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1.
An Acad Bras Cienc ; 91(3): e20180646, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411259

RESUMO

The hepatoprotective effects of the ethanolic extracts of propolis (EEP) on alcohol-induced liver steatosis were investigated in Wistar rats. Chronic alcoholic fatty liver was induced by administration of 52% alcohol to male Wistar rats at the dose of 1% body weight for 7 weeks. Then animals were simultaneously treated with 50% ethanol solutions of EEP or normal saline at the dose of 0.1% body weight for 4 further weeks. Serological analyses and liver histopathology studies were performed to investigate the development of steatosis. Microarray analysis was conducted to investigate the alterations of hepatic gene expression profiling. Our results showed that 4-week treatment of EEP helped to restore the levels of various blood indices, liver function enzymes and the histopathology of liver tissue to normal levels. Results from the microarray analysis revealed that the hepatic expressions of genes involved in lipogenesis were significantly down-regulated by EEP treatment, while the transcriptional expressions of functional genes participating in fatty acids oxidation were markedly increased. The ability of EEP to reduce the negative effects of alcohol on liver makes propolis a potential natural product for the alternative treatment of alcoholic fatty liver.


Assuntos
Fígado Gorduroso Alcoólico/metabolismo , Hepatopatias Alcoólicas/metabolismo , Extratos Vegetais/metabolismo , Própole/metabolismo , Substâncias Protetoras/metabolismo , Alanina Transaminase/metabolismo , Animais , Apiterapia/métodos , Aspartato Aminotransferases/metabolismo , Colesterol/metabolismo , Modelos Animais de Doenças , Etanol , Ácidos Graxos/biossíntese , Fígado Gorduroso Alcoólico/tratamento farmacológico , Fígado Gorduroso Alcoólico/genética , Fígado Gorduroso Alcoólico/patologia , Hepatopatias Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/patologia , Masculino , Oxirredução , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Própole/química , Própole/uso terapêutico , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Ratos Wistar , Análise Serial de Tecidos/métodos , Transcrição Genética/genética , Triglicerídeos/metabolismo
2.
Pestic Biochem Physiol ; 158: 54-60, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378361

RESUMO

Extensive planting of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has spurred increasingly rapid evolution of resistance in pests. In the pink bollworm, Pectinophora gossypiella, a devastating global pest, resistance to Bt toxin Cry1Ac produced by transgenic cotton is linked with mutations in a gene (PgCad1) encoding a cadherin protein that binds Cry1Ac in the larval midgut. We previously reported a long non-coding RNA (lncRNA) in intron 20 of cadherin alleles associated with both resistance and susceptibility to Cry1Ac. Here we tested the hypothesis that reducing expression of this lncRNA decreases transcription of PgCad1 and susceptibility to Cry1Ac. Quantitative RT-PCR showed that feeding susceptible neonates small interfering RNAs (siRNAs) targeting this lncRNA but not PgCad1 decreased the abundance of transcripts of both the lncRNA and PgCad1. Moreover, neonates fed the siRNAs had lower susceptibility to Cry1Ac. The results imply that the lncRNA increases transcription of PgCad1 and susceptibility of pink bollworm to Cry1Ac. The results suggest that disruption of lncRNA expression could be a novel mechanism of pest resistance to Bt toxins.


Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/farmacologia , Caderinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Mariposas/efeitos dos fármacos , RNA Longo não Codificante/genética , Transcrição Genética/genética , Animais , Bacillus thuringiensis/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mariposas/genética , Mariposas/metabolismo , Controle Biológico de Vetores
3.
Nature ; 571(7765): 419-423, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292545

