citocinas/genética , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transcrição Genética/genética
7.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443682

RESUMO

Atherosclerosis is the main cause of cardiovascular diseases which in turn, lead to the highest number of mortalities globally. This pathophysiological condition is developed due to a constant elevated level of plasma cholesterols. Statin is currently the widely used treatment in reducing the level of cholesterols, however, it may cause adverse side effects. Therefore, there is an urgent need to search for new alternative treatment. PCSK9 is an enzyme responsible in directing LDL-receptor (LDL-R)/LDL-cholesterols (LDL-C) complex to lysosomal degradation, preventing the receptor from recycling back to the surface of liver cells. Therefore, PCSK9 offers a potential target to search for small molecule inhibitors which inhibit the function of this enzyme. In this study, a marine invertebrate Acanthaster planci, was used to investigate its potential in inhibiting PCSK9 and lowering the levels of cholesterols. Cytotoxicity activity of A. planci on human liver HepG2 cells was carried out using the MTS assay. It was found that methanolic extract and fractions did not exhibit cytotoxicity effect on HepG2 cell line with IC50 values of more than 30 µg/mL. A compound deoxythymidine also did not exert any cytotoxicity activity with IC50 value of more than 4 µg/mL. Transient transfection and luciferase assay were conducted to determine the effects of A. planci on the transcriptional activity of PCSK9 promoter. Methanolic extract and Fraction 2 (EF2) produced the lowest reduction in PCSK9 promoter activity to 70 and 20% of control at 12.5 and 6.25 µg/mL, respectively. In addition, deoxythymidine also decreased PCSK9 promoter activity to the lowest level of 60% control at 3.13 µM. An in vivo study using Sprague Dawley rats demonstrated that 50 and 100 mg/kg of A. planci methanolic extract reduced the total cholesterols and LDL-C levels to almost similar levels of untreated controls. The level of serum glutamate oxalate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) showed that the administration of the extract did not produce any toxicity effect and cause any damage to rat liver. The results strongly indicate that A. planci produced a significant inhibitory activity on PCSK9 gene expression in HepG2 cells which may be responsible for inducing the uptake of cholesterols by liver, thus, reducing the circulating levels of total cholesterols and LDL-C. Interestingly, A. planci also did show any adverse hepato-cytotoxicity and toxic effects on liver. Thus, this study strongly suggests that A. planci has a vast potential to be further developed as a new class of therapeutic agent in lowering the blood cholesterols and reducing the progression of atherosclerosis.


Assuntos
Colesterol/sangue , Pró-Proteína Convertase 9/antagonistas & inibidores , Estrelas-do-Mar/química , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Morte Celular , Proliferação de Células , LDL-Colesterol/sangue , Células Hep G2 , Humanos , Luciferases/metabolismo , Masculino , Metanol , Regiões Promotoras Genéticas/genética , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Ratos Sprague-Dawley , Timidina/farmacologia , Triglicerídeos/sangue
8.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445115

RESUMO

The SWEET (Sugars Will Eventually be Exported Transporter) proteins are a novel family of sugar transporters that play key roles in sugar efflux, signal transduction, plant growth and development, plant-pathogen interactions, and stress tolerance. In this study, 22 ClaSWEET genes were identified in Citrullus lanatus (Thunb.) through homology searches and classified into four groups by phylogenetic analysis. The genes with similar structures, conserved domains, and motifs were clustered into the same groups. Further analysis of the gene promoter regions uncovered various growth, development, and biotic and abiotic stress responsive cis-regulatory elements. Tissue-specific analysis showed most of the genes were highly expressed in male flowers and the roots of cultivated varieties and wild cultivars. In addition, qRT-PCR results further imply that ClaSWEET proteins might be involved in resistance to Fusarium oxysporum infection. Moreover, a significantly higher expression level of these genes under various abiotic stresses suggests its multifaceted role in mediating plant responses to drought, salt, and low-temperature stress. The genome-wide characterization and phylogenetic analysis of ClaSWEET genes, together with the expression patterns in different tissues and stimuli, lays a solid foundation for future research into their molecular function in watermelon developmental processes and responses to biotic and abiotic stresses.


