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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38711368

RESUMO

Common genetic variants and susceptibility loci associated with Alzheimer's disease (AD) have been discovered through large-scale genome-wide association studies (GWAS), GWAS by proxy (GWAX) and meta-analysis of GWAS and GWAX (GWAS+GWAX). However, due to the very low repeatability of AD susceptibility loci and the low heritability of AD, these AD genetic findings have been questioned. We summarize AD genetic findings from the past 10 years and provide a new interpretation of these findings in the context of statistical heterogeneity. We discovered that only 17% of AD risk loci demonstrated reproducibility with a genome-wide significance of P < 5.00E-08 across all AD GWAS and GWAS+GWAX datasets. We highlighted that the AD GWAS+GWAX with the largest sample size failed to identify the most significant signals, the maximum number of genome-wide significant genetic variants or maximum heritability. Additionally, we identified widespread statistical heterogeneity in AD GWAS+GWAX datasets, but not in AD GWAS datasets. We consider that statistical heterogeneity may have attenuated the statistical power in AD GWAS+GWAX and may contribute to explaining the low repeatability (17%) of genome-wide significant AD susceptibility loci and the decreased AD heritability (40-2%) as the sample size increased. Importantly, evidence supports the idea that a decrease in statistical heterogeneity facilitates the identification of genome-wide significant genetic loci and contributes to an increase in AD heritability. Collectively, current AD GWAX and GWAS+GWAX findings should be meticulously assessed and warrant additional investigation, and AD GWAS+GWAX should employ multiple meta-analysis methods, such as random-effects inverse variance-weighted meta-analysis, which is designed specifically for statistical heterogeneity.


Assuntos
Doença de Alzheimer , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Doença de Alzheimer/genética , Humanos , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único , Heterogeneidade Genética
2.
Neurobiol Dis ; 177: 105983, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586468

RESUMO

Nucleus basalis of Meynert (NbM), one of the earliest targets of Alzheimer's disease (AD), may act as a seed for pathological spreading to its connected regions. However, the underlying basis of regional vulnerability to NbM dysconnectivity remains unclear. NbM functional dysconnectivity was assessed using resting-state fMRI data of health controls and mild cognitive impairment (MCI) patients from the Alzheimer's disease Neuroimaging Initiative (ADNI2/GO phase). Transcriptional correlates of NbM dysconnectivity was explored by leveraging public intrinsic and differential post-mortem brain-wide gene expression datasets from Allen Human Brain Atlas (AHBA) and Mount Sinai Brain Bank (MSBB). By constructing an individual-level tissue-specific gene set risk score (TGRS), we evaluated the contribution of NbM dysconnectivity-correlated gene sets to change rate of cerebral spinal fluid (CSF) biomarkers during preclinical stage of AD, as well as to MCI onset age. An independent cohort of health controls and MCI patients from ADNI3 was used to validate our main findings. Between-group comparison revealed significant connectivity reduction between the right NbM and right middle temporal gyrus in MCI. This regional vulnerability to NbM dysconnectivity correlated with intrinsic expression of genes enriched in protein and immune functions, as well as with differential expression of genes enriched in cholinergic receptors, immune, vascular and energy metabolism functions. TGRS of these NbM dysconnectivity-correlated gene sets are associated with longitudinal amyloid-beta change at preclinical stages of AD, and contributed to MCI onset age independent of traditional AD risks. Our findings revealed the transcriptional vulnerability to NbM dysconnectivity and their crucial role in explaining preclinical amyloid-beta change and MCI onset age, which offer new insights into the early AD pathology and encourage more investigation and clinical trials targeting NbM.


Assuntos
Doença de Alzheimer , Prosencéfalo Basal , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Prosencéfalo Basal/patologia , Núcleo Basal de Meynert/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Peptídeos beta-Amiloides/metabolismo
3.
J Med Virol ; 95(5): e28780, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37212302

RESUMO

Observational studies have shown that vitamin D supplementation reduces the risk of COVID-19 infection, yet little is known about the shared genomic architectures between them. Leveraging large-scale genome-wide association study (GWAS) summary statistics, we investigated the genetic correlation and causal relationship between genetically determined vitamin D and COVID-19 using linkage disequilibrium score regression and Mendelian randomization (MR) analyses, and conducted a cross-trait GWAS meta-analysis to identify the overlapping susceptibility loci of them. We observed a significant genetic correlation between genetically predicted vitamin D and COVID-19 (rg = -0.143, p = 0.011), and the risk of COVID-19 infection would decrease by 6% for every 0.76 nmol L-1 increase of serum 25 hydroxyvitamin D (25OHD) concentrations in generalized MR (OR = 0.94, 95% CI: 0.89-0.99, p = 0.019). We identified rs4971066 (EFNA1) as a risk locus for the joint phenotype of vitamin D and COVID-19. In conclusion, genetically determined vitamin D is associated with COVID-19. Increased levels of serum 25OHD concentration may benefit the prevention and treatment of COVID-19.


