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1.
Cell ; 177(3): 722-736.e22, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-30955890

RESUMO

Insulin receptor (IR) signaling is central to normal metabolic control and dysregulated in prevalent chronic diseases. IR binds insulin at the cell surface and transduces rapid signaling via cytoplasmic kinases. However, mechanisms mediating long-term effects of insulin remain unclear. Here, we show that IR associates with RNA polymerase II in the nucleus, with striking enrichment at promoters genome-wide. The target genes were highly enriched for insulin-related functions including lipid metabolism and protein synthesis and diseases including diabetes, neurodegeneration, and cancer. IR chromatin binding was increased by insulin and impaired in an insulin-resistant disease model. Promoter binding by IR was mediated by coregulator host cell factor-1 (HCF-1) and transcription factors, revealing an HCF-1-dependent pathway for gene regulation by insulin. These results show that IR interacts with transcriptional machinery at promoters and identify a pathway regulating genes linked to insulin's effects in physiology and disease.


Assuntos
Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Receptor de Insulina/metabolismo , Animais , Linhagem Celular Tumoral , Cromatina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator C1 de Célula Hospedeira/antagonistas & inibidores , Fator C1 de Célula Hospedeira/genética , Fator C1 de Célula Hospedeira/metabolismo , Humanos , Insulina/metabolismo , Insulina/farmacologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Ligação Proteica , Subunidades Proteicas/metabolismo , Interferência de RNA , RNA Polimerase II/metabolismo , RNA Interferente Pequeno/metabolismo , Receptor de Insulina/química , Transdução de Sinais/efeitos dos fármacos
2.
Diabetologia ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404845

RESUMO

AIMS/HYPOTHESIS: p21 (CDC42/RAC1) activated kinase 1 (PAK1) is depleted in type 2 diabetic human islets compared with non-diabetic human islets, and acute PAK1 restoration in the islets can restore insulin secretory function ex vivo. We hypothesised that beta cell-specific PAK1 enrichment in vivo can mitigate high-fat-diet (HFD)-induced glucose intolerance by increasing the functional beta cell mass. METHODS: Human islets expressing exogenous PAK1 specifically in beta cells were used for bulk RNA-seq. Human EndoC-ßH1 cells overexpressing myc-tagged PAK1 were used for chromatin immunoprecipitation (ChIP) and ChIP-sequencing (ChIP-seq). Novel doxycycline-inducible beta cell-specific PAK1-expressing (ißPAK1-Tg) mice were fed a 45% HFD pre-induction for 3 weeks and for a further 3 weeks with or without doxycycline induction. These HFD-fed mice were evaluated for GTT, ITT, 6 h fasting plasma insulin and blood glucose, body composition, islet insulin content and apoptosis. RESULTS: Beta cell-specific PAK1 enrichment in type 2 diabetes human islets resulted in decreased beta cell apoptosis and increased insulin content. RNA-seq showed an upregulation of INS gene transcription by PAK1. Using clonal human beta cells, we found that PAK1 protein was localised in the cytoplasm and the nucleus. ChIP studies revealed that nuclear PAK1 enhanced pancreatic and duodenal homeobox1 (PDX1) and neuronal differentiation 1 (NEUROD1) binding to the INS promoter in a glucose-responsive manner. Importantly, the ißPAK1-Tg mice, when challenged with HFD and doxycycline induction displayed enhanced glucose tolerance, increased islet insulin content and reduced beta cell apoptosis when compared with ißPAK1-Tg mice without doxycycline induction. CONCLUSIONS/INTERPRETATION: PAK1 plays an unforeseen and beneficial role in beta cells by promoting insulin biogenesis via enhancing the expression of PDX1, NEUROD1 and INS, along with anti-apoptotic effects, that culminate in increased insulin content and beta cell mass in vivo and ameliorate diet-induced glucose intolerance. DATA AVAILABILITY: The raw and processed RNA-seq data and ChIP-seq data, which has been made publicly available at Gene Expression Omnibus (GEO) at https://www.ncbi.nlm.nih.gov/geo/ , can be accessed in GSE239382.

3.
Int J Mol Sci ; 25(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38473903

RESUMO

Autoimmune polyglandular syndromes (APS) are classified into four main categories, APS1-APS4. APS1 is caused by AIRE gene loss of function mutations, while the genetic background of the other APS remains to be clarified. Here, we investigated the potential association between AIRE gene promoter Single Nucleotide Polymorphisms (SNPs) and susceptibility to APS. We sequenced the AIRE gene promoter of 74 APS patients, also analyzing their clinical and autoantibody profile, and we further conducted molecular modeling studies on the identified SNPs. Overall, we found 6 SNPs (-230Y, -655R, -261M, -380S, -191M, -402S) of the AIRE promoter in patients' DNA. Interestingly, folding free energy calculations highlighted that all identified SNPs, except for -261M, modify the stability of the nucleic acid structure. A rather similar percentage of APS3 and APS4 patients had polymorphisms in the AIRE promoter. Conversely, there was no association between APS2 and AIRE promoter polymorphisms. Further AIRE promoter SNPs were found in 4 out of 5 patients with APS1 clinical diagnosis that did not harbor AIRE loss of function mutations. We hypothesize that AIRE promoter polymorphisms could contribute to APS predisposition, although this should be validated through genetic screening in larger patient cohorts and in vitro and in vivo functional studies.


