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1.
Nucleic Acids Res ; 51(10): 4845-4866, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-36929452

RESUMO

The action of cis-regulatory elements with either activation or repression functions underpins the precise regulation of gene expression during normal development and cell differentiation. Gene activation by the combined activities of promoters and distal enhancers has been extensively studied in normal and pathological contexts. In sharp contrast, gene repression by cis-acting silencers, defined as genetic elements that negatively regulate gene transcription in a position-independent fashion, is less well understood. Here, we repurpose the STARR-seq approach as a novel high-throughput reporter strategy to quantitatively assess silencer activity in mammals. We assessed silencer activity from DNase hypersensitive I sites in a mouse T cell line. Identified silencers were associated with either repressive or active chromatin marks and enriched for binding motifs of known transcriptional repressors. CRISPR-mediated genomic deletions validated the repressive function of distinct silencers involved in the repression of non-T cell genes and genes regulated during T cell differentiation. Finally, we unravel an association of silencer activity with short tandem repeats, highlighting the role of repetitive elements in silencer activity. Our results provide a general strategy for genome-wide identification and characterization of silencer elements.


Assuntos
Elementos Silenciadores Transcricionais , Linfócitos T , Animais , Camundongos , Elementos Silenciadores Transcricionais/genética , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo , Sequências Reguladoras de Ácido Nucleico , Repetições de Microssatélites , Mamíferos/genética
2.
J Infect Dis ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531688

RESUMO

BACKGROUND: GWAS have identified several non-functional tagSNPs associated with severe malaria. We hypothesized that causal SNPs could play a significant role in severe malaria by altering promoter or enhancer activity. Here, we sought to identify such regulatory SNPs. METHODS: SNPs in linkage disequilibrium with tagSNPs associated with severe malaria were identified and were further annotated using FUMA. Then, SNPs were prioritized using IW-scoring method to identify regulatory ones. Gene reporter assays were performed to assess the regulatory effect of a region containing candidates. The association between SNPs and severe malaria was assessed using logistic regression models in a Senegalese cohort. RESULTS: Among 418 SNPs, the best candidates were rs116525449 and rs79644959, which were in full disequilibrium between them, and located within the ARL14 promoter. Our gene reporter assay results revealed that the region containing the SNPs exhibited cell-specific promoter or enhancer activity, while the SNPs influenced promoter activity. We detected an association between severe malaria and those two SNPs using the overdominance model and we replicated the association of severe malaria with the tagSNP rs116423146. CONCLUSIONS: We suggest that these SNPs regulate ARL14 expression in immune cells and the presentation of antigens to T lymphocytes, thus influencing severe malaria development.

3.
Int J Mol Sci ; 24(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37958695

RESUMO

Antibodies play a crucial role in activating protective immunity against malaria by interacting with Fc-gamma receptors (FcγRs). Genetic variations in genes encoding FcγRs can affect immune cell responses to the parasite. In this study, our aim was to investigate whether non-coding variants that regulate FcγR expression could influence the prevalence of Plasmodium falciparum infection. Through bioinformatics approaches, we selected expression quantitative trait loci (eQTL) for FCGR2A, FCGR2B, FCGR2C, FCGR3A, and FCGR3B genes encoding FcγRs (FCGR), in whole blood. We prioritized two regulatory variants, rs2099684 and rs1771575, located in open genomic regions. These variants were identified using RegVar, ImmuNexUT, and transcription factor annotations specific to immune cells. In addition to these, we genotyped the coding variants FCGR2A/rs1801274 and FCGR2B/rs1050501 in 234 individuals from a malaria-endemic area in Burkina Faso. We conducted age and family-based analyses to evaluate associations with the prevalence of malarial infection in both children and adults. The analysis revealed that the regulatory rs1771575-CC genotype was predicted to influence FCGR2B/FCGR2C/FCGR3A transcripts in immune cells and was the sole variant associated with a higher prevalence of malarial infection in children. In conclusion, this study identifies the rs1771575 cis-regulatory variant affecting several FcγRs in myeloid and neutrophil cells and associates it with the inter-individual capacity of children living in Burkina Faso to control malarial infection.