Assuntos
COVID-19 , Estudo de Associação Genômica Ampla , Humanos , COVID-19/epidemiologia , Vitamina D , Vitaminas , Fenótipo , Polimorfismo de Nucleotídeo Único
4.
Mol Psychiatry ; 27(10): 4297-4306, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35840796

RESUMO

Mendelian-randomization (MR) studies using large-scale genome-wide association studies (GWAS) have identified causal association between educational attainment and Alzheimer's disease (AD). However, the underlying mechanisms are still required to be explored. Here, we conduct univariable and multivariable MR analyses using large-scale educational attainment, cognitive performance, intelligence and AD GWAS datasets. In stage 1, we found significant causal effects of educational attainment on cognitive performance (beta = 0.907, 95% confidence interval (CI): 0.884-0.930, P < 1.145E-299), and vice versa (beta = 0.571, 95% CI: 0.557-0.585, P < 1.145E-299). In stage 2, we found that both increase in educational attainment (odds ratio (OR) = 0.72, 95% CI: 0.66-0.78, P = 1.39E-14) and cognitive performance (OR = 0.69, 95% CI: 0.64-0.75, P = 1.78E-20) could reduce the risk of AD. In stage 3, we found that educational attainment may protect against AD dependently of cognitive performance (OR = 1.07, 95% CI: 0.90-1.28, P = 4.48E-01), and cognitive performance may protect against AD independently of educational attainment (OR = 0.69, 95% CI: 0.53-0.89, P = 5.00E-03). In stage 4, we found significant causal effects of cognitive performance on intelligence (beta = 0.907, 95% CI: 0.877-0.938, P < 1.145E-299), and vice versa (beta = 0.957, 95% CI: 0.937-0.978, P < 1.145E-299). In stage 5, we identified that cognitive performance may protect against AD independently of intelligence (OR = 0.74, 95% CI: 0.61-0.90, P = 2.00E-03), and intelligence may protect against AD dependently of cognitive performance (OR = 1.17, 95% CI: 0.40-3.43, P = 4.48E-01). Collectively, our univariable and multivariable MR analyses highlight the protective role of cognitive performance in AD independently of educational attainment and intelligence. In addition to the intelligence, we extend the mechanisms underlying the associations of educational attainment with AD.


Assuntos
Doença de Alzheimer , Estudo de Associação Genômica Ampla , Humanos , Doença de Alzheimer/genética , Polimorfismo de Nucleotídeo Único , Inteligência , Escolaridade , Cognição
5.
Cerebrovasc Dis ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38113871

RESUMO

Background The relationship between ischemic stroke (IS) and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity is still unclear, and there is a dearth of stratified research on the relationship between Lp-PLA2 activity and different IS subtypes. Therefore, Mendelian randomization was used in this study to examine the relationship between genetically proxied Lp-PLA2 activity and the risks of IS and its subtypes. Methods Based on information from a meta-analysis of GWAS, which included 13,664 European people, five single-nucleotide polymorphisms related to Lp-PLA2 activity were chosen as instrumental variables. Summary statistics information about MEGESTROKE consortium with the European group (40,585 cases and 406,111 controls) include any ischemic stroke (AIS) (n = 34,217); large-artery stroke (LAS, n=4,373), cardioembolic stroke (CES, n=7,193) and small vessel stroke (SVS, n=5,386). In order to determine the causal relationships between Lp-PLA2 activity and IS as well as its subtypes, the inverse variance weighted (IVW) approach was chosen as the primary analysis. Significant estimates were then tested by sensitivity analysis to rule out heterogeneity and pleiotropy. Results IVW showed Lp-PLA2 activity was causally associated with LAS (OR=3.25, 95% CI=1.65-6.41, p=0.0007), but not with other subtypes of stroke. Sensitivity analysis for causal estimates between Lp-PLA2 activity and LAS showed no significant heterogeneity or pleiotropy. Conclusions These MR analyses support a causal effect of Lp-PLA2 activity on LAS but not on AIS, CES or SVS, which suggests that serum Lp-PLA2 activity might be a biomarker for prediction of LAS.