Assuntos
Poliendocrinopatias Autoimunes , Humanos , Síndrome , Mutação , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
4.
Dev Dyn ; 252(9): 1162-1179, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37222488

RESUMO

BACKGROUND: Betaglycan, also known as the TGFß type III receptor (Tgfbr3), is a co-receptor that modulates TGFß family signaling. Tgfbr3 is upregulated during C2C12 myoblast differentiation and expressed in mouse embryos myocytes. RESULTS: To investigate tgfbr3 transcriptional regulation during zebrafish embryonic myogenesis, we cloned a 3.2 kb promoter fragment that drives reporter transcription during C2C12 myoblasts differentiation and in the Tg(tgfbr3:mCherry) transgenic zebrafish. We detect tgfbr3 protein and mCherry expression in the adaxial cells concomitantly with the onset of their radial migration to become slow-twitch muscle fibers in the Tg(tgfbr3:mCherry). Remarkably, this expression displays a measurable antero-posterior somitic gradient expression. CONCLUSIONS: tgfbr3 is transcriptionally regulated during somitic muscle development in zebrafish with an antero-posterior gradient expression that preferentially marks the adaxial cells and their descendants.


Assuntos
Somitos , Peixe-Zebra , Animais , Camundongos , Somitos/metabolismo , Proteoglicanas/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Desenvolvimento Muscular/fisiologia
5.
Curr Issues Mol Biol ; 45(5): 3933-3952, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37232720

RESUMO

The regulation of apoptosis (the programmed cell death) is dependent on the crucial involvement of BCL2 and BAX. The Bax-248G>A and Bcl-2-938 C>A polymorphic variations in the promoter sequences of the Bax and Bcl-2 gene have been recently associated with low Bax expression, progression to advanced stages, treatment resistance, and shortened overall survival rate in some hematological malignancies, including chronic myeloid leukemia (CML) and other myeloproliferative neoplasms. Chronic inflammation has been linked to various stages of carcinogenesis wherein pro-inflammatory cytokines play diverse roles in influencing cancer microenvironment leading to cell invasion and cancer progression. Cytokines such as TNF-α and IL-8 have been implicated in cancer growth in both solid and hematological malignancies with studies showing their elevated levels in patients. Genomic approaches have in recent years provided significant knowledge with the regard to the association of certain SNPs (single nucleotide polymerphisms) either in a gene or its promoter that can influence its expression, with the risk and susceptibility to human diseases including cancer. This study has investigated the consequences of promoter SNPs in apoptosis genes Bax-248G>A (rs4645878)/Bcl-2-938C>A (rs2279115) and pro-inflammatory cytokines TNF-α rs1800629 G>A/IL-8 rs4073 T>A on the risk and susceptibility towards hematological cancers. The study design has 235 individuals both male and female enrolled as subjects that had 113 cases of MPDs (myeloproliferative disorders) and 122 healthy individuals as controls. The genotyping studies were conducted through ARMS PCR (amplification-refractory mutation system PCR). The Bcl-2-938 C>A polymorphism showed up in 22% of patients in the study, while it was observed in only 10% of normal controls. This difference in genotype and allele frequency between the two groups was significant (p = 0.025). Similarly, the Bax-248G>A polymorphism was detected in 6.48% of the patients and 4.54% of the normal controls, with a significant difference in genotype and allele frequency between the groups (p = 0.048). The results suggest that the Bcl-2-938 C>A variant is linked to an elevated risk of MPDs in the codominant, dominant, and recessive inheritance models. Moreover, the study indicated allele A as risk allele which can significantly increase the risk of MPDs unlike the C allele. In case of Bax gene covariants, these were associated with an increased risk of MPDs in the codominant inheritance model and dominant inheritance model. It was found that the allele A significantly enhanced the risk of MPDs unlike the G allele. The frequencies of IL-8 rs4073 T>A in patients was found to be TT (16.39%), AT (36.88%) and AA (46.72%), compared to controls who were more likely to have frequencies of TT (39.34%), AT (37.70%) and AA (22.95%) as such, respectively. There was a notable overrepresentation of the AA genotype and GG homozygotes among patients compared to controls in TNF-α polymorphic variants, with 6.55% of patients having the AA genotype and 84% of patients being GG homozygotes, compared to 1.63% and 69%, respectively in controls. The data from the current study provide partial but important evidence that polymorphisms in apoptotic genes Bcl-2-938C>A and Bax-248G>A and pro-inflammatory cytokines IL-8 rs4073 T>A and TNF-α G>A may help predict the clinical outcomes of patients and determine the significance of such polymorphic variations in the risk of myeloproliferative diseases and their role as prognostic markers in disease management using a case-control study approach.