Assuntos
Malária Falciparum , Receptores de IgG , Adulto , Criança , Humanos , Burkina Faso/epidemiologia , Malária Falciparum/epidemiologia , Malária Falciparum/genética , Família Multigênica , Plasmodium falciparum/genética , Receptores de IgG/genética
4.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055007

RESUMO

Mortality due to sepsis remains unacceptably high, especially for septic shock patients. Murine models have been used to better understand pathophysiology mechanisms. However, the mouse model is still under debate. Herein we investigated the transcriptional response of mice injected with lipopolysaccharide (LPS) and compared it to either human cells stimulated in vitro with LPS or to the blood cells of septic patients. We identified a molecular signature composed of 2331 genes with an FDR median of 0%. This molecular signature is highly enriched in regulated genes in peritoneal macrophages stimulated with LPS. There is significant enrichment in several inflammatory signaling pathways, and in disease terms, such as pneumonia, sepsis, systemic inflammatory response syndrome, severe sepsis, an inflammatory disorder, immune suppression, and septic shock. A significant overlap between the genes upregulated in mouse and human cells stimulated with LPS has been demonstrated. Finally, genes upregulated in mouse cells stimulated with LPS are enriched in genes upregulated in human cells stimulated in vitro and in septic patients, who are at high risk of death. Our results support the hypothesis of common molecular and cellular mechanisms between mouse and human sepsis.


Assuntos
Suscetibilidade a Doenças , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Sepse/etiologia , Transcrição Gênica , Animais , Biomarcadores , Biologia Computacional/métodos , Citocinas/metabolismo , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/efeitos adversos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Sepse/diagnóstico , Sepse/metabolismo
5.
Int J Mol Sci ; 23(9)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35563239

RESUMO

Genome-wide association studies for severe malaria (SM) have identified 30 genetic variants mostly located in non-coding regions. Here, we aimed to identify potential causal genetic variants located in these loci and demonstrate their functional activity. We systematically investigated the regulatory effect of the SNPs in linkage disequilibrium (LD) with the malaria-associated genetic variants. Annotating and prioritizing genetic variants led to the identification of a regulatory region containing five ATP2B4 SNPs in LD with rs10900585. We found significant associations between SM and rs10900585 and our candidate SNPs (rs11240734, rs1541252, rs1541253, rs1541254, and rs1541255) in a Senegalese population. Then, we demonstrated that both individual SNPs and the combination of SNPs had regulatory effects. Moreover, CRISPR/Cas9-mediated deletion of this region decreased ATP2B4 transcript and protein levels and increased Ca2+ intracellular concentration in the K562 cell line. Our data demonstrate that severe malaria-associated genetic variants alter the expression of ATP2B4 encoding a plasma membrane calcium-transporting ATPase 4 (PMCA4) expressed on red blood cells. Altering the activity of this regulatory element affects the risk of SM, likely through calcium concentration effect on parasitaemia.


Assuntos
Estudo de Associação Genômica Ampla , Malária , Predisposição Genética para Doença , Humanos , Malária/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Polimorfismo de Nucleotídeo Único , Sequências Reguladoras de Ácido Nucleico
6.
J Clin Immunol ; 41(5): 1048-1063, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33660144

RESUMO

Cardiomyopathies are an important cause of heart failure and sudden cardiac death. Little is known about the role of rare genetic variants in inflammatory cardiomyopathy. Chronic Chagas disease cardiomyopathy (CCC) is an inflammatory cardiomyopathy prevalent in Latin America, developing in 30% of the 6 million patients chronically infected by the protozoan Trypanosoma cruzi, while 60% remain free of heart disease (asymptomatic (ASY)). The cytokine interferon-γ and mitochondrial dysfunction are known to play a major pathogenetic role. Chagas disease provides a unique model to probe for genetic variants involved in inflammatory cardiomyopathy. METHODS: We used whole exome sequencing to study nuclear families containing multiple cases of Chagas disease. We searched for rare pathogenic variants shared by all family members with CCC but absent in infected ASY siblings and in unrelated ASY. RESULTS: We identified heterozygous, pathogenic variants linked to CCC in all tested families on 22 distinct genes, from which 20 were mitochondrial or inflammation-related - most of the latter involved in proinflammatory cytokine production. Significantly, incubation with IFN-γ on a human cardiomyocyte line treated with an inhibitor of dihydroorotate dehydrogenase brequinar (enzyme showing a loss-of-function variant in one family) markedly reduced mitochondrial membrane potential (ΔψM), indicating mitochondrial dysfunction. CONCLUSION: Mitochondrial dysfunction and inflammation may be genetically determined in CCC, driven by rare genetic variants. We hypothesize that CCC-linked genetic variants increase mitochondrial susceptibility to IFN-γ-induced damage in the myocardium, leading to the cardiomyopathy phenotype in Chagas disease. This mechanism may also be operative in other inflammatory cardiomyopathies.