6.
Molecules ; 27(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35630823

RESUMO

Anthracycline dutomycin is a tetracyclic quinone glycoside produced by Streptomyces minoensis NRRL B-5482. SW91 is a C-12 demethylated dutomycin derivative, which was identified in our previous research. In vitro cytotoxicity and apoptosis assays of these two compounds were conducted to demonstrate their antiproliferation activities. The results showed that both dutomycin and SW91 block cells at the S phase, whereas dutomycin shows more significant inhibition of cell growth. Their interactions with calf thymus DNA (CT-DNA) were investigated, with dutomycin exhibiting higher binding affinity. The molecular docking demonstrated that the 12-methyl group makes dutomycin attach to the groove of DNA. These findings suggest that dutomycin has binding higher affinity to DNA and impairs DNA replication resulting in more significant antitumor activity.


Assuntos
Antraciclinas , Policetídeos , Antraciclinas/farmacologia , Antibióticos Antineoplásicos/farmacologia , DNA/química , Simulação de Acoplamento Molecular
7.
BMC Med ; 19(1): 11, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33461566

RESUMO

BACKGROUND: It has been well established that the TMEM106B gene rs1990622 variant was a frontotemporal dementia (FTD) risk factor. Until recently, growing evidence highlights the role of TMEM106B in Alzheimer's disease (AD). However, it remains largely unclear about the role of rs1990622 variant in AD. METHODS: Here, we conducted comprehensive analyses including genetic association study, gene expression analysis, eQTLs analysis, and colocalization analysis. In stage 1, we conducted a genetic association analysis of rs1990622 using large-scale genome-wide association study (GWAS) datasets from International Genomics of Alzheimer's Project (21,982 AD and 41,944 cognitively normal controls) and UK Biobank (314,278 participants). In stage 2, we performed a gene expression analysis of TMEM106B in 49 different human tissues using the gene expression data in GTEx. In stage 3, we performed an expression quantitative trait loci (eQTLs) analysis using multiple datasets from UKBEC, GTEx, and Mayo RNAseq Study. In stage 4, we performed a colocalization analysis to provide evidence of the AD GWAS and eQTLs pair influencing both AD and the TMEM106B expression at a particular region. RESULTS: We found (1) rs1990622 variant T allele contributed to AD risk. A sex-specific analysis in UK Biobank further indicated that rs1990622 T allele only contributed to increased AD risk in females, but not in males; (2) TMEM106B showed different expression in different human brain tissues especially high expression in cerebellum; (3) rs1990622 variant could regulate the expression of TMEM106B in human brain tissues, which vary considerably in different disease statuses, the mean ages at death, the percents of females, and the different descents of the selected donors; (4) colocalization analysis provided suggestive evidence that the same variant contributed to AD risk and TMEM106B expression in cerebellum. CONCLUSION: Our comprehensive analyses highlighted the role of FTD rs1990622 variant in AD risk. This cross-disease approach may delineate disease-specific and common features, which will be important for both diagnostic and therapeutic development purposes. Meanwhile, these findings highlight the importance to better understand TMEM106B function and dysfunction in the context of normal aging and neurodegenerative diseases.


Assuntos
Doença de Alzheimer/genética , Encéfalo/metabolismo , Variação Genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Alelos , Doença de Alzheimer/metabolismo , Cognição , Feminino , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores Sexuais
8.
J Transl Med ; 19(1): 221, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030714