6.
Cell Biochem Funct ; 41(8): 1503-1513, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38014564

RESUMO

The role of tetraspanin CD81 in malignant transformation is best studied in colorectal cancer, and it appears that other transcripts beside the fully coding mRNA may also be dysregulated in malignant cells. Recent data from a comprehensive pan-cancer transcriptome analysis demonstrated differential activity of two alternative CD81 gene promoters in malignant versus nonmalignant gut mucosa. The promoter active in gut mucosa gives rise to transcripts CD81-203 and CD81-213, while the promoter active in colon and rectal cancer gives rise to transcripts CD81-205 and CD81-215. Our study aimed to explore the biomarker potential of the transcripts from the alternative CD81 gene promoters in colon cancer, as well as to investigate their structure and potential function using in silico tools. The analysis of the transcripts' expression in several colon cell lines cultivated in 2D and 3D and a set of colon cancer and healthy gut mucosa samples by qPCR and RNA sequencing suggested their low expression and stromal origin. Expression patterns in tumor and nontumor tissue along with in silico data suppose that the transcript CD81-215 may be a noncoding RNA of stromal origin with possible involvement in signaling related to malignant transformation.


Assuntos
Neoplasias do Colo , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Perfilação da Expressão Gênica , Transdução de Sinais , Tetraspanina 28/genética , Tetraspanina 28/metabolismo
7.
Int J Mol Sci ; 24(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37239961

RESUMO

HNF4α, a member of the nuclear receptor superfamily, regulates the genes involved in lipid and glucose metabolism. The expression of the RARß gene in the liver of HNF4α knock-out mice was higher versus wildtype controls, whereas oppositely, RARß promoter activity was 50% reduced by the overexpression of HNF4α in HepG2 cells, and treatment with retinoic acid (RA), a major metabolite of vitamin A, increased RARß promoter activity 15-fold. The human RARß2 promoter contains two DR5 and one DR8 binding motifs, as RA response elements (RARE) proximal to the transcription start site. While DR5 RARE1 was previously reported to be responsive to RARs but not to other nuclear receptors, we show here that mutation in DR5 RARE2 suppresses the promoter response to HNF4α and RARα/RXRα. Mutational analysis of ligand-binding pocket amino acids shown to be critical for fatty acid (FA) binding indicated that RA may interfere with interactions of FA carboxylic acid headgroups with side chains of S190 and R235, and the aliphatic group with I355. These results could explain the partial suppression of HNF4α transcriptional activation toward gene promoters that lack RARE, including APOC3 and CYP2C9, while conversely, HNF4α may bind to RARE sequences in the promoter of the genes such as CYP26A1 and RARß, activating these genes in the presence of RA. Thus, RA could act as either an antagonist towards HNF4α in genes lacking RAREs, or as an agonist for RARE-containing genes. Overall, RA may interfere with the function of HNF4α and deregulate HNF4α targets genes, including the genes important for lipid and glucose metabolism.


Assuntos
Fator 4 Nuclear de Hepatócito , Hepatócitos , Receptores do Ácido Retinoico , Tretinoína , Animais , Humanos , Camundongos , Glucose , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Lipídeos , Receptor alfa de Ácido Retinoico/genética , Tretinoína/farmacologia , Receptores do Ácido Retinoico/genética
8.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-38054227

RESUMO

Methylation of the O-6-methylguanine-DNA methyltransferase (MGMT) gene promoter is currently the most important prognostic biomarker in therapy of IDH-wild-type glioblastoma. One can obtain information about this methylation from total DNA methylation profile. OBJECTIVE: To analyze the DNA methylation signal intensity in the MGMT gene in samples of malignant gliomas and identify the most significant genomic positions for calculating the MGMT gene promoter status for further improvement of diagnostics and prediction of therapeutic options in patients with malignant gliomas. MATERIAL AND METHODS: The study is based on 43 samples (frozen tissue or paraffin blocks) from patients with malignant gliomas. Tumor DNA samples were prepared using the Illumina Infinium MethylationEPIC BeadChip Kit and the Illumina Next-Seq 550 Sequencing System platform. DNA methylation profiles were analyzed using computational algorithms in the R language, specialized libraries minfi and mgmtstp27, as well as basic statistical functions in the Rstudio environment. RESULTS: We established the MGMT gene promoter status in 43 samples of malignant gliomas considering total DNA methylation profile. In 24 samples (55%), the MGMT gene promoter was methylated. We compared methylation signal in certain CpG islands in groups with methylated and unmethylated MGMT gene promoters and identified the most significant positions for further improvement of data analysis algorithm. CONCLUSION: These data demonstrate the possibilities and prospects for further improvement of algorithm for analysis of the MGMT gene promoter status based on total DNA methylation profile in patients with malignant gliomas as an alternative to methyl-specific PCR. Our results are consistent with data of other neuro-oncology researchers. Indeed, computational methods like MGMT-STP27 are quite powerful and can be used in scientific and clinical practice to assess prognosis and make decisions about chemotherapy with alkylating agents.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Metilação de DNA/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Glioblastoma/genética , Prognóstico , O(6)-Metilguanina-DNA Metiltransferase/genética , DNA , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
9.
BMC Genomics ; 23(1): 516, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842574