RESUMO

Single-cell RNA sequencing (scRNA-seq) has highlighted the important role of intercellular heterogeneity in phenotype variability in both health and disease1. However, current scRNA-seq approaches provide only a snapshot of gene expression and convey little information on the true temporal dynamics and stochastic nature of transcription. A further key limitation of scRNA-seq analysis is that the RNA profile of each individual cell can be analysed only once. Here we introduce single-cell, thiol-(SH)-linked alkylation of RNA for metabolic labelling sequencing (scSLAM-seq), which integrates metabolic RNA labelling2, biochemical nucleoside conversion3 and scRNA-seq to record transcriptional activity directly by differentiating between new and old RNA for thousands of genes per single cell. We use scSLAM-seq to study the onset of infection with lytic cytomegalovirus in single mouse fibroblasts. The cell-cycle state and dose of infection deduced from old RNA enable dose-response analysis based on new RNA. scSLAM-seq thereby both visualizes and explains differences in transcriptional activity at the single-cell level. Furthermore, it depicts 'on-off' switches and transcriptional burst kinetics in host gene expression with extensive gene-specific differences that correlate with promoter-intrinsic features (TBP-TATA-box interactions and DNA methylation). Thus, gene-specific, and not cell-specific, features explain the heterogeneity in transcriptomes between individual cells and the transcriptional response to perturbations.


Assuntos
Regulação da Expressão Gênica/genética , Análise de Sequência de RNA/métodos , Análise de Célula Única , Transcrição Genética/genética , Alquilação , Animais , Ciclo Celular , Citomegalovirus/fisiologia , Metilação de DNA , Fibroblastos/metabolismo , Fibroblastos/virologia , Cinética , Camundongos , Regiões Promotoras Genéticas/genética , RNA/análise , RNA/química , Compostos de Sulfidrila/química
4.
Gene ; 714: 143985, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330236

RESUMO

In all eukaryotes, the response to heat stress (HS) is dependent on the activity of HS transcription factors (Hsfs). Plants contain a large number of Hsfs, however, only members of the HsfA1 subfamily are considered as master regulators of stress response and thermotolerance. In Solanum lycopersicum, among the four HsfA1 members, only HsfA1a has been proposed to possess a master regulator function. We performed a comparative analysis of HsfA1a, HsfA1b, HsfA1c and HsfA1e at different levels of regulation and function. HsfA1a is constitutively expressed under control and stress conditions, while the other members are induced in specific tissues and stages of HS response. Despite that all members are localized in the nucleus when expressed in protoplasts, only HsfA1a shows a wide range of basal activity on several HS-induced genes. In contrast, HsfA1b, HsfA1c, and HsfA1e show only high activity for specific subsets of genes. Domain swapping mutants between HsfA1a and HsfA1c revealed that the variation in that transcriptional transactivation activity is due to differences in the DNA binding domain (DBD). Specifically, we identified a conserved arginine (R107) residue in the turn of ß3 and ß4 sheet in the C-terminus of the DBD of HsfA1a that is highly conserved in plant HsfA1 proteins, but is replaced by leucine and cysteine in tomato HsfA1c and HsfA1e, respectively. Although not directly involved in DNA interaction, R107 contributes to DNA binding and consequently the activity of HsfA1a. Thus, we demonstrate that this variation in DBD in part explains the functional diversification of tomato HsfA1 members.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Choque Térmico/genética , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Temperatura Alta , Domínios Proteicos/genética , Protoplastos/fisiologia , Temperatura Ambiente , Termotolerância/genética , Transcrição Genética/genética , Ativação Transcricional/genética
5.
Mol Biol (Mosk) ; 53(3): 485-496, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31184614

RESUMO

Human apolipoprotein A-I (ApoA-I) is a major structural and functional protein component of high-density lipoprotein (HDL). ApoA-I constitutes ~75% of the protein content of HDL. The main sites of ApoA-I synthesis in humans are the liver and the small intestine. The mechanisms that govern tissue-specific apoA-I transcription in tissues and organs other than the liver and the small intestine are poorly understood. It is known that the human apoA-I has two additional promoters, the proximal and the distal one. In this work these two alternative apoA-I promoters are characterized, their transcription start sites are mapped and their competition for apoA-Itranscription is demonstrated; the role of the alternative promoters in apoA-I expression in human cells and tissues other than hepatocytes and enterocytes is discussed.