RESUMO

BACKGROUND: Until now, epidemiological evidence regarding the association between vitamin C intake (both diet and supplements) and Parkinson's disease (PD) remains inconsistent. Hence, it is necessary to establish the causal link between vitamin C levels and PD, and further develop effective therapies or prevention. METHODS: We selected 11 newly identified plasma vitamin C genetic variants from a large-scale plasma vitamin C GWAS dataset (n = 52,018) as the effective instrumental variables, and extracted their corresponding GWAS summary statistics from PD (33,674 PD cases and 449,056 controls) and PD age at onset (AAO) (n = 28,568). We then performed a Mendelian randomization (MR) study to evaluate the causal association of plasma vitamin C levels with PD and PD AAO using inverse-variance weighted (IVW), the weighted median, MR-Egger, and MR-PRESSO test. RESULTS: We did not observe any significant association between genetically increased vitamin C levels and PD. Interestingly, we found a reduced trend of PD AAO (1.134 years) with 1 SD genetically increased vitamin C levels using IVW (beta = - 1.134, 95% CI: [- 2.515, 0.248], P = 0.108). Importantly, this trend was further successfully verified using both weighted median and MR-Egger. Each 1 SD genetically increased vitamin C levels could reduce PD AAO 1.75 and 2.592 years using weighted median (beta = - 1.750, 95% CI: [- 3.396, - 0.105], P = 0.037) and MR-Egger (beta = - 2.592, 95% CI: [- 4.623, - 0.560], P = 0.012). CONCLUSIONS: We demonstrated the causal association between genetically increased plasma vitamin C levels and reduced PD AAO in people of European descent. Randomized controlled trials are required to clarify whether diet intake or supplement, or both could reduce the AAO of PD.


Assuntos
Análise da Randomização Mendeliana , Doença de Parkinson , Idade de Início , Ácido Ascórbico , Estudo de Associação Genômica Ampla , Humanos , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética
9.
FASEB J ; 34(8): 10107-10116, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32725952

RESUMO

The rs6647 variant G allele in SERPINA1 gene was reported to be associated with the risk of large artery atherosclerotic stroke (LAS), however, the mechanism remains unclear. Here, we performed a functional annotation of the rs6647 variant by using the software HaploReg version 4.1 (HaploReg v4.1). Next, the expression quantitative trait loci (eQTLs) analysis of multiple datasets was conducted for determining the association between the rs6647 and SERPINA1 expression in various tissues. Then, a case-control gene expression analysis was done using two independent ischemic stroke (IS) gene expression datasets. Finally, SERPINA1 expression in whole blood samples from 8 LAS patients and 14 healthy persons were compared. The functional annotation suggested that the rs6647 regulates gene expression in multiple human tissues especially in brain and blood. The eQTLs analysis revealed a significant association of the rs6647 G allele with increased expression of SERPINA1 gene only in whole blood. Compared with the controls, there was an increased expression of SERPINA1 gene in whole blood in both IS patients and LAS patients. SERPINA1 gene expression in whole blood bridges the rs6647 variant G allele with increased LAS risk, providing new insights into the mechanisms underlying role of the rs6647 in determining LAS risk.


Assuntos
Aterosclerose/genética , Expressão Gênica/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , alfa 1-Antitripsina/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica/métodos , Genótipo , Humanos , Masculino , Locos de Características Quantitativas/genética
10.
Nucleic Acids Res ; 47(D1): D140-D144, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30380072

RESUMO

Long non-coding RNAs (lncRNAs) play crucial roles in regulating gene expression, and a growing number of researchers have focused on the identification of target genes of lncRNAs. However, no online repository is available to collect the information on target genes regulated by lncRNAs. To make it convenient for researchers to know what genes are regulated by a lncRNA of interest, we developed a database named lncRNA2Target to provide a comprehensive resource of lncRNA target genes in 2015. To update the database this year, we retrieved all new lncRNA-target relationships from papers published from 1 August 2014 to 30 April 2018 and RNA-seq datasets before and after knockdown or overexpression of a specific lncRNA. LncRNA2Target database v2.0 provides a web interface through which its users can search for the targets of a particular lncRNA or for the lncRNAs that target a particular gene, and is freely accessible at http://123.59.132.21/lncrna2target.


Assuntos
Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Regulação da Expressão Gênica , Interferência de RNA , RNA Longo não Codificante/genética , Animais , Humanos , Camundongos , Software , Interface Usuário-Computador , Navegador
11.
Brief Bioinform ; 19(1): 89-100, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27760738

RESUMO

At present, understanding of DNA methylation at the population level is still limited. Here, we first extended the classical framework of population genetics, such as single nucleotide polymorphism allele frequency, linkage disequilibrium (LD), LD block and haplotype, to epigenetics. Then, as an example, we compared the DNA methylation disequilibrium (MD) maps between HapMap CEU (Caucasian residents of European ancestry from Utah) population and YRI (Yoruba people from Ibadan) population (lymphoblastoid cell lines). We analyzed the differences and similarities between CEU and YRI from the following aspects: SMP (single methylation polymorphism) allele frequency, SMP allele association, MD, MD block and methylation haplotype (meplotype) frequency. The results showed that CEU and YRI had similar distribution of SMP allele frequency, and shared many MD block region. We believe that the framework of population genetics can be used in the population epigenetics. The population epigenetic framework also has potential prospects in the study of complex diseases, such as epigenome-wide association study.