RESUMO

BACKGROUND: Plant species from Rosaceae family are economically important. One of the major environmental factors impacting those species is cold stress. Although several Rosaceae plant genomes have recently been sequenced, there have been very few research conducted on cold upregulated genes and their promoter binding sites. In this study, we used computational approaches to identify and analyse potential cold stress response genes across ten Rosaceae family members. RESULTS: Cold stress upregulated gene data from apple and strawberry were used to identify syntelogs in other Rosaceae species. Gene duplication analysis was carried out to better understand the distribution of these syntelog genes in different Rosaceae members. A total of 11,145 popular abiotic stress transcription factor-binding sites were identified in the upstream region of these potential cold-responsive genes, which were subsequently categorised into distinct transcription factor (TF) classes. MYB classes of transcription factor binding site (TFBS) were abundant, followed by bHLH, WRKY, and AP2/ERF. TFBS patterns in the promoter regions were compared among these species and gene families, found to be quite different even amongst functionally related syntelogs. A case study on important cold stress responsive transcription factor family, AP2/ERF showed less conservation in TFBS patterns in the promoter regions. This indicates that syntelogs from the same group may be comparable at the gene level but not at the level of cis-regulatory elements. Therefore, for such genes from the same family, different repertoire of TFs could be recruited for regulation and expression. Duplication events must have played a significant role in the similarity of TFBS patterns amongst few syntelogs of closely related species. CONCLUSIONS: Our study overall suggests that, despite being from the same gene family, different combinations of TFs may play a role in their regulation and expression. The findings of this study will provide information about potential genes involved in the cold stress response, which will aid future functional research of these gene families involved in many important biological processes.


Assuntos
Resposta ao Choque Frio , Rosaceae , Resposta ao Choque Frio/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rosaceae/genética , Rosaceae/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Trends Genet ; 35(7): 542-551, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31130395

RESUMO

The cohesin protein complex mediates sister chromatid cohesion to ensure accurate chromosome segregation, and also influences gene transcription in higher eukaryotes. Modest deficits in cohesin function that do not alter chromosome segregation cause significant birth defects. The mechanisms by which cohesin participates in gene regulation have been studied in Drosophila, revealing that it is involved in gene activation by transcriptional enhancers and epigenetic gene silencing mediated by Polycomb group proteins. Recent studies reveal that early DNA replication origins are important for determining which genes associate with cohesin, and suggest that cohesin at replication origins is important for establishing both sister chromatid cohesion and enhancer-promoter communication.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/genética , Transcrição Gênica , Animais , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Regiões Promotoras Genéticas , Origem de Replicação , Troca de Cromátide Irmã , Coesinas
11.
Mol Carcinog ; 61(11): 1002-1015, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35975911

RESUMO

Parabens are a group of alkyl esters of p-hydroxybenzoic acid added to consumer products to prevent the growth of harmful bacteria and molds. Parabens are hypothesized to increase the risk of breast cancer (BC); however, no study has examined the interactions between parabens, global DNA methylation (DNAm), and BC risk. We examined the modifying effects of DNAm on the associations between parabens and BC, and whether parabens were associated with BC defined by tumor promoter methylation status. Participants included 708 cases and 598 controls from the Long Island Breast Cancer Study Project. Methylparaben (MPB), propylparaben, and butylparaben levels were measured in spot urine samples. Global DNAm was measured by analysis of long interspersed elementes-1 (LINE-1) and the luminometric methylation assay (LUMA). The promoter methylation status of 13 genes was measured in tumor samples from 509 cases. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between parabens and BC stratified by LINE-1/LUMA, and between parabens and gene-specific promoter methylation-defined BC. Outcome heterogeneity was evaluated using ratios of ORs (RORs). We assessed the joint effects of the multiple parabens using quantile g-computation. The highest versus lowest tertile of MPB and a one-quantile increase in all parabens were associated with ORs of 1.46 (95% CI = 0.96-2.23) and 1.32 (95% CI = 1.02-1.71), respectively, among women with hypomethylated LINE-1. A one-ln unit increase in MPB was associated with a 25% increase in the odds of hypomethylated (vs. hypermethylated) CCND2 promoter-defined BC (ROR = 1.25, 95% CI = 1.06-1.48), and a one-quantile increase in all parabens was associated with a 55% increase in the odds of hypomethylated (vs. hypermethylated) CCND2 promoter-defined BC (ROR = 1.55, 95% CI = 1.04-2.32). Exposure to parabens may increase the risk of BC among women with hypomethylated global DNAm and may increase the risk of tumors with gene-specific hypomethylated promoter regions.