Assuntos
Apolipoproteína A-I/genética , Regiões Promotoras Genéticas/genética , Sítio de Iniciação de Transcrição , Transcrição Genética/genética , Humanos , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Fígado/citologia , Fígado/metabolismo , Especificidade de Órgãos/genética
6.
Vet Res ; 50(1): 42, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164173

RESUMO

Haemonchus contortus (H. contortus) has evolved sophisticated evasion mechanisms to ensure their survival, including generating excretion and secretion products (ESPs) to regulate the secretion of host cytokines. Interleukin 4 (IL4) is a classic T-helper cell type 2 (Th2)-type cytokine that plays an irreplaceable role against nematode infection. In this study, three proteins, glutathione S-transferase domain containing protein (HcGST), transthyretin domain containing protein (HcTTR) and calponin actin-binding domain containing protein (HcCab), were identified to bind to goat IL4 by co-immunoprecipitation (Co-IP) assays and yeast two-hybrid screening. Additionally, cell proliferation analysis showed that HcTTR blocked the IL4-induced proliferation of peripheral blood mononuclear cells in goats, while HcGST and HcCab did not. In addition, HcTTR could also downregulate the transcription of candidate genes in the IL4-induced JAK/STAT pathway. These results indicated that HcTTR is a novel antagonist against goat IL4 from HcESPs, and this information could improve our understanding of the relationship between host cytokines and parasite infections.


Assuntos
Regulação para Baixo/genética , Cabras/fisiologia , Haemonchus/genética , Proteínas de Helminto/genética , Interleucina-4/antagonistas & inibidores , Receptores de Albumina/genética , Animais , Cabras/parasitologia , Haemonchus/metabolismo , Proteínas de Helminto/metabolismo , Leucócitos Mononucleares/metabolismo , Receptores de Albumina/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais/genética , Transcrição Genética/genética
7.
Biochemistry (Mosc) ; 84(2): 137-146, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31216972

RESUMO

Telomeres are complex and dynamic structures whose functions and composition change during the cell cycle and development. Telomeric transcripts are essential components of telomeres. Transcription regulation and cellular levels of telomeric RNAs are closely associated with the control of telomere length, formation of telomeric chromatin, telomere replication, and regulation of non-telomeric gene transcription, which indicates a critical regulatory role of telomeric RNAs in telomere protection and transmission of signals about the state of telomeres to cellular genes. The studies of telomeric transcriptome in early Drosophila development have revealed a new level of genomic stability regulation involving telomeric RNAs. Due to their ability to interact with multiple proteins and to translocate in the cell, telomeric transcripts are important participants of telomeric signaling pathways, whose mechanisms are still to be understood at the organism level.


Assuntos
Telômero/genética , Transcrição Genética/genética , Animais , Humanos
8.
Cancer Sci ; 110(8): 2368-2377, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31222863

RESUMO

Macrophages are essential inflammatory cells which regulate the features of immune reactions within tumors. Many studies have reported their regulatory roles in immunity through cytokines and cell signaling. However, relatively few studies have focused on their metabolic features and mechanisms. We aimed to determine the signaling pathway regulating cell metabolism and the mechanism related to the regulation of human tumor-associated macrophages (TAMs) in gastric cancer (GC). Tumor-infiltrated macrophages were isolated from human GC tissues using magnetic beads, gene transcription was determined by real-time PCR, protein expression was monitored using western blots, metabolites were determined using HPLC, and transcriptional regulation was analyzed by the luciferase-based reporter gene system. A significant decrease in microRNA (miR)-30c and an increase in regulated in development and DNA damage responses 1 (REDD1) were detected in human GC TAMs, the transcription of miR-30c was negatively correlated with REDD1. MicroRNA-30c expression was suppressed by hypoxia-inducible factor-1α activation and related to decreased mTOR activity as well as glycolysis in human GC TAMs. Hypoxia-regulated miR-30c downregulated REDD-1 expression by targeting its 3'UTR. Overexpression of miR-30c or restored mTOR activity in macrophages with miR-30cLow expression promoted M1 macrophage differentiation and function in TAMs. Therefore, hypoxia in the human GC microenvironment suppressed the expression of miR-30c, and decreased mTOR activity as well as glycolysis in GC TAMs, thus inhibiting M1 differentiation and function. These results provide a novel metabolic strategy for tumor microenvironment-based therapy.