Assuntos
População Negra/genética , Epigênese Genética , Genética Populacional/métodos , Polimorfismo de Nucleotídeo Único , População Branca/genética , Alelos , Células Cultivadas , Metilação de DNA , Projeto HapMap , Haplótipos , Humanos , Desequilíbrio de Ligação , Linfócitos/citologia , Linfócitos/metabolismo
13.
J Immunol ; 200(5): 1618-1626, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29378913

RESUMO

Inflammation that complicates many autoimmune diseases, such as multiple sclerosis (MS), has been correlated to abnormal differentiation of Th17 cells. However, the reasons that promote Th17 cell-driven autoimmunity are yet to be discovered. In this study, we sought evidence that DNA-damage-inducible transcript 4 (DDIT4) and its associated long noncoding RNA DDIT4 (lncDDIT4) inhibit Th17 cell differentiation. We recruited 36 patients. Six MS patients and five healthy volunteers (controls) contributed PBMCs as material for microarray analysis. Microarray assays of lncDDIT4 and DDIT4 RNA expression identified outstanding differences between MS and control subjects, which were verified with real-time quantitative PCR. We then interrupted the expression of lncDDIT4 and DDIT4 mRNA in MS patients' naive CD4+ T cells and observed the resulting changes in Th17 cells. The expression of lncDDIT4 and DDIT4 mRNA were higher both in PBMCs and CD4+ T cells of MS patients than in healthy controls. DDIT4 (2.79-fold upregulation) was then recognized as a candidate for the cis-regulated target of lncDDIT4 (4.32-fold upregulation). Isolation of naive CD4+ T cells revealed enhanced levels of lncDDIT4 and DDIT4 after stimulated with Th17-inducing cytokines, but not after Th1, Th2, or T regulatory cell induction. Overexpression of lncDDIT4 in naive CD4+ T cells inhibited IL-17 transcription through increased DDIT4 expression and decreased activation of the DDIT4/mTOR pathway. Consistently, silencing lncDDIT4 in naive CD4+ T cells enhanced Th17 differentiation through increased activation of the DDIT4/mTOR pathway. However, these results vanished when DDIT4 was silenced. This outcome suggests that lncDDIT4 regulates Th17 cell differentiation by directly targeting DDIT4.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/fisiologia , RNA Longo não Codificante/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Células Th17/metabolismo , Fatores de Transcrição/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo , Humanos , RNA Mensageiro/metabolismo , Linfócitos T Reguladores/metabolismo , Células Th2/metabolismo , Regulação para Cima/fisiologia
14.
Neurol Sci ; 41(10): 2875-2882, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32328834

RESUMO

BACKGROUND: Multiple sclerosis (MS) is a complex neurological disease and chronic inflammatory disease. Until now, observational studies have reported positive association between serum interleukin-6 (IL-6) levels and MS risk. In order to develop effective therapies, we should establish the causal link between IL-6 signaling and MS. However, it is currently unknown whether IL-6 signaling is causally associated with the risk of MS. METHODS: Here, we selected the increased soluble IL-6R (s-IL-6R) levels as the indirect markers for reduced IL-6 signaling, and performed a Mendelian randomization (MR) study using the rs2228145 variant as the instrumental variable to evaluate and quantify the effect of IL-6 signaling on the risk of MS. To be a comparison, we also evaluated the causal association of IL-6 signaling with the risk of other three neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). RESULTS: We found that the increased s-IL-6R levels (per 1 standard deviation) were significantly associated with decreased MS risk (OR = 0.96, 95% CI 0.94-0.98, P = 1.69E-04), but not associated with the risk of AD (OR = 1.01, 95% CI 0.92-1.11, P = 0.835), PD (OR = 0.94, 95% CI 0.84-1.05, P = 0.261), or ALS (OR = 1.00, 95% CI 0.92-1.10, P = 0.9411). CONCLUSION: Our findings have the similar directional effects to an existing humanized anti-IL-6R monoclonal antibody Tocilizumab which could bind to the IL-6 binding site of human IL-6R and competitively inhibit IL-6 signaling. Hence, we provided genetic evidence that inhibiting the IL-6 signaling such as tocilizumab treatment might represent a novel therapy for MS.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/genética , Humanos , Interleucina-6/genética , Análise da Randomização Mendeliana , Doenças Neurodegenerativas/genética , Transdução de Sinais
16.
Brief Bioinform ; 18(4): 712-721, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27373733