Assuntos
Neoplasias da Mama , Metilação de DNA , Feminino , Humanos , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Carcinógenos/toxicidade , Eletrólitos , Modelos Logísticos , Parabenos/toxicidade , Regiões Promotoras Genéticas
12.
Planta ; 256(4): 69, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066773

RESUMO

MAIN CONCLUSION: The pUceS8.3 is a constitutive gene promoter with potential for ectopic and strong genes overexpression or active biomolecules in plant tissues attacked by pests, including nematode-induced giant cells or galls. Soybean (Glycine max) is one of the most important agricultural commodities worldwide and a major protein and oil source. Herein, we identified the soybean ubiquitin-conjugating (E2) enzyme gene (GmUBC4; Glyma.18G216000), which is significantly upregulated in response to Anticarsia gemmatalis attack and Meloidogyne incognita-induced galls during plant parasitism by plant nematode. The GmUBC4 promoter sequence and its different modules were functionally characterized in silico and in planta using transgenic Arabidopsis thaliana and G. max lines. Its full-length transcriptional regulatory region (promoter and 5´-UTR sequences, named pUceS8.3 promoter) was able to drive higher levels of uidA (ß-glucuronidase) gene expression in different tissues of transgenic A. thaliana lines compared to its three shortened modules and the p35SdAMV promoter. Notably, higher ß-glucuronidase (GUS) enzymatic activity was shown in M. incognita-induced giant cells when the full pUceS8.3 promoter drove the expression of this reporter gene. Furthermore, nematode-specific dsRNA molecules were successfully overexpressed under the control of the pUceS8.3 promoter in transgenic soybean lines. The RNAi gene construct used here was designed to post-transcriptionally downregulate the previously characterized pre-mRNA splicing factor genes from Heterodera glycines and M. incognita. A total of six transgenic soybean lines containing RNAi gene construct were selected for molecular characterization after infection with M. incognita pre-parasitic second-stage (ppJ2) nematodes. A strong reduction in the egg number produced by M. incognita after parasitism was observed in those transgenic soybean lines, ranging from 71 to 92% compared to wild-type control plants. The present data demonstrated that pUceS8.3 is a gene promoter capable of effectively driving dsRNA overexpression in nematode-induced giant cells of transgenic soybean lines and can be successfully applied as an important biotechnological asset to generate transgenic crops with improved resistance to root-knot nematodes as well as other pests.


Assuntos
Arabidopsis , Tylenchoidea , Animais , Arabidopsis/genética , Glucuronidase/genética , Plantas Geneticamente Modificadas/genética , RNA de Cadeia Dupla/genética , Glycine max/genética , Tylenchoidea/genética
13.
Inflamm Res ; 71(1): 119-129, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34787682

RESUMO

OBJECTIVE: Odontogenic ameloblast-associated protein (ODAM) is produced by maturation stage ameloblasts and junctional epithelium (JE). The function of ODAM is thought to be involved in the attachment of teeth and JE. To elucidate transcriptional regulation of human ODAM gene in inflamed gingiva, we have analyzed the effects of TNF-α on the expression of ODAM gene in Ca9-22 and Sa3 gingival epithelial cells. MATERIALS AND METHODS: Total RNAs were extracted from Ca9-22 and Sa3 cells after stimulation by TNF-α (10 ng/ml). ODAM mRNA and protein levels were analyzed by qPCR and Western blotting. Luciferase (LUC) analyses were performed using LUC constructs inserted in various lengths of ODAM gene promoter. Gel shift and chromatin immunoprecipitation (ChIP) assays were carried out. RESULTS: TNF-α increased ODAM mRNA and protein levels at 3 to 24 h. TNF-α induced LUC activities of the ODAM gene promoter constructs, and the activities were inhibited by protein kinase A, tyrosine kinase, MEK1/2, PI3-kinase and NF-κB inhibitors. Gel shift and ChIP assays revealed that TNF-α increased CCAAT/enhancer-binding protein (C/EBP) ß and Yin Yang1 (YY1) binding to three kinds of C/EBPs and YY1 elements. CONCLUSION: These results demonstrate that TNF-α stimulates ODAM gene transcription via C/EBPs and YY1 elements in the human ODAM gene promoter.