Assuntos
Glicólise/genética , Hipóxia/genética , Macrófagos/patologia , MicroRNAs/genética , Neoplasias Gástricas/genética , Serina-Treonina Quinases TOR/genética , Regiões 3' não Traduzidas/genética , Diferenciação Celular , Linhagem Celular , Proliferação de Células/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/genética , Neoplasias Gástricas/patologia , Fatores de Transcrição/genética , Transcrição Genética/genética , Microambiente Tumoral/genética
9.
Cancer Sci ; 110(8): 2328-2336, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31228211

RESUMO

Changes of nuclear localization of lineage-specific genes from a transcriptionally inert to permissive environment are a crucial step in establishing the identity of a cell. Noncoding RNA transcription-mediated genome folding and activation of target gene expression have been found in a variety of cell types. Noncoding RNA ThymoD (thymocyte differentiation factor) transcription at superenhancers is essential for mouse T-cell lineage commitment. The cessation of ThymoD transcription abolishes transcription-mediated demethylation, recruiting looping factors such as the cohesin complex, CCCTC-binding factor (CTCF), ultimately leading to the phenotype of severe combined immunodeficiency and T-cell leukemia/lymphoma. In this review, we describe the functional role of RNA polymerase II-mediated transcription at enhancers and in genome folding. We also highlight the involvement of faulty activation or suppression of enhancer transcription and enhancer-promoter interaction in cancer development.


Assuntos
Elementos Facilitadores Genéticos/genética , Genoma/genética , Neoplasias/genética , RNA não Traduzido/genética , Transcrição Genética/genética , Animais , Humanos , Regiões Promotoras Genéticas/genética
10.
Nat Commun ; 10(1): 2633, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201330

RESUMO

Long-range chromatin interactions are important for transcriptional regulation of genes, many of which are related to complex agronomics traits. However, the pattern of three-dimensional chromatin interactions remains unclear in plants. Here we report the generation of chromatin interaction analysis by paired-end tag sequencing (ChIA-PET) data and the construction of extensive H3K4me3- and H3K27ac-centered chromatin interaction maps in maize. Results show that the interacting patterns between proximal and distal regulatory regions of genes are highly complex and dynamic. Genes with chromatin interactions have higher expression levels than those without interactions. Genes with proximal-proximal interactions prefer to be transcriptionally coordinated. Tissue-specific proximal-distal interactions are associated with tissue-specific expression of genes. Interactions between proximal and distal regulatory regions further interweave into organized network communities that are enriched in specific biological functions. The high-resolution chromatin interaction maps will help to understand the transcription regulation of genes associated with complex agronomic traits of maize.


Assuntos
Cromatina/metabolismo , Regulação da Expressão Gênica de Plantas , Sequências Reguladoras de Ácido Nucleico/genética , Transcrição Genética/genética , Zea mays/genética , Cromatina/genética , Imunoprecipitação da Cromatina , Mapeamento Cromossômico , Produção Agrícola , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Histonas/genética , Histonas/imunologia , Regiões Promotoras Genéticas , Locos de Características Quantitativas/genética
11.
Artif Cells Nanomed Biotechnol ; 47(1): 1782-1787, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31062612

RESUMO

Hepatic steatosis is one of the most important features of the pathogenesis for non-alcoholic fatty liver disease. Fat deposition in liver cells can influence hepatic lipogenesis along with other metabolic pathways and further lead to the irreversible liver cirrhosis and injury. However, the underlying mechanism of steatosis remains largely unexplored. Our previous study revealed that AQP7 played an important role in liver steatosis. In this study, we determined that the transcriptional level of AQP7 was up-regulated by estrogen receptor alpha (ERα) upon 17ß-estradiol (E2) and oleic acids treated HepG2 cells. Furthermore, we identified long non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) as a potential hallmark which was down-regulated in ERα silencing HepG2 cells by RNA-Seq. Finally, we validated that the 3' terminal nucleotides of NEAT1 were contributed for the interaction with ERα to facilitate AQP7 transcription to suppress liver steatosis. Overall, our study gave evidence that NEAT1 played an important role in the activation of ERα to regulate AQP7-mediated hepatic steatosis.


Assuntos
Aquaporinas/genética , Receptor alfa de Estrogênio/metabolismo , Fígado Gorduroso/genética , Regulação da Expressão Gênica/genética , RNA Longo não Codificante/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Hep G2 , Humanos , RNA Longo não Codificante/metabolismo , Transcrição Genética/genética
12.
Transcription ; 10(3): 164-170, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31057041

RESUMO

In eukaryotes, divergent transcription is a major source of noncoding RNAs. Recent studies have uncovered that in yeast, the transcription factor Rap1 restricts transcription in the divergent direction and thereby controls promoter directionality. Here, we summarize these findings, propose regulatory principles, and discuss the implications for eukaryotic gene regulation.