RESUMO

Gametogenesis is a complex process, which includes mitosis and meiosis and results in the production of ovum and sperm. The development of gametogenesis is dynamic and needs many different genes to work synergistically, but it is lack of global perspective research about this process. In this study, we detected the dynamic process of gametogenesis from the perspective of systems biology based on protein-protein interaction networks (PPINs) and functional analysis. Results showed that gametogenesis genes have strong synergistic effects in PPINs within and between different phases during the development. Addition to the synergistic effects on molecular networks, gametogenesis genes showed functional consistency within and between different phases, which provides the further evidence about the dynamic process during the development of gametogenesis. At last, we detected and provided the core molecular modules of different phases about gametogenesis. The gametogenesis genes and related modules can be obtained from our Web site Gametogenesis Molecule Online (GMO, http://gametsonline.nwsuaflmz.com/index.php), which is freely accessible. GMO may be helpful for the reference and application of these genes and modules in the future identification of key genes about gametogenesis. Summary, this work provided a computational perspective and frame to the analysis of the gametogenesis dynamics and modularity in both human and mouse.


Assuntos
Gametogênese , Redes Reguladoras de Genes , Animais , Humanos , Meiose , Camundongos , Mapas de Interação de Proteínas , Biologia de Sistemas
17.
Bioinformatics ; 34(15): 2657-2658, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29566144

RESUMO

Motivation: With the development of biotechnology, DNA methylation data showed exponential growth. Epigenome-wide association study (EWAS) provide a systematic approach to uncovering epigenetic variants underlying common diseases/phenotypes. But the EWAS software has lagged behind compared with genome-wide association study (GWAS). To meet the requirements of users, we developed a convenient and useful software, EWAS2.0. Results: EWAS2.0 can analyze EWAS data and identify the association between epigenetic variations and disease/phenotype. On the basis of EWAS1.0, we have added more distinctive features. EWAS2.0 software was developed based on our 'population epigenetic framework' and can perform: (i) epigenome-wide single marker association study; (ii) epigenome-wide methylation haplotype (meplotype) association study and (iii) epigenome-wide association meta-analysis. Users can use EWAS2.0 to execute chi-square test, t-test, linear regression analysis, logistic regression analysis, identify the association between epi-alleles, identify the methylation disequilibrium (MD) blocks, calculate the MD coefficient, the frequency of meplotype and Pearson's correlation coefficients and carry out meta-analysis and so on. Finally, we expect EWAS2.0 to become a popular software and be widely used in epigenome-wide associated studies in the future. Availability and implementation: The EWAS software is freely available at http://www.ewas.org.cn or http://www.bioapp.org/ewas.


Assuntos
Metilação de DNA , Epigenômica/métodos , Estudo de Associação Genômica Ampla/métodos , Software , Epigênese Genética , Fenótipo
18.
Metab Eng ; 54: 212-221, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31028901

RESUMO

The anthraquinones endocrocin and emodin are synthesized by a special class of type I NR-PKSs and a discrete MßL-TE. In this work, we first reconstituted a biosynthetic pathway of endocrocin and emodin in S. cerevisiae by combining enzymes from different sources. We functionally characterized a TE-less NR-PKS (SlACAS) and a MßL-TE (SlTE) from S. lycopersici as well as four orthologous MßL-TEs. SlACAS was coexpressed with different MßL-TEs in S. cerevisiae. SlACAS generated the highest amount of endocrocin when coupled with HyTE, the yield was 115.6% higher than that with the native SlTE. To accumulate more emodin, seven decarboxylases with high homology to HyDC were identified and introduced into the biosynthetic pathway. Among these orthologs, AfDC exhibited the highest catalytic activity and the conversion rate reached 98.6%. A double-point mutant acetyl-CoA carboxylase, ACC1S659A, S1157A, was further introduced to increase the production of malonyl-CoA as a precursor of these anthraquinones. The production of endocrocin (233.6 ±â€¯20.3 mg/L) and emodin (253.2 ±â€¯21.7 mg/L) then dramatically increased. We also optimized the carbon source in the medium and conducted fed-batch fermentation with the engineered strains. The titers of endocrocin and emodin obtained were 661.2 ±â€¯50.5 mg/L and 528.4 ±â€¯62.7 mg/L, respectively, which are higher than previously reported. In this work, by screening a small library of orthologous biosynthetic bricks, an efficient biosynthetic pathway of endocrocin and emodin was first created in S. cerevisiae. This study provides a novel metabolic engineering approach for optimization of the production of desired molecules.