Assuntos
Transporte Biológico/genética , Citrullus/genética , Genoma de Planta/genética , Família Multigênica/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Açúcares/metabolismo , Fusarium/genética , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla/métodos , Filogenia , Raízes de Plantas/genética , Regiões Promotoras Genéticas/genética
9.
Nat Commun ; 12(1): 4929, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389727

RESUMO

Synthetic metabolic pathways are a burden for engineered bacteria, but the underlying mechanisms often remain elusive. Here we show that the misregulated activity of the transcription factor Cra is responsible for the growth burden of glycerol overproducing E. coli. Glycerol production decreases the concentration of fructose-1,6-bisphoshate (FBP), which then activates Cra resulting in the downregulation of glycolytic enzymes and upregulation of gluconeogenesis enzymes. Because cells grow on glucose, the improper activation of gluconeogenesis and the concomitant inhibition of glycolysis likely impairs growth at higher induction of the glycerol pathway. We solve this misregulation by engineering a Cra-binding site in the promoter controlling the expression of the rate limiting enzyme of the glycerol pathway to maintain FBP levels sufficiently high. We show the broad applicability of this approach by engineering Cra-dependent regulation into a set of constitutive and inducible promoters, and use one of them to overproduce carotenoids in E. coli.


Assuntos
Escherichia coli/genética , Glicólise/genética , Engenharia Metabólica/métodos , Metabolômica/métodos , Proteômica/métodos , Transcrição Genética , Algoritmos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Carotenoides/metabolismo , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Modelos Genéticos , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Nat Commun ; 12(1): 4897, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385432

RESUMO

Precise control of mammalian gene expression is facilitated through epigenetic mechanisms and nuclear organization. In particular, insulated chromosome structures are important for regulatory control, but the phenotypic consequences of their boundary disruption on developmental processes are complex and remain insufficiently understood. Here, we generated deeply sequenced Hi-C data for human pluripotent stem cells (hPSCs) that allowed us to identify CTCF loop domains that have highly conserved boundary CTCF sites and show a notable enrichment of individual developmental regulators. Importantly, perturbation of such a boundary in hPSCs interfered with proper differentiation through deregulated distal enhancer-promoter activity. Finally, we found that germline variations affecting such boundaries are subject to purifying selection and are underrepresented in the human population. Taken together, our findings highlight the importance of developmental gene isolation through chromosomal folding structures as a mechanism to ensure their proper expression.


Assuntos
Diferenciação Celular/genética , Perfilação da Expressão Gênica/métodos , Genoma Humano/genética , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Elementos Reguladores de Transcrição/genética , Sítios de Ligação/genética , Western Blotting , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , Elementos Facilitadores Genéticos/genética , Células-Tronco Embrionárias Humanas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA/métodos
11.
Int J Mol Sci ; 22(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34281244

RESUMO

Olfaction is an important neural system for survival and fundamental behaviors such as predator avoidance, food finding, memory formation, reproduction, and social communication. However, the neural circuits and pathways associated with the olfactory system in various behaviors are not fully understood. Recent advances in optogenetics, high-resolution in vivo imaging, and reconstructions of neuronal circuits have created new opportunities to understand such neural circuits. Here, we generated a transgenic zebrafish to manipulate olfactory signal optically, expressing the Channelrhodopsin (ChR2) under the control of the olfactory specific promoter, omp. We observed light-induced neuronal activity of olfactory system in the transgenic fish by examining c-fos expression, and a calcium indicator suggesting that blue light stimulation caused activation of olfactory neurons in a non-invasive manner. To examine whether the photo-activation of olfactory sensory neurons affect behavior of zebrafish larvae, we devised a behavioral choice paradigm and tested how zebrafish larvae choose between two conflicting sensory cues, an aversive odor or the naturally preferred phototaxis. We found that when the conflicting cues (the preferred light and aversive odor) were presented together simultaneously, zebrafish larvae swam away from the aversive odor. However, the transgenic fish with photo-activation were insensitive to the aversive odor and exhibited olfactory desensitization upon optical stimulation of ChR2. These results show that an aversive olfactory stimulus can override phototaxis, and that olfaction is important in decision making in zebrafish. This new transgenic model will be useful for the analysis of olfaction related behaviors and for the dissection of underlying neural circuits.