Assuntos
Ameloblastos , Fator de Necrose Tumoral alfa , Ameloblastos/metabolismo , Inserção Epitelial/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas I-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
14.
Odontology ; 110(3): 557-568, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35179670

RESUMO

Junction epithelium (JE) is located apical to the bottom of the gingival sulcus and binds enamel to hemidesmosomes to protect the periodontal tissue from bacterial infection. Function of odontogenic ameloblast-associated protein (ODAM) is suggested by its expression sites (JE and maturation stage ameloblasts) to be involved in the adhesion between the JE and enamel, and odontogenesis. To analyze the changes in ODAM gene and protein expressions in inflamed gingiva, Ca9-22 gingival epithelial cells were stimulated with 1 ng/ml interleukin-1ß (IL-1ß) for 3-24 h, and ODAM mRNA and protein levels were analyzed by real-time PCR and Western blotting. Luciferase (LUC) constructs were made ligating various lengths of human ODAM gene promoters and performed LUC analyses in Ca9-22 cells. Gel shift and chromatin immunoprecipitation (ChIP) assays were performed. IL-1ß induced ODAM mRNA and protein levels at 6-24 h. IL-1ß increased LUC activities of the ODAM gene promoter constructs from - 85 to - 950. These activities were blocked by protein kinase A, tyrosine kinase, mitogen-activated protein (MAP) kinase kinase and phosphoinositide 3-kinase inhibitors. Gel shift and ChIP assays showed that IL-1ß induced CCAAT/enhancer-binding protein (C/EBP) ß and Yin Yang1 (YY1) binding to C/EBP1, 2, 3, and YY1 elements. These data indicate that IL-1ß stimulates ODAM gene transcription mediated through C/EBP1, C/EBP2, C/EBP3, and YY1 elements in the human ODAM gene promoter.


Assuntos
Ameloblastos , Gengiva , Ameloblastos/metabolismo , Células Epiteliais/metabolismo , Humanos , Interleucina-1beta/metabolismo , Interleucina-1beta/farmacologia , Odontogênese , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/metabolismo , Transcrição Gênica
15.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32641480

RESUMO

We previously reported that the cellular transcription factor hypoxia-inducible factor 1α (HIF-1α) binds a hypoxia response element (HRE) located within the promoter of Epstein-Barr virus's (EBV's) latent-lytic switch BZLF1 gene, Zp, inducing viral reactivation. In this study, EBV-infected cell lines derived from gastric cancers and Burkitt lymphomas were incubated with HIF-1α-stabilizing drugs: the iron chelator deferoxamine (Desferal [DFO]), a neddylation inhibitor (pevonedistat [MLN-4924]), and a prolyl hydroxylase inhibitor (roxadustat [FG-4592]). DFO and MLN-4924, but not FG-4592, induced accumulation of both lytic EBV proteins and phosphorylated p53 in cell lines that contain a wild-type p53 gene. FG-4592 also failed to activate transcription from Zp in a reporter assay despite inducing accumulation of HIF-1α and transcription from another HRE-containing promoter. Unexpectedly, DFO failed to induce EBV reactivation in cell lines that express mutant or no p53 or when p53 expression was knocked down with short hairpin RNAs (shRNAs). Likewise, HIF-1α failed to activate transcription from Zp when p53 was knocked out by CRISPR-Cas9. Importantly, DFO induced binding of p53 as well as HIF-1α to Zp in chromatin immunoprecipitation (ChIP) assays, but only when the HRE was present. Nutlin-3, a drug known to induce accumulation of phosphorylated p53, synergized with DFO and MLN-4924 in inducing EBV reactivation. Conversely, KU-55933, a drug that inhibits ataxia telangiectasia mutated, thereby preventing p53 phosphorylation, inhibited DFO-induced EBV reactivation. Lastly, activation of Zp transcription by DFO and MLN-4924 mapped to its HRE. Thus, we conclude that induction of BZLF1 gene expression by HIF-1α requires phosphorylated, wild-type p53 as a coactivator, with HIF-1α binding recruiting p53 to Zp.IMPORTANCE EBV, a human herpesvirus, is latently present in most nasopharyngeal carcinomas, Burkitt lymphomas, and some gastric cancers. To develop a lytic-induction therapy for treating patients with EBV-associated cancers, we need a way to efficiently reactivate EBV into lytic replication. EBV's BZLF1 gene product, Zta, usually controls this reactivation switch. We previously showed that HIF-1α binds the BZLF1 gene promoter, inducing Zta synthesis, and HIF-1α-stabilizing drugs can induce EBV reactivation. In this study, we determined which EBV-positive cell lines are reactivated by classes of HIF-1α-stabilizing drugs. We found, unexpectedly, that HIF-1α-stabilizing drugs only induce reactivation when they also induce accumulation of phosphorylated, wild-type p53. Fortunately, p53 phosphorylation can also be provided by drugs such as nutlin-3, leading to synergistic reactivation of EBV. These findings indicate that some HIF-1α-stabilizing drugs may be helpful as part of a lytic-induction therapy for treating patients with EBV-positive malignancies that contain wild-type p53.