Assuntos
Regiões Promotoras Genéticas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Ligação a Telômeros/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética/genética , Saccharomyces cerevisiae/metabolismo
13.
World J Gastroenterol ; 25(15): 1797-1816, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31057295

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC. Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network. Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein (YAP) and WW-domain-containing transcriptional co-activator with PDZ-binding motif (TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pancreáticas/genética , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Reposicionamento de Medicamentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Metformina/farmacologia , Metformina/uso terapêutico , Terapia de Alvo Molecular/métodos , Mutação , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Fosfoproteínas/antagonistas & inibidores , Prognóstico , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética
14.
Pol J Microbiol ; 68(1): 43-50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050252

RESUMO

Several biotypes of the Gram-negative bacterium Serratia marcescens produce the tri-pyrole pigment and secondary metabolite prodigiosin. The biological activities of this pigment have therapeutic potential. For over half a century it has been known that biosynthesis of prodi giosin is inhibited when bacteria are grown at elevated temperatures, yet the fundamental mechanism underlying this thermoregulation has not been characterized. In this study, chromosomal and plasmid-borne luxCDABE transcriptional reporters revealed reduced transcription of the prodigiosin biosynthetic operon at 37°C compared to 30°C indicating transcriptional control of pigment production. Moreover, induced expression of the prodigiosin biosynthetic operon at 37°C was able to produce pigmented colonies and cultures demonstrating that physiological conditions at 37°C allow prodigiosin production and indicating that post-transcriptional control is not a major contributor to the thermoregulation of prodigiosin pigmentation. Genetic experiments support the model that the HexS transcription factor is a key contributor to thermoregulation of pigmentation, whereas CRP plays a minor role, and a clear role for EepR and PigP was not observed. Together, these data indicate that thermoregulation of prodigiosin production at elevated temperatures is controlled largely, if not exclusively, at the transcriptional level.Several biotypes of the Gram-negative bacterium Serratia marcescens produce the tri-pyrole pigment and secondary metabolite prodigiosin. The biological activities of this pigment have therapeutic potential. For over half a century it has been known that biosynthesis of prodi giosin is inhibited when bacteria are grown at elevated temperatures, yet the fundamental mechanism underlying this thermoregulation has not been characterized. In this study, chromosomal and plasmid-borne luxCDABE transcriptional reporters revealed reduced transcription of the prodigiosin biosynthetic operon at 37°C compared to 30°C indicating transcriptional control of pigment production. Moreover, induced expression of the prodigiosin biosynthetic operon at 37°C was able to produce pigmented colonies and cultures demonstrating that physiological conditions at 37°C allow prodigiosin production and indicating that post-transcriptional control is not a major contributor to the thermoregulation of prodigiosin pigmentation. Genetic experiments support the model that the HexS transcription factor is a key contributor to thermoregulation of pigmentation, whereas CRP plays a minor role, and a clear role for EepR and PigP was not observed. Together, these data indicate that thermoregulation of prodigiosin production at elevated temperatures is controlled largely, if not exclusively, at the transcriptional level.


Assuntos
Regulação Bacteriana da Expressão Gênica/genética , Prodigiosina/biossíntese , Serratia marcescens/genética , Serratia marcescens/metabolismo , Fatores de Transcrição/genética , Transcrição Genética/genética , Aciltransferases/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Temperatura Alta , Oxirredutases/genética , Ativação Transcricional/genética
15.
Cancer Sci ; 110(8): 2676-2683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069877

RESUMO

Well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) are the most common types of liposarcoma. Although WDLPS and DDLPS patients receive intensive treatment including radical surgery and systemic therapy, their overall 5-year survival rates are 90% and 30%, respectively, indicating that DDLPS is clinically more aggressive. We examined whether adipogenic stimulation induces adipogenesis in human WDLPS/DDLPS cells by using dexamethasone, indomethacin, insulin, and 3-isobutyl-1-methylxanthine (IBMX), all putative medications or drugs. Functional in vitro experiments showed that treatment with these four compounds induced adipogenic potency by transcriptional and translational upregulation of genes related to the maintenance of stemness and adipogenic differentiation. Using in vivo xenograft models, we found that the induction of stemness and adipogenesis inhibited the tumorigenic potency of DDLPS. This study suggests a potential application of drug repositioning in which adipogenesis-inducing compounds could be used to treat DDLPS patients in a clinical setting.