Assuntos
Cardiomiopatia Chagásica/genética , Inflamação/genética , Mitocôndrias/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Sequenciamento do Exoma
7.
Glycobiology ; 28(7): 534-541, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718295

RESUMO

The HS3ST3A1/B1 genes encode two homologous 3-O-sulfotransferases involved in the late modification step during heparan sulfate (HS) biosynthesis. In addition to the single nucleotide polymorphisms (SNPs) rs28470223 (C > T) in the promoter region of both HS3ST3A1 and rs62636623 (Gly/Arg) in the stem region of HS3ST3B1, three missense mutations (rs62056073, rs61729712 and rs9906590) located within the catalytic sulfotransferase domain of 3-OST-B1 are linked and associated to Plasmodium falciparum parasitaemia. To ascertain the functional effects of these SNP associations, we investigated the regulatory effect of rs28470223 and characterized the enzymatic activity of the missense SNP rs61729712 (Ser279Asn) localized at proximity of the substrate binding cleft. The SNP rs28470223 results in decreased promoter activity of HS3ST3A1 in K562 cells, suggesting a reduced in vivo transcription activity of the target gene. A comparative kinetic analysis of wt HS3ST3B1 and the Ser269Asn variant (rs61729712) using a HS-derived oligosaccharide substrate reveals a slightly higher catalytic activity for the SNP variant. These genetic and enzymatic studies suggest that genetic variations in enzymes responsible of HS 3-O-sulfation can modulate their promoter and enzymatic activities and may influence P. falciparum parasitaemia.


Assuntos
Parasitemia/genética , Plasmodium falciparum , Polimorfismo de Nucleotídeo Único , Sulfotransferases/genética , Sítios de Ligação , Linhagem Celular Tumoral , Heparitina Sulfato/metabolismo , Humanos , Mutação de Sentido Incorreto , Ligação Proteica , Sulfotransferases/química , Sulfotransferases/metabolismo
8.
Crit Care Med ; 46(7): e684-e691, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29634521

RESUMO

OBJECTIVES: To investigate any gender effect of the beta-1 adrenergic blocker, landiolol, on cardiac performance and energy metabolism in septic rats, and to explore the expression of genes and proteins involved in this process. DESIGN: Randomized animal study. SETTING: University research laboratory. SUBJECTS: Male and female Wistar rats. INTERVENTIONS: One hour after cecal ligation and puncture, male and female rats were randomly allocated to the following groups: sham male, cecal ligation and puncture male, cecal ligation and puncture + landiolol male, sham female, cecal ligation and puncture female, and cecal ligation and puncture + landiolol female. Cardiac MRI was carried out 18 hours after cecal ligation and puncture to assess in vivo cardiac function. Ex vivo cardiac function measurement and P magnetic resonance spectroscopy were subsequently performed using an isovolumic isolated heart preparation. Finally, we assessed cardiac gene and protein expression. MEASUREMENTS AND MAIN RESULTS: In males, landiolol increased indexed stroke volume by reversing the indexed end-diastolic volume reduction without affecting left ventricle ejection fraction. In females, landiolol did not increase indexed stroke volume and indexed end-diastolic volume but decreased left ventricle ejection fraction. Landiolol had no effect on ex vivo cardiac function and on high-energy phosphate compounds. The effect of landiolol on the gene expression of natriuretic peptide receptor 3 and on protein expression of phosphorylated-AKT:AKT ratio and endothelial nitric oxide synthase was different in males and females. CONCLUSIONS: Landiolol improved the in vivo cardiac performance of septic male rats while deleterious effects were reported in females. Expression of natriuretic peptide receptor 3, phosphorylated-AKT:AKT, and endothelial nitric oxide synthase are signaling pathways to investigate to better understand the sex differences in sepsis.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Morfolinas/uso terapêutico , Sepse/tratamento farmacológico , Ureia/análogos & derivados , Animais , Feminino , Coração/diagnóstico por imagem , Coração/efeitos dos fármacos , Coração/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Wistar , Fatores Sexuais , Volume Sistólico/efeitos dos fármacos , Resultado do Tratamento , Ureia/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos
9.
Hum Mol Genet ; 24(1): 197-212, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25158689