Assuntos
Channelrhodopsins/metabolismo , Percepção Olfatória/genética , Olfato/genética , Animais , Animais Geneticamente Modificados/genética , Channelrhodopsins/genética , Sinais (Psicologia) , Larva/fisiologia , Luz , Rede Nervosa/metabolismo , Neurônios/metabolismo , Odorantes , Optogenética/métodos , Estimulação Luminosa , Regiões Promotoras Genéticas/genética , Natação , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
12.
Int J Mol Sci ; 22(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34298865

RESUMO

Poplar is one of the most important tree species in the north temperate zone, but poplar plantations are quite water intensive. We report here that CaMV 35S promoter-driven overexpression of the PdERECTA gene, which is a member of the LRR-RLKs family from Populus nigra × (Populus deltoides × Populus nigra), improves water use efficiency and enhances drought tolerance in triploid white poplar. PdERECTA localizes to the plasma membrane. Overexpression plants showed lower stomatal density and larger stomatal size. The abaxial stomatal density was 24-34% lower and the stomatal size was 12-14% larger in overexpression lines. Reduced stomatal density led to a sharp restriction of transpiration, which was about 18-35% lower than the control line, and instantaneous water use efficiency was around 14-63% higher in overexpression lines under different conditions. These phenotypic changes led to increased drought tolerance. PdERECTA overexpression plants not only survived longer after stopping watering but also performed better when supplied with limited water, as they had better physical and photosynthesis conditions, faster growth rate, and higher biomass accumulation. Taken together, our data suggest that PdERECTA can alter the development pattern of stomata to reduce stomatal density, which then restricts water consumption, conferring enhanced drought tolerance to poplar. This makes PdERECTA trees promising candidates for establishing more water use efficient plantations.


Assuntos
Proteínas de Plantas/genética , Estômatos de Plantas/genética , Populus/genética , Água/metabolismo , Biomassa , Membrana Celular/genética , Membrana Celular/metabolismo , Secas , Regulação da Expressão Gênica de Plantas/genética , Fotossíntese/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Estômatos de Plantas/metabolismo , Transpiração Vegetal/genética , Populus/metabolismo , Regiões Promotoras Genéticas/genética
13.
Plant Sci ; 310: 110951, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34315581

RESUMO

Plants have evolved different mechanisms to increase their tolerance to aluminum (Al) toxicity and low pH in the soil. The Zn finger transcription factor SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) plays an essential role in the adaptation of plants to Al and low pH stresses. In this work, we isolated the ScSTOP1 gene from rye (Secale cereale L.), which is located on chromosome 3RS. The ectopic expression of ScSTOP1 complements the Arabidopsis stop1 mutation in terms of root growth inhibition due to Al and pH stress, as well as phosphate starvation tolerance, suggesting that rye ScSTOP1 is a functional ortholog of AtSTOP1. A putative STOP1 binding motif was identified in the promoter of a well-known STOP1 target from rye and Arabidopsis and was later corroborated by genomic DAP-seq analyses. Coexpression analyses verified that ScSTOP1 activated the promoter of ScALMT1. We have also identified a putative phosphorylatable serine in STOP1 that is phylogenetically conserved and critical for such activation. Our data indicated that ScSTOP1 also regulated Al and pH tolerance in rye.


Assuntos
Alumínio/toxicidade , Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Secale/metabolismo , Proteínas de Arabidopsis/genética , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Concentração de Íons de Hidrogênio , Mutação/genética , Transportadores de Ânions Orgânicos/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Secale/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Nat Commun ; 12(1): 4560, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315876

RESUMO

Alcoholic hepatitis (AH) is associated with liver neutrophil infiltration through activated cytokine pathways leading to elevated chemokine expression. Super-enhancers are expansive regulatory elements driving augmented gene expression. Here, we explore the mechanistic role of super-enhancers linking cytokine TNFα with chemokine amplification in AH. RNA-seq and histone modification ChIP-seq of human liver explants show upregulation of multiple CXCL chemokines in AH. Liver sinusoidal endothelial cells (LSEC) are identified as an important source of CXCL expression in human liver, regulated by TNFα/NF-κB signaling. A super-enhancer is identified for multiple CXCL genes by multiple approaches. dCas9-KRAB-mediated epigenome editing or pharmacologic inhibition of Bromodomain and Extraterminal (BET) proteins, transcriptional regulators vital to super-enhancer function, decreases chemokine expression in vitro and decreases neutrophil infiltration in murine models of AH. Our findings highlight the role of super-enhancer in propagating inflammatory signaling by inducing chemokine expression and the therapeutic potential of BET inhibition in AH treatment.