Assuntos
Herpesvirus Humano 4/genética , Interações Hospedeiro-Patógeno/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Transativadores/genética , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Ciclopentanos/farmacologia , Desferroxamina/farmacologia , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Regulação da Expressão Gênica , Glicina/análogos & derivados , Glicina/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/crescimento & desenvolvimento , Herpesvirus Humano 4/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/agonistas , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Quelantes de Ferro/farmacologia , Isoquinolinas/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/virologia , Morfolinas/farmacologia , Piperazinas/farmacologia , Inibidores de Prolil-Hidrolase/farmacologia , Regiões Promotoras Genéticas , Ligação Proteica/efeitos dos fármacos , Pirimidinas/farmacologia , Pironas/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Elementos de Resposta , Transdução de Sinais , Transativadores/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Ativação Viral/efeitos dos fármacos
16.
Pediatr Allergy Immunol ; 32(3): 552-559, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33179333

RESUMO

BACKGROUND: Interleukin 10 has been shown to play a critical role in the regulation of the immune responses in allergic diseases. AIM: To investigate if genetic polymorphisms in the promoter region of the IL-10 gene are associated with food allergy (FA) susceptibility in Caucasian pediatric patients with concomitant allergic diseases and IL-10 levels. METHODS: The single nucleotide polymorphisms (SNPs) at -1082A > G (rs1800896), -819 T > C (rs1800871), and -592A > C (rs1800872) of 62 pediatric patients with IgE-mediated FA were analyzed and correlated with clinical parameters, serum IgE and IL-10 levels. The results were compared with those of 92 healthy controls without FA, personal and/or family history of atopy. RESULTS: Analysis and comparison of genotype distributions, allele frequencies, and haplotypes showed that none of the genotypes confers an increased risk of FA. The genotype -1082 AA in FA patients was associated with moderate to severe symptoms of FA, the development of atopic asthma, and higher levels of IL-10. In a linear regression study, we confirmed that the genotype -1082 AA acts as an independent factor for the higher levels of IL-10. A positive association was also observed between -819T/C and -592 A/C SNPs and later onset of FA. CONCLUSION: Polymorphisms in the promoter region of the IL-10 gene are not associated with FA susceptibility in our cohort. In FA patients, -1082 A/G SNPs seem to influence the production of IL-10, the severity of FA symptoms, and the development of atopic asthma in this population.


Assuntos
Hipersensibilidade Alimentar , Interleucina-10 , Estudos de Casos e Controles , Criança , Hipersensibilidade Alimentar/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
17.
Microb Cell Fact ; 20(1): 15, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468127

RESUMO

Genetic modification of Rhodococcus jostii RHA1 was carried out in order to optimise the production of pyridine-2,4-dicarboxylic acid and pyridine-2,5-dicarboxylic acid bioproducts from lignin or lignocellulose breakdown, via insertion of either the Sphingobium SYK-6 ligAB genes or Paenibacillus praA gene respectively. Insertion of inducible plasmid pTipQC2 expression vector containing either ligAB or praA genes into a ΔpcaHG R. jostii RHA1 gene deletion strain gave 2-threefold higher titres of PDCA production from lignocellulose (200-287 mg/L), compared to plasmid expression in wild-type R. jostii RHA1. The ligAB genes were inserted in place of the chromosomal pcaHG genes encoding protocatechuate 3,4-dioxygenase, under the control of inducible Picl or PnitA promoters, or a constitutive Ptpc5 promoter, producing 2,4-PDCA products using either wheat straw lignocellulose or commercial soda lignin as carbon source. Insertion of Amycolatopsis sp. 75iv2 dyp2 gene on a pTipQC2 expression plasmid led to enhanced titres of 2,4-PDCA products, due to enhanced rate of lignin degradation. Growth in minimal media containing wheat straw lignocellulose led to the production of 2,4-PDCA in 330 mg/L titre in 40 h, with > tenfold enhanced productivity, compared with plasmid-based expression of ligAB genes in wild-type R. jostii RHA1. Production of 2,4-PDCA was also observed using several different polymeric lignins as carbon sources, and a titre of 240 mg/L was observed using a commercially available soda lignin as feedstock.


Assuntos
Ácidos Dicarboxílicos/metabolismo , Lignina/metabolismo , Engenharia Metabólica/métodos , Piridinas/metabolismo , Rhodococcus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbono/metabolismo , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Redes e Vias Metabólicas/genética , Família Multigênica/genética , Regiões Promotoras Genéticas/genética , Protocatecoate-3,4-Dioxigenase/genética , Protocatecoate-3,4-Dioxigenase/metabolismo , Rhodococcus/genética
18.
Mol Biol Rep ; 48(11): 7147-7152, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34591267

RESUMO

BACKGROUND: The promoter region is a key element of gene expression regulation. In mammals, most of the genes present, at the level of their promoter, a large number of islands CpG. Age also is seen as another factor for developing breast cell cancer reaching the tumour stage. AIM: This study aimed to explore the hypermethylation of the BRCA1/2 promoter gene in women breast cancer and correlation with age and tumour stage. MATERIALS AND METHODS: Fifty biopsies were derived from Moroccan women treated for breast carcinoma, the DNA extracted was treated by bisulphite and the targeted BRCA1/2 Amplicons were amplified by specific methylation primers (MSP). RESULTS: The result shows that 62% of the samples were BRCA1 methylated in addition and negative result for BRCA2, these positive epigenetic factor were remarkable in women over 47 years and at the stage of malignant tumour. CONCLUSION: These results show that half of the methylated samples are positive with a majority of over 47 years old, and confirms that age might be an additional factor for breast cancer development.