Assuntos
Adipogenia/genética , Desdiferenciação Celular/genética , Proliferação de Células/genética , Lipossarcoma/genética , 1-Metil-3-Isobutilxantina/farmacologia , Adipogenia/efeitos dos fármacos , Desdiferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Dexametasona/farmacologia , Humanos , Indometacina/farmacologia , Insulina/farmacologia , Lipossarcoma/tratamento farmacológico , Lipossarcoma/patologia , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
16.
Anal Chim Acta ; 1067: 107-114, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31047141

RESUMO

A novel and versatile immunosensing strategy was developed for ultrasensitive and specific detection of proteins by organically integrating interfacial specific target recognition and homogeneous transcription amplification. In principle, classic antigen-antibody sandwich structure on the microplate could realize the specific identification of target protein. Biotinylated DNA probe was subsequently introduced by streptavidin-biotin system as a bridge linking interfacial and homogeneous reaction. The biotinylated DNA initiated exponential transcription amplification in the solution, which converted per target recognition event on the interface to numerous single-stranded RNA products in solution for highly sensitive fluorescence immunosensing. The proposed immunoassay based on interfacial recognition-induced homogeneous exponential transcription (IR-HET) for vascular endothelial growth factor (VEGF) detection showed a good linear range from 0.01 to 1000 pg/mL and the limit of detection as low as 1 fg/mL, which was 3 orders lower than traditional ELISA method. The established strategy was also successfully applied to directly detect VEGF from culture supernatants of tumor cells and clinical body fluid samples, proving very high sensitivity, selectivity and low matrix effect. Therefore, IR-HET-based immunosensing strategy might become a potential powerful tool be applied in ultrasensitive detection of low abundance protein biomarker for clinical early diagnosis, treatment and prognosis.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Líquidos Corporais/química , Imunoensaio , Transcrição Genética/genética , Fatores de Crescimento do Endotélio Vascular/análise , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Humanos , Técnicas de Amplificação de Ácido Nucleico , Fatores de Crescimento do Endotélio Vascular/genética
17.
Nat Commun ; 10(1): 2119, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31073172

RESUMO

Master transcription factors have the ability to direct and reverse cellular identities, and consequently their genes must be subject to particular transcriptional control. However, it is unclear which molecular processes are responsible for impeding their activation and safeguarding cellular identities. Here we show that the targeting of dCas9-VP64 to the promoter of the master transcription factor Sox1 results in strong transcript and protein up-regulation in neural progenitor cells (NPCs). This gene activation restores lost neuronal differentiation potential, which substantiates the role of Sox1 as a master transcription factor. However, despite efficient transactivator binding, major proportions of progenitor cells are unresponsive to the transactivating stimulus. By combining the transactivation domain with epigenome editing we find that among a series of euchromatic processes, the removal of DNA methylation (by dCas9-Tet1) has the highest potential to increase the proportion of cells activating foreign master transcription factors and thus breaking down cell identity barriers.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Epigênese Genética , Células-Tronco Neurais/fisiologia , Fatores de Transcrição SOXB1/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Metilação de DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Edição de Genes/métodos , Regulação da Expressão Gênica , Camundongos , Neuroglia/citologia , Neuroglia/fisiologia , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Guia/genética , RNA Guia/metabolismo , Fatores de Transcrição SOXB1/genética , Transcrição Genética/genética
18.
Cell Prolif ; 52(4): e12626, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31033072