Assuntos
Quimiocinas/biossíntese , Citocinas/farmacologia , Elementos Facilitadores Genéticos , Hepatite Alcoólica/genética , Animais , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Regiões Promotoras Genéticas/genética , RNA-Seq , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Anticancer Res ; 41(7): 3309-3315, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230126

RESUMO

BACKGROUND/AIM: Matrix metalloproteinase 9 (MMP9) is highly expressed in gastric cancer but the role of MMP9 is unclear. This study aimed at revealing the association of MMP9 promoter rs3918242 genotypes with gastric cancer risk. MATERIALS AND METHODS: MMP9 rs3918242 genotypes of 121 patients with gastric cancer and 363 healthy individuals were examined by polymerase chain reaction-restriction fragment length polymorphism methodology using serum samples. RESULTS: MMP9 rs3918242 TT genotype carriers had an elevated gastric cancer risk compared to wild-type CC carriers (odds ratio=3.92, 95% confidence interval=1.28-11.99; p=0.0103). Patients with CT/TT genotypes were at higher risk of metastasis (p=0.0178) than those with CC. No correlation was found between MMP9 rs3918242 genotype and gastric cancer risk with smoking or alcohol behavior, nor Helicobacter pylori infection. No correlation was observed for MMP9 rs3918242 genotypic distributions with age, gender, or body mass index. CONCLUSION: Carrying a T allele for MMP9 rs3918242 may be predictive for higher gastric cancer risk, and as a predictor for higher risk of metastasis.


Assuntos
Predisposição Genética para Doença/genética , Metaloproteinase 9 da Matriz/genética , Regiões Promotoras Genéticas/genética , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Feminino , Genótipo , Infecções por Helicobacter/genética , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição/genética , Fatores de Risco
16.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199464

RESUMO

The influence of salt stress on gene expression, promoter methylation, and enzymatic activity of the mitochondrial and cytosolic forms of aconitase and fumarase has been investigated in maize (Zea mays L.) seedlings. The incubation of maize seedlings in 150-mM NaCl solution resulted in a several-fold increase of the mitochondrial activities of aconitase and fumarase that peaked at 6 h of NaCl treatment, while the cytosolic activity of aconitase and fumarase decreased. This corresponded to the decrease in promoter methylation of the genes Aco1 and Fum1 encoding the mitochondrial forms of these enzymes and the increase in promoter methylation of the genes Aco2 and Fum2 encoding the cytosolic forms. The pattern of expression of the genes encoding the mitochondrial forms of aconitase and fumarase corresponded to the profile of the increase of the stress marker gene ZmCOI6.1. It is concluded that the mitochondrial and cytosolic forms of aconitase and fumarase are regulated via the epigenetic mechanism of promoter methylation of their genes in the opposite ways in response to salt stress. The role of the mitochondrial isoforms of aconitase and fumarase in the elevation of respiration under salt stress is discussed.


Assuntos
Aconitato Hidratase/genética , Metilação de DNA/genética , Fumarato Hidratase/genética , Estresse Salino/genética , Citosol/enzimologia , Regulação da Expressão Gênica de Plantas/genética , Mitocôndrias/enzimologia , Regiões Promotoras Genéticas/genética , Zea mays/genética , Zea mays/crescimento & desenvolvimento
17.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199659

RESUMO

Herein we describe a combined experimental and in silico study of the interaction of a series of pyrazolo[1,2-a]benzo[1,2,3,4]tetrazin-3-one derivatives (PBTs) with parallel G-quadruplex (GQ) DNA aimed at correlating their previously reported anticancer activities and the stabilizing effects observed by us on c-myc oncogene promoter GQ structure. Circular dichroism (CD) melting experiments were performed to characterize the effect of the studied PBTs on the GQ thermal stability. CD measurements indicate that two out of the eight compounds under investigation induced a slight stabilizing effect (2-4 °C) on GQ depending on the nature and position of the substituents. Molecular docking results allowed us to verify the modes of interaction of the ligands with the GQ and estimate the binding affinities. The highest binding affinity was observed for ligands with the experimental melting temperatures (Tms). However, both stabilizing and destabilizing ligands showed similar scores, whilst Molecular Dynamics (MD) simulations, performed across a wide range of temperatures on the GQ in water solution, either unliganded or complexed with two model PBT ligands with the opposite effect on the Tms, consistently confirmed their stabilizing or destabilizing ability ascertained by CD. Clues about a relation between the reported anticancer activity of some PBTs and their ability to stabilize the GQ structure of c-myc emerged from our study. Furthermore, Molecular Dynamics simulations at high temperatures are herein proposed for the first time as a means to verify the stabilizing or destabilizing effect of ligands on the GQ, also disclosing predictive potential in GQ-targeting drug discovery.