RESUMO

Long-term exposure to environmental oxidative stressors, like the herbicide paraquat (PQ), has been linked to the development of Parkinson's disease (PD), the most frequent neurodegenerative movement disorder. Paraquat is thus frequently used in the fruit fly Drosophila melanogaster and other animal models to study PD and the degeneration of dopaminergic neurons (DNs) that characterizes this disease. Here, we show that a D1-like dopamine (DA) receptor, DAMB, actively contributes to the fast central nervous system (CNS) failure induced by PQ in the fly. First, we found that a long-term increase in neuronal DA synthesis reduced DAMB expression and protected against PQ neurotoxicity. Secondly, a striking age-related decrease in PQ resistance in young adult flies correlated with an augmentation of DAMB expression. This aging-associated increase in oxidative stress vulnerability was not observed in a DAMB-deficient mutant. Thirdly, targeted inactivation of this receptor in glutamatergic neurons (GNs) markedly enhanced the survival of Drosophila exposed to either PQ or neurotoxic levels of DA, whereas, conversely, DAMB overexpression in these cells made the flies more vulnerable to both compounds. Fourthly, a mutation in the Drosophila ryanodine receptor (RyR), which inhibits activity-induced increase in cytosolic Ca(2+), also strongly enhanced PQ resistance. Finally, we found that DAMB overexpression in specific neuronal populations arrested development of the fly and that in vivo stimulation of either DNs or GNs increased PQ susceptibility. This suggests a model for DA receptor-mediated potentiation of PQ-induced neurotoxicity. Further studies of DAMB signaling in Drosophila could have implications for better understanding DA-related neurodegenerative disorders in humans.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Síndromes Neurotóxicas/metabolismo , Paraquat/toxicidade , Receptores de Dopamina D1/metabolismo , Fatores Etários , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Exposição Ambiental , Feminino , Humanos , Doença de Parkinson , Receptores Dopaminérgicos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética
10.
PLoS Genet ; 8(11): e1003081, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209438

RESUMO

Cardiac aging is a complex process, which is influenced by both environmental and genetic factors. Deciphering the mechanisms involved in heart senescence therefore requires identifying the molecular pathways that are affected by age in controlled environmental and genetic conditions. We describe a functional genomic investigation of the genetic control of cardiac senescence in Drosophila. Molecular signatures of heart aging were identified by differential transcriptome analysis followed by a detailed bio-informatic analysis. This approach implicated the JNK/dJun pathway and the transcription factor Vri/dNFIL3 in the transcription regulatory network involved in cardiac senescence and suggested the possible involvement of oxidative stress (OS) in the aging process. To validate these predictions, we developed a new in vivo assay to analyze heart performance in various contexts of adult heart-specific gene overexpression and inactivation. We demonstrate that, as in mammals, OS plays a central role in cardiac senescence, and we show that pharmacological interventions impinging on OS slow heart senescence. These observations strengthen the idea that cardiac aging is controlled by evolutionarily conserved mechanisms, further validating Drosophila as a model to study cardiac senescence. In addition, we demonstrate that Vri, the ortholog of the vertebrate NFIL3/E4B4 transcription factor, is a major genetic regulator of cardiac aging. Vri overexpression leads to major heart dysfunctions, but its loss of function significantly reduces age-related cardiac dysfunctions. Furthermore, we unambiguously show that the JNK/AP1 pathway, the role of which in cardiac aging in mammals is controversial, is activated during cardiac aging and has a detrimental effect on cardiac senescence. This data-driven functional genomic analysis therefore led to the identification of key components of the Gene Regulatory Network of cardiac aging in Drosophila and may prompt to investigate the involvement of their counterparts in the cardiac aging process in mammals.


Assuntos
Envelhecimento , Proteínas de Drosophila , Drosophila melanogaster , Coração/fisiologia , Sistema de Sinalização das MAP Quinases/genética , Fatores de Transcrição , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Regulação da Expressão Gênica , Humanos , Estresse Oxidativo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
BMC Genomics ; 15: 534, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24972496