Assuntos
Emodina/metabolismo , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Saccharomyces cerevisiae , Antracenos/metabolismo , Técnicas de Cultura Celular por Lotes , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
19.
J Cell Biochem ; 119(9): 7490-7497, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29797594

RESUMO

Over the past decades, the epidemic of childhood obesity has greatly increased, and it has recently become a global public health concern. Methylation, serving as a crucial regulator of the gene-environment interaction, has exhibited a strong association with obesity. In this study, we aimed to evaluate the relationship between DNA methylation and childhood obesity, and further uncover the potential association of aberrantly methylated genes with obesity. DNA samples of peripheral blood leukocytes from three obese subjects (mean BMI: 21.67) and 4 age/sex matched controls (mean BMI: 14.92) were subjected to Infinium Human Methylation 450 Bead Array analysis. A total of more than 4 85 000 methylation sites were identified across the genome, and 226 methylated CpGs (DMCpGs) were differentially methylated between these two groups. Subsequent Gene Ontology (GO) and KEGG Pathway analyses showed that these DMCpGs were mainly engaged in immunity and lipoprotein metabolism, indicating their physiological significance. Further verification of the candidate CpG sites within the HDAC4, RAX2, APOA5, CES1, and SLC25A20 gene loci, were performed using bisulfite sequencing PCR (BSP) in a cohort of 42 controls and 39 obese cases. The results revealed that methylation levels within HDAC4 and RAX2 loci were positively associated with obesity, while the methylation levels of loci within APOA5 and CES1 loci were negatively correlated with obesity. Thus, alterations in methylation of CpG sites of specific genes may contribute to childhood obesity, which provide novel insights into the aetiology of obesity.


Assuntos
Apolipoproteína A-V/genética , Hidrolases de Éster Carboxílico/genética , Metilação de DNA , Predisposição Genética para Doença , Histona Desacetilases/genética , Obesidade/genética , Proteínas Repressoras/genética , Criança , Pré-Escolar , Ilhas de CpG , Epigênese Genética , Feminino , Humanos , Metabolismo dos Lipídeos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos
20.
FASEB J ; 31(2): 519-525, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27756768

RESUMO

In this study, we strove to substantiate the ability of linc-MAF-4 to act as a regulator of pathogenesis during multiple sclerosis (MS). We recruited 34 patients who were diagnosed with MS according to the revised McDonald criteria. Six patients with MS and 5 healthy volunteers contributed peripheral blood mononuclear cells for microarray analysis. Subsequent knockdown and overexpression of linc-MAF-4 in naive CD4+ T cells from the additional 28 patients with MS was performed to track changes in CD4+ T-cell subsets and their function, as well as to confirm results from the prior microarray analysis. Expression of linc-MAF-4 increased significantly in peripheral blood mononuclear cells of patients with MS compared with those of control participants. In addition, linc-MAF-4 regulated encephalitogenic T helper (Th)1-cell differentiation in patients with MS. Transfection of synthetic linc-MAF-4 into naive CD4+ T cells facilitated Th1-cell differentiation and inhibited Th2-cell differentiation by directly inhibiting MAF, which is a Th2-cell transcription factor. Linc-MAF-4 also promoted activation of CD4+ T cells from patients with MS. Expression level of linc-MAF-4 correlated with the annual relapse rate in patients with MS. Our results suggest that linc-MAF-4 is involved in the pathogenesis of MS, specifically via regulation of encephalitogenic T cells.-Zhang, F., Liu, G., Wei, C., Gao, C., Hao, J. Linc-MAF-4 regulates Th1/Th2 differentiation and is associated with the pathogenesis of multiple sclerosis by targeting MAF.


Assuntos
Regulação da Expressão Gênica/fisiologia , Esclerose Múltipla/metabolismo , RNA Longo não Codificante/metabolismo , Células Th1/fisiologia , Células Th2/fisiologia , Adolescente , Adulto , Regulação para Baixo/fisiologia , Feminino , Humanos , Elementos Nucleotídeos Longos e Dispersos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Longo não Codificante/genética , Regulação para Cima , Adulto Jovem
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