Assuntos
DNA/efeitos dos fármacos , Quadruplex G/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/química , Telômero/química , Sítios de Ligação/efeitos dos fármacos , Dicroísmo Circular , Simulação por Computador , DNA/química , DNA/ultraestrutura , Humanos , Ligantes , Simulação de Dinâmica Molecular , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-myc/ultraestrutura , Telômero/efeitos dos fármacos , Telômero/genética
18.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203933

RESUMO

Natural resistance-associated macrophage proteins (Nramps) are specific metal transporters in plants with different functions among various species. The evolutionary and functional information of the Nramp gene family in Spirodela polyrhiza has not been previously reported in detail. To identify the Nramp genes in S. polyrhiza, we performed genome-wide identification, characterization, classification, and cis-elements analysis among 22 species with 138 amino acid sequences. We also conducted chromosomal localization and analyzed the synteny relationship, promoter, subcellular localization, and expression patterns in S. polyrhiza. ß-Glucuronidase staining indicated that SpNramp1 and SpNramp3 mainly accumulated in the root and joint between mother and daughter frond. Moreover, SpNramp1 was also widely displayed in the frond. SpNramp2 was intensively distributed in the root and frond. Quantitative real-time PCR results proved that the SpNramp gene expression level was influenced by Cd stress, especially in response to Fe or Mn deficiency. The study provides detailed information on the SpNramp gene family and their distribution and expression, laying a beneficial foundation for functional research.


Assuntos
Araceae/genética , Cádmio/toxicidade , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Araceae/efeitos dos fármacos , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/metabolismo , Cromossomos de Plantas/genética , Sequência Conservada , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/efeitos dos fármacos , Sintenia/genética
19.
Int J Mol Sci ; 22(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204945

RESUMO

A lesser known but crucially important downstream effect of Rho family GTPases is the regulation of gene expression. This major role is mediated via the cytoskeleton, the organization of which dictates the nucleocytoplasmic shuttling of a set of transcription factors. Central among these is myocardin-related transcription factor (MRTF), which upon actin polymerization translocates to the nucleus and binds to its cognate partner, serum response factor (SRF). The MRTF/SRF complex then drives a large cohort of genes involved in cytoskeleton remodeling, contractility, extracellular matrix organization and many other processes. Accordingly, MRTF, activated by a variety of mechanical and chemical stimuli, affects a plethora of functions with physiological and pathological relevance. These include cell motility, development, metabolism and thus metastasis formation, inflammatory responses and-predominantly-organ fibrosis. The aim of this review is twofold: to provide an up-to-date summary about the basic biology and regulation of this versatile transcriptional coactivator; and to highlight its principal involvement in the pathobiology of kidney disease. Acting through both direct transcriptional and epigenetic mechanisms, MRTF plays a key (yet not fully appreciated) role in the induction of a profibrotic epithelial phenotype (PEP) as well as in fibroblast-myofibroblast transition, prime pathomechanisms in chronic kidney disease and renal fibrosis.


Assuntos
Nefropatias/genética , Complexos Multiproteicos/genética , Fator de Resposta Sérica/genética , Transativadores/genética , Movimento Celular/genética , Núcleo Celular/genética , Citoesqueleto/genética , Regulação da Expressão Gênica/genética , Humanos , Nefropatias/patologia , Regiões Promotoras Genéticas/genética
20.
Nat Commun ; 12(1): 4503, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301927

RESUMO

Promoter-proximal pausing of RNA polymerase II is a key process regulating gene expression. In latent HIV-1 cells, it prevents viral transcription and is essential for latency maintenance, while in acutely infected cells the viral factor Tat releases paused polymerase to induce viral expression. Pausing is fundamental for HIV-1, but how it contributes to bursting and stochastic viral reactivation is unclear. Here, we performed single molecule imaging of HIV-1 transcription. We developed a quantitative analysis method that manages multiple time scales from seconds to days and that rapidly fits many models of promoter dynamics. We found that RNA polymerases enter a long-lived pause at latent HIV-1 promoters (>20 minutes), thereby effectively limiting viral transcription. Surprisingly and in contrast to current models, pausing appears stochastic and not obligatory, with only a small fraction of the polymerases undergoing long-lived pausing in absence of Tat. One consequence of stochastic pausing is that HIV-1 transcription occurs in bursts in latent cells, thereby facilitating latency exit and providing a rationale for the stochasticity of viral rebounds.


Assuntos
Regulação Viral da Expressão Gênica , Infecções por HIV/genética , HIV-1/genética , Regiões Promotoras Genéticas/genética , Latência Viral/genética , Algoritmos , RNA Polimerases Dirigidas por DNA/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/fisiologia , Células HeLa , Humanos , Modelos Genéticos , Processos Estocásticos , Fatores de Tempo , Ativação Viral/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
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