RESUMO

BACKGROUND: Developmental transcriptional regulatory networks are circuits of transcription factors (TFs) and cis-acting DNA elements (Cis Regulatory Modules, CRMs) that dynamically control expression of downstream genes. Comprehensive knowledge of these networks is an essential step towards our understanding of developmental processes. However, this knowledge is mostly based on genome-wide mapping of transcription factor binding sites, and therefore requires prior knowledge regarding the TFs involved in the network. RESULTS: Focusing on how temporal control of gene expression is integrated within a developmental network, we applied an in silico approach to discover regulatory motifs and CRMs of co-expressed genes, with no prior knowledge about the involved TFs. Our aim was to identify regulatory motifs and potential trans-acting factors which regulate the temporal expression of co-expressed gene sets during a particular process of organogenesis, namely adult heart formation in Drosophila. Starting from whole genome tissue specific expression dynamics, we used an in silico method, cisTargetX, to predict TF binding motifs and CRMs. Potential Nuclear Receptor (NR) binding motifs were predicted to control the temporal expression profile of a gene set with increased expression levels during mid metamorphosis. The predicted CRMs and NR motifs were validated in vivo by reporter gene essays. In addition, we provide evidence that three NRs modulate CRM activity and behave as temporal regulators of target enhancers. CONCLUSIONS: Our approach was successful in identifying CRMs and potential TFs acting on the temporal regulation of target genes. In addition, our results suggest a modular architecture of the regulatory machinery, in which the temporal and spatial regulation can be uncoupled and encoded by distinct CRMs.


Assuntos
Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Animais , Sequência de Bases , Simulação por Computador , Proteínas de Drosophila/biossíntese , Proteínas de Drosophila/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Elementos Facilitadores Genéticos , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Coração/fisiologia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Limite de Detecção , Metamorfose Biológica , Dados de Sequência Molecular , Curva ROC , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/fisiologia , Ativação Transcricional , Transcriptoma , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
12.
Proc Natl Acad Sci U S A ; 108(2): 834-9, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21187381

RESUMO

The neuromodulatory function of dopamine (DA) is an inherent feature of nervous systems of all animals. To learn more about the function of neural DA in Drosophila, we generated mutant flies that lack tyrosine hydroxylase, and thus DA biosynthesis, selectively in the nervous system. We found that DA is absent or below detection limits in the adult brain of these flies. Despite this, they have a lifespan similar to WT flies. These mutants show reduced activity, extended sleep time, locomotor deficits that increase with age, and they are hypophagic. Whereas odor and electrical shock avoidance are not affected, aversive olfactory learning is abolished. Instead, DA-deficient flies have an apparently "masochistic" tendency to prefer the shock-associated odor 2 h after conditioning. Similarly, sugar preference is absent, whereas sugar stimulation of foreleg taste neurons induces normal proboscis extension. Feeding the DA precursor L-DOPA to adults substantially rescues the learning deficit as well as other impaired behaviors that were tested. DA-deficient flies are also defective in positive phototaxis, without alteration in visual perception and optomotor response. Surprisingly, visual tracking is largely maintained, and these mutants still possess an efficient spatial orientation memory. Our findings show that flies can perform complex brain functions in the absence of neural DA, whereas specific behaviors involving, in particular, arousal and choice require normal levels of this neuromodulator.


Assuntos
Sistema Nervoso Central/fisiologia , Dopamina/deficiência , Drosophila/fisiologia , Animais , Comportamento Animal , Encéfalo/metabolismo , Dopamina/fisiologia , Mutação da Fase de Leitura , Homozigoto , Levodopa/química , Memória , Movimento , Neurotransmissores/metabolismo , Olfato , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/genética
13.
Oncol Rep ; 49(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37114528

RESUMO

Cervical cancer (CC) is a multifactorial disease of which human papillomavirus (HPV) is the main etiological agent. Despite cervical Pap smear screening and anti­HPV vaccination, CC remains a major public health issue. Identification of specific gene expression signatures in the blood could allow better insight into the immune response of CC and could provide valuable information for the development of novel biomarkers. The present study performed a transcriptomic analysis of peripheral blood mononuclear cells (PBMCs) from Senegalese patients with CC (n=31), low­grade cervical intraepithelial neoplasia (CIN1; n=27) and from healthy control (CTR) subjects (n=29). Individuals in the CIN1 and CTR groups exhibited similar patterns in gene expression. A total of 182 genes were revealed to be differentially expressed in patients with CC compared with individuals in the CIN1 and CTR groups. The IL1R2, IL18R1, MMP9 and FKBP5 genes were the most upregulated, whereas the T­cell receptor α gene TRA was the most downregulated in the CC group compared with in the CIN1 and CTR groups. The pathway enrichment analysis of the differentially expressed genes revealed pathways directly and indirectly linked to inflammation. To the best of our knowledge, the present study is the first large transcriptomic study on CC performed using PBMCs from African women; the results revealed the involvement of genes and pathways related to inflammation, most notably the IL­1 pathway, and the involvement of downregulation of the T­cell receptor α, a key component of the immune response. Several of the stated genes have already been reported in other cancer studies as putative blood biomarkers, thus reinforcing the requirement for deeper investigation. These findings may aid in the development of innovative clinical biomarkers for CC prevention and should be further replicated in other populations.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Leucócitos Mononucleares/patologia , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/diagnóstico , Perfilação da Expressão Gênica , Biomarcadores , Papillomaviridae/genética
14.
Elife ; 112022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383075