RESUMO

In mammals, methylation of the 5th position of cytosine (5mC) seems to be a major epigenetic modification of DNA. This process can be reversed (resulting in cytosine) with high efficiency by dioxygenases of the ten-eleven translocation (TET) family, which perform oxidation of 5mC to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine and 5-carboxylcytosine. It has been demonstrated that these 5mC oxidation derivatives are in a dynamic state and have pivotal regulatory functions. Here, we comprehensively summarized the recent research progress in the understanding of the physiological functions of the TET proteins and their mechanisms of regulation of DNA methylation and transcription. Among the three TET genes, TET1 and TET2 expression levels have frequently been shown to be low in hepatocellular carcinoma (HCC) tissues and received most attention. The modulation of TET1 also correlates with microRNAs in a post-transcriptional regulatory process. Additionally, recent studies revealed that global genomic 5hmC levels are down-regulated in HCC tissues and cell lines. Combined with the reported results, identification of 5hmC signatures in HCC tissues and in circulating cell-free DNA will certainly contribute to early detection and should help to design therapeutic strategies against HCC. 5hmC might also be a novel prognostic biomarker of HCC. Thus, a detailed understanding of the molecular mechanisms resulting in the premalignant and aggressive transformation of TET proteins and cells with 5hmC disruption might help to develop novel epigenetic therapies for HCC.


Assuntos
5-Metilcitosina/análogos & derivados , Carcinoma Hepatocelular/genética , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , 5-Metilcitosina/metabolismo , Animais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/metabolismo , Citosina/análogos & derivados , Citosina/metabolismo , Metilação de DNA/genética , Dioxigenases/genética , Regulação para Baixo/genética , Epigênese Genética/genética , Humanos , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , Processamento Pós-Transcricional do RNA/genética , Transcrição Genética/genética
19.
Cell Prolif ; 52(4): e12617, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31012173

RESUMO

OBJECTIVES: The roles and related mechanisms of six2 in regulating non-small cell lung cancer (NSCLC) cells progression are unclear. This work aimed to explore the roles of six2 in NSCLC cell stemness. MATERIALS AND METHODS: Kaplan-Meier plotter analysis was used to examine the correlation between six2 expression and the survival of NSCLC patients. Quantitative reverse transcription PCR and Western blot were performed to detect six2 expression in clinical samples. Moreover, transwell migration, tumour spheroid formation and in vivo tumour formation assays were used to examine the effects of six2 on NSCLC cell progression. Additionally, methylation analysis was carried out to measure E-cadherin methylation level in different cells. Finally, cell viability assay was performed to explore the effects of six2 on chemotherapeutic sensitivity of NSCLC cells. RESULTS: Lung cancer patients with a higher six2 expression level displayed a shorter overall survival. Six2 expression was higher in lung cancer tissues than in normal adjacent tissues. Additionally, six2 knockdown suppressed NSCLC cell stemness. Mechanistically, six2 overexpression inhibited epithelial marker E-cadherin expression via stimulating its promoter methylation. And E-cadherin knockdown rescued six2 knockdown-induced decrease of NSCLC cancer cell stemness. Notably, six2 knockdown enhanced cisplatin sensitivity in parental NSCLC cells and attenuated cisplatin resistance in cisplatin-resistant NSCLC cells. CONCLUSIONS: Our results suggest that six2 facilitates NSCLC cell stemness and attenuates chemotherapeutic sensitivity via suppressing E-cadherin expression.


Assuntos
Antígenos CD/genética , Caderinas/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Epigênese Genética/genética , Proteínas de Homeodomínio/genética , Neoplasias Pulmonares/genética , Proteínas do Tecido Nervoso/genética , Transcrição Genética/genética , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cisplatino/farmacologia , Progressão da Doença , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Metilação/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Transcrição Genética/efeitos dos fármacos
20.
Nat Rev Cancer ; 19(5): 255-269, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962549

RESUMO

Recurrent chromosomal rearrangements leading to the generation of oncogenic fusion proteins are a common feature of many cancers. These aberrations are particularly prevalent in sarcomas and haematopoietic malignancies and frequently involve genes required for chromatin regulation and transcriptional control. In many cases, these fusion proteins are thought to be the primary driver of cancer development, altering chromatin dynamics to initiate oncogenic gene expression programmes. In recent years, mechanistic insights into the underlying molecular functions of a number of these oncogenic fusion proteins have been discovered. These insights have allowed the design of mechanistically anchored therapeutic approaches promising substantial treatment advances. In this Review, we discuss how our understanding of fusion protein function is informing therapeutic innovations and illuminating mechanisms of chromatin and transcriptional regulation in cancer and normal cells.


Assuntos
Cromatina/genética , Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Animais , Aberrações Cromossômicas , Expressão Gênica/genética , Humanos , Neoplasias/patologia , Transcrição Genética/genética
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