Assuntos
Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Neoplasias da Mama/metabolismo , Metilação de DNA , DNA de Neoplasias/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Regiões Promotoras Genéticas , Adulto , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , DNA de Neoplasias/genética , Feminino , Humanos , Pessoa de Meia-Idade , Marrocos
19.
Brain ; 143(3): 891-905, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32129831

RESUMO

Epilepsy is a major health burden, calling for new mechanistic insights and therapies. CRISPR-mediated gene editing shows promise to cure genetic pathologies, although hitherto it has mostly been applied ex vivo. Its translational potential for treating non-genetic pathologies is still unexplored. Furthermore, neurological diseases represent an important challenge for the application of CRISPR, because of the need in many cases to manipulate gene function of neurons in situ. A variant of CRISPR, CRISPRa, offers the possibility to modulate the expression of endogenous genes by directly targeting their promoters. We asked if this strategy can effectively treat acquired focal epilepsy, focusing on ion channels because their manipulation is known be effective in changing network hyperactivity and hypersynchronziation. We applied a doxycycline-inducible CRISPRa technology to increase the expression of the potassium channel gene Kcna1 (encoding Kv1.1) in mouse hippocampal excitatory neurons. CRISPRa-mediated Kv1.1 upregulation led to a substantial decrease in neuronal excitability. Continuous video-EEG telemetry showed that AAV9-mediated delivery of CRISPRa, upon doxycycline administration, decreased spontaneous generalized tonic-clonic seizures in a model of temporal lobe epilepsy, and rescued cognitive impairment and transcriptomic alterations associated with chronic epilepsy. The focal treatment minimizes concerns about off-target effects in other organs and brain areas. This study provides the proof-of-principle for a translational CRISPR-based approach to treat neurological diseases characterized by abnormal circuit excitability.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Disfunção Cognitiva/genética , Disfunção Cognitiva/prevenção & controle , Epilepsia do Lobo Temporal/prevenção & controle , Edição de Genes/métodos , Canal de Potássio Kv1.1/biossíntese , Adenoviridae , Animais , Eletroencefalografia , Epilepsia do Lobo Temporal/complicações , Feminino , Hipocampo/metabolismo , Masculino , Potenciais da Membrana/genética , Potenciais da Membrana/fisiologia , Camundongos , Neurônios/fisiologia , Cultura Primária de Células , Transfecção , Regulação para Cima
20.
Odontology ; 109(2): 403-410, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32980912

RESUMO

Amelotin (AMTN) is an enamel protein that is localized in junctional epithelium (JE) of gingiva and suggested to be involved in the attachment between JE and tooth enamel. MicroRNA is a small non-coding RNA that regulates gene expression at post-transcriptional level by binding to the 3'-untranslated region (3'-UTR) of target mRNAs. In this study, we have analyzed the effects of miR-200b on the expression of AMTN in human gingival epithelial (Ca9-22) cells. Total RNAs and proteins were extracted from Ca9-22 cells transfected with miR-200b expression plasmid or miR-200b inhibitor and stimulated by TNF-α (10 ng/ml, 12 h). AMTN and inhibitor of kappa-B kinase beta (IKKß) mRNA and protein levels were measured by qPCR and Western blot. Human AMTN 3'-UTR that contains putative miR-200b target sites were cloned downstream of -353AMTN luciferase (LUC) plasmid. Ca9-22 cells were transfected with -353AMTN 3'-UTR LUC constructs and miR-200b expression plasmid, and LUC activities were measured with or without stimulation by TNF-α. TNF-α-induced AMTN mRNA levels were partially inhibited by miR-200b overexpression and enhanced by miR-200b inhibitor. TNF-α-induced IKKß mRNA and protein levels were almost completely inhibited by miR-200b. Transcriptional activities of -353AMTN 3'-UTR LUC constructs were induced by TNF-α and partially inhibited by miR-200b. IKKß inhibitor IMD0354 and NF-κB inhibitor triptolide decreased TNF-α-induced LUC activities. Furthermore, both inhibitors reduced AMTN mRNA levels in the presence or absence of TNF-α. These results suggest that miR-200b suppresses AMTN expression by targeting to AMTN and IKKß mRNAs in the human gingival epithelial cells.


Assuntos
Proteínas do Esmalte Dentário , MicroRNAs , Proteínas do Esmalte Dentário/genética , Células Epiteliais , Gengiva , Humanos , MicroRNAs/genética , Fator de Necrose Tumoral alfa/genética
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