RESUMO

Deciphering the genetic architecture of human cardiac disorders is of fundamental importance but their underlying complexity is a major hurdle. We investigated the natural variation of cardiac performance in the sequenced inbred lines of the Drosophila Genetic Reference Panel (DGRP). Genome-wide associations studies (GWAS) identified genetic networks associated with natural variation of cardiac traits which were used to gain insights as to the molecular and cellular processes affected. Non-coding variants that we identified were used to map potential regulatory non-coding regions, which in turn were employed to predict transcription factors (TFs) binding sites. Cognate TFs, many of which themselves bear polymorphisms associated with variations of cardiac performance, were also validated by heart-specific knockdown. Additionally, we showed that the natural variations associated with variability in cardiac performance affect a set of genes overlapping those associated with average traits but through different variants in the same genes. Furthermore, we showed that phenotypic variability was also associated with natural variation of gene regulatory networks. More importantly, we documented correlations between genes associated with cardiac phenotypes in both flies and humans, which supports a conserved genetic architecture regulating adult cardiac function from arthropods to mammals. Specifically, roles for PAX9 and EGR2 in the regulation of the cardiac rhythm were established in both models, illustrating that the characteristics of natural variations in cardiac function identified in Drosophila can accelerate discovery in humans.


Assuntos
Drosophila melanogaster , Coração , Locos de Características Quantitativas , Animais , Humanos , Drosophila melanogaster/fisiologia , Redes Reguladoras de Genes , Variação Genética , Estudo de Associação Genômica Ampla , Fenótipo , Coração/fisiologia
15.
Front Immunol ; 12: 755862, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867992

RESUMO

Infection by the protozoan Trypanosoma cruzi causes Chagas disease cardiomyopathy (CCC) and can lead to arrhythmia, heart failure and death. Chagas disease affects 8 million people worldwide, and chronic production of the cytokines IFN-γ and TNF-α by T cells together with mitochondrial dysfunction are important players for the poor prognosis of the disease. Mitochondria occupy 40% of the cardiomyocytes volume and produce 95% of cellular ATP that sustain the life-long cycles of heart contraction. As IFN-γ and TNF-α have been described to affect mitochondrial function, we hypothesized that IFN-γ and TNF-α are involved in the myocardial mitochondrial dysfunction observed in CCC patients. In this study, we quantified markers of mitochondrial dysfunction and nitro-oxidative stress in CCC heart tissue and in IFN-γ/TNF-α-stimulated AC-16 human cardiomyocytes. We found that CCC myocardium displayed increased levels of nitro-oxidative stress and reduced mitochondrial DNA as compared with myocardial tissue from patients with dilated cardiomyopathy (DCM). IFN-γ/TNF-α treatment of AC-16 cardiomyocytes induced increased nitro-oxidative stress and decreased the mitochondrial membrane potential (ΔΨm). We found that the STAT1/NF-κB/NOS2 axis is involved in the IFN-γ/TNF-α-induced decrease of ΔΨm in AC-16 cardiomyocytes. Furthermore, treatment with mitochondria-sparing agonists of AMPK, NRF2 and SIRT1 rescues ΔΨm in IFN-γ/TNF-α-stimulated cells. Proteomic and gene expression analyses revealed that IFN-γ/TNF-α-treated cells corroborate mitochondrial dysfunction, transmembrane potential of mitochondria, altered fatty acid metabolism and cardiac necrosis/cell death. Functional assays conducted on Seahorse respirometer showed that cytokine-stimulated cells display decreased glycolytic and mitochondrial ATP production, dependency of fatty acid oxidation as well as increased proton leak and non-mitochondrial oxygen consumption. Together, our results suggest that IFN-γ and TNF-α cause direct damage to cardiomyocytes' mitochondria by promoting oxidative and nitrosative stress and impairing energy production pathways. We hypothesize that treatment with agonists of AMPK, NRF2 and SIRT1 might be an approach to ameliorate the progression of Chagas disease cardiomyopathy.


Assuntos
Cardiomiopatia Chagásica/metabolismo , Interferon gama/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Cardiomiopatia Chagásica/patologia , Cardiomiopatia Chagásica/fisiopatologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Miócitos Cardíacos/patologia , Adulto Jovem
16.
Plants (Basel) ; 9(9)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899727

RESUMO

Global change scenarios in the Mediterranean basin predict a precipitation reduction within the coming hundred years. Therefore, increased drought will affect forests both in terms of adaptive ecology and ecosystemic services. However, how vegetation might adapt to drought is poorly understood. In this report, four years of climate change was simulated by excluding 35% of precipitation above a downy oak forest. RNASeq data allowed us to assemble a genome-guided transcriptome. This led to the identification of differentially expressed features, which was supported by the characterization of target metabolites using a metabolomics approach. We provided 2.5 Tb of RNASeq data and the assembly of the first genome guided transcriptome of Quercus pubescens. Up to 5724 differentially expressed transcripts were obtained; 42 involved in plant response to drought. Transcript set enrichment analysis showed that drought induces an increase in oxidative pressure that is mitigated by the upregulation of ubiquitin-like protein protease, ferrochelatase, oxaloacetate decarboxylase and oxo-acid-lyase activities. Furthermore, the downregulation of auxin biosynthesis and transport, carbohydrate storage metabolism were observed as well as the concomitant accumulation of metabolites, such as oxalic acid, malate and isocitrate. Our data suggest that early metabolic changes in the resistance of Q. pubescens to drought involve a tricarboxylic acid (TCA) cycle shunt through the glyoxylate pathway, galactose metabolism by reducing carbohydrate storage and increased proteolytic activity.

17.
PLoS One ; 15(5): e0233191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453736

RESUMO

The Ikzf1 locus encodes the lymphoid specific transcription factor Ikaros, which plays an essential role in both T and B cell differentiation, while deregulation or mutation of IKZF1/Ikzf1 is involved in leukemia. Tissue-specific and cell identity genes are usually associated with clusters of enhancers, also called super-enhancers, which are believed to ensure proper regulation of gene expression throughout cell development and differentiation. Several potential regulatory regions have been identified in close proximity of Ikzf1, however, the full extent of the regulatory landscape of the Ikzf1 locus is not yet established. In this study, we combined epigenomics and transcription factor binding along with high-throughput enhancer assay and 4C-seq to prioritize an enhancer element located 120 kb upstream of the Ikzf1 gene. We found that deletion of the E120 enhancer resulted in a significant reduction of Ikzf1 mRNA. However, the epigenetic landscape and 3D topology of the locus were only slightly affected, highlighting the complexity of the regulatory landscape regulating the Ikzf1 locus.


Assuntos
Elementos Facilitadores Genéticos/fisiologia , Regulação da Expressão Gênica/fisiologia , Loci Gênicos/fisiologia , Fator de Transcrição Ikaros/biossíntese , Animais , Linhagem Celular , Epigenômica , Genes Reporter , Fator de Transcrição Ikaros/genética , Camundongos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
18.
Gynecol Oncol ; 115(3): 476-81, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19818481

RESUMO

OBJECTIVE: To evaluate whether prophylactic chemotherapy (P-chem) with one bolus dose of actinomycin D (Act-D) during the uterine evacuation of patients with high-risk hydatidiform mole (Hr-HM) affects reproductive outcomes in subsequent pregnancies. METHODS: From 1987 to 2006, 1090 patients with gestational trophoblastic disease (GTD) were evaluated at a Trophoblastic Disease Center in southern Brazil; 265 with Hr-HM were selected and retrospectively analyzed. From 1996 to 2006, 163 received one bolus dose of Act-D at the time of uterine evacuation (Hr-HM-chem group); 102 with the same risk factors did not get P-chem (Hr-HM-control group). In March 2009, the number of pregnancies, progression of first pregnancy, and association of low age and low parity with subsequent pregnancy were evaluated. RESULTS: The percentage of patients that became pregnant was similar in both groups (Hr-HM-control: 59.5%; Hr-HM-chem group: 45.7%; p=0.069) and independent of HM progression. Percentages of no pregnancies because of age (> or =40 years) or hysterectomy were also similar. Type of subsequent pregnancy was not statistically different between groups, and the rate of live births associated with pregnancies for which US showed a live fetus was high. Frequency of repeat GTD was unexpectedly high in both groups (4.2% and 6.3%; p=1.00). CONCLUSIONS: P-chem did not affect reproductive outcomes for patients with Hr-HM. Patients allowed to become pregnant again in both groups had high rates of live births associated with normal pregnancies. Chances of a subsequent pregnancy were higher in the low age and low parity subgroups.


Assuntos
Dactinomicina/administração & dosagem , Mola Hidatiforme/tratamento farmacológico , Mola Hidatiforme/cirurgia , Adulto , Terapia Combinada , Feminino , Humanos , Gravidez , Resultado da Gravidez , Reprodução , Adulto Jovem
19.
Intensive Care Med Exp ; 7(1): 50, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31428883

RESUMO

OBJECTIVES: The aims of this study are to better understand phenotypic differences between male and female rats during sepsis, to characterise the contribution of the beta1-adrenergic blocker landiolol to septic cardiomyopathy and to determine why landiolol induces divergent effects in males and females. METHODS: The myocardial transcriptional profiles in male and female Wistar rats were assessed after the induction of sepsis by cecal ligation and puncture and addition of landiolol. RESULTS: Our results showed major differences in the biological processes activated during sepsis in male and female rats. In particular, a significant decrease in processes related to cell organisation, contractile function, ionic transport and phosphoinositide-3-kinase/AKT (PI3K/AKT) signalling was observed only in males. The transcript of ATPase sarcoplasmic/endoplasmic reticulum Ca2+ transporting 3 (SERCA3) was sex-differently regulated. In males, landiolol reversed several signalling pathways dysregulated during sepsis. The expression level of genes encoding tubulin alpha 8 (TUBA8) and myosin heavy chain 7B (MYH7) contractile proteins, phosphatase 2 catalytic subunit alpha (PPP2CA), G protein-coupled receptor kinase 5 (GRK5) and A-kinase anchoring protein 6 (AKAP6) returned to their basal levels. In contrast, in females, landiolol had limited effects. CONCLUSION: In males, landiolol reversed the expression of many genes that were deregulated in sepsis. Conversely, sepsis-induced deregulation of gene expression was less pronounced in females than in males, and was maintained in the landiolol-treated females. These findings highlight important sex-related differences and confirm previous observations on the important benefit of landiolol intake on cardiac function in male rats.

20.
BMC Med Genomics ; 12(1): 148, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666081

RESUMO

BACKGROUND: Plasmodium falciparum malaria remains a major health problem in Africa. The mechanisms of pathogenesis are not fully understood. Transcriptomic studies may provide new insights into molecular pathways involved in the severe form of the disease. METHODS: Blood transcriptional levels were assessed in patients with cerebral malaria, non-cerebral malaria, or mild malaria by using microarray technology to look for gene expression profiles associated with clinical status. Multi-way ANOVA was used to extract differentially expressed genes. Network and pathways analyses were used to detect enrichment for biological pathways. RESULTS: We identified a set of 443 genes that were differentially expressed in the three patient groups after applying a false discovery rate of 10%. Since the cerebral patients displayed a particular transcriptional pattern, we focused our analysis on the differences between cerebral malaria patients and mild malaria patients. We further found 842 differentially expressed genes after applying a false discovery rate of 10%. Unsupervised hierarchical clustering of cerebral malaria-informative genes led to clustering of the cerebral malaria patients. The support vector machine method allowed us to correctly classify five out of six cerebral malaria patients and six of six mild malaria patients. Furthermore, the products of the differentially expressed genes were mapped onto a human protein-protein network. This led to the identification of the proteins with the highest number of interactions, including GSK3B, RELA, and APP. The enrichment analysis of the gene functional annotation indicates that genes involved in immune signalling pathways play a role in the occurrence of cerebral malaria. These include BCR-, TCR-, TLR-, cytokine-, FcεRI-, and FCGR- signalling pathways and natural killer cell cytotoxicity pathways, which are involved in the activation of immune cells. In addition, our results revealed an enrichment of genes involved in Alzheimer's disease. CONCLUSIONS: In the present study, we examine a set of genes whose expression differed in cerebral malaria patients and mild malaria patients. Moreover, our results provide new insights into the potential effect of the dysregulation of gene expression in immune pathways. Host genetic variation may partly explain such alteration of gene expression. Further studies are required to investigate this in African populations.


Assuntos
Malária Cerebral/patologia , Transcriptoma/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Lactente , Malária Cerebral/sangue , Malária Cerebral/genética , Masculino , Pessoa de Meia-Idade , Mapas de Interação de Proteínas/genética , Senegal , Índice de Gravidade de Doença , Transdução de Sinais , Fator de Transcrição RelA/genética , Adulto Jovem
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