Enhancer

增强子
  • 文章类型: Journal Article
    雄红蛋白(ADGB),哺乳动物珠蛋白家族的最新成员,是一种嵌合蛋白,嵌入的珠蛋白域,进行循环置换,并表现出六配位血红素结合方案的标志。尽管最初发现ADGB的大量表达主要限于精子发生减数分裂后阶段的细胞,最近的基于RNA-Seq的表达分析数据显示,ADGB可在携带活动纤毛或鞭毛的细胞中检测到。这种对ADGB基因表达的非常严格的调控促使需要替代技术来研究经典哺乳动物细胞模型中的内源性表达。不表示ADGB。我们在这里描述了使用CRISPR激活(CRISPRa)技术在HEK293T中诱导内源性ADGB基因表达,MCF-7和HeLa细胞从其启动子,并说明如何使用该方法来验证启动子和增强子区域中ADGB的推定调节DNA元件。
    Androglobin (ADGB), the most recently identified member of the mammalian globin family, is a chimeric protein with an unusual, embedded globin domain that is circularly permutated and exhibits hallmarks of a hexacoordinated heme-binding scheme. Whereas abundant expression of ADGB was initially found to be mainly restricted to cells in the postmeiotic stages of spermatogenesis, more recent RNA-Seq-based expression analysis data revealed that ADGB is detectable in cells carrying motile cilia or flagella. This very tight regulation of ADGB gene expression urges the need for alternative techniques to study endogenous expression in classical mammalian cell models, which do not express ADGB. We describe here the use of CRISPR activation (CRISPRa) technology to induce endogenous ADGB gene expression in HEK293T, MCF-7, and HeLa cells from its promoter and illustrate how this method can be employed to validate putative regulatory DNA elements of ADGB in promoter and enhancer regions.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    从一个发育阶段到另一个发育阶段的过渡伴随着发育程序和相应基因集合的激活。相应基因座的空间构象的变化与这种激活有关,并且可以在染色体构象捕获(3C)方法的帮助下进行研究。将3C应用于特定的发育阶段是一项复杂的任务。这里,我们描述了使用3C方法研究果蝇幼虫发育基因座的空间组织。我们严格地分析了现有的协议,并提供了我们自己的解决方案和优化的协议来克服局限性。为了证明我们手术的效率,我们研究了3龄果蝇幼虫发育位点Dad的空间组织。在胚胎细胞和活的野生型幼虫之间发现了基因座构象的差异。我们还观察到在幼虫中激活其表达后,在相邻转基因存在下建立了新的调节相互作用。我们的工作填补了将3C方法应用于果蝇幼虫的空白,并为在动物模型上建立3C提供了有用的指导。
    A transition from one developmental stage to another is accompanied by activation of developmental programs and corresponding gene ensembles. Changes in the spatial conformation of the corresponding loci are associated with this activation and can be investigated with the help of the Chromosome Conformation Capture (3C) methodology. Application of 3C to specific developmental stages is a sophisticated task. Here, we describe the use of the 3C method to study the spatial organization of developmental loci in Drosophila larvae. We critically analyzed the existing protocols and offered our own solutions and the optimized protocol to overcome limitations. To demonstrate the efficiency of our procedure, we studied the spatial organization of the developmental locus Dad in 3rd instar Drosophila larvae. Differences in locus conformation were found between embryonic cells and living wild-type larvae. We also observed the establishment of novel regulatory interactions in the presence of an adjacent transgene upon activation of its expression in larvae. Our work fills the gap in the application of the 3C method to Drosophila larvae and provides a useful guide for establishing 3C on an animal model.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    背景:FOXG1基因在哺乳动物的脑分化和发育中起着至关重要的作用。导致功能丧失或FOXG1基因表达改变的基因内和基因间突变引起FOXG1综合征。这种综合征的特征是严重的发育迟缓,缺乏口头语言,产后生长受限,产后小头畸形,以及以舞蹈症和肌张力障碍为特征的可识别的运动障碍。
    方法:在这里,我们描述了一例7岁男性患者,该患者通过G带染色体和荧光原位杂交(FISH)分析,发现3号染色体3q14.1带和14号染色体14q12带之间存在从头平衡易位。这种重排破坏了FOXG1与先前描述的最小缺失重叠区(SRO)的接近度,可能导致单倍体不足。
    结论:该病例增加了越来越多的文献,表明染色体结构变异与该疾病的表现有关,并强调了顺式调节元件在该基因正常表达中的重要作用。最后,我们提出了反射FISH分析方案,以提高疑似FOXG1综合征患者的诊断效率.
    BACKGROUND: The FOXG1 gene plays a vital role in mammalian brain differentiation and development. Intra- and intergenic mutations resulting in loss of function or altered expression of the FOXG1 gene cause FOXG1 syndrome. The hallmarks of this syndrome are severe developmental delay with absent verbal language, post-natal growth restriction, post-natal microcephaly, and a recognizable movement disorder characterized by chorea and dystonia.
    METHODS: Here we describe a case of a 7-year-old male patient found to have a de novo balanced translocation between chromosome 3 at band 3q14.1 and chromosome 14 at band 14q12 via G-banding chromosome and Fluorescence In Situ Hybridization (FISH) analyses. This rearrangement disrupts the proximity of FOXG1 to a previously described smallest region of deletion overlap (SRO), likely resulting in haploinsufficiency.
    CONCLUSIONS: This case adds to the growing body of literature implicating chromosomal structural variants in the manifestation of this disorder and highlights the vital role of cis-acting regulatory elements in the normal expression of this gene. Finally, we propose a protocol for reflex FISH analysis to improve diagnostic efficiency for patients with suspected FOXG1 syndrome.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    Enhancers activate gene transcription in spatial and temporal patterns by interactions with gene promoters. These elements typically reside distal to their target promoter, with which they must interact selectively. Additional elements may contribute to enhancer-promoter specificity, including remote control element sequences within enhancers, tethering elements near promoters, and insulator/boundary elements that disrupt off-target interactions. However, few of these elements have been mapped, and as a result, the mechanisms by which these elements interact remain poorly understood. One impediment is their method of study, namely reporter transgenes in which enhancers are placed adjacent to a heterologous promoter, which may circumvent mechanisms controlling enhancer-promoter specificity and long-range interactions. Here, we report an optimized dual reporter transgene system in Drosophila melanogaster that allows the simultaneous comparison of an enhancer\'s ability to activate proximal and distal fluorescent reporter genes. Testing a panel of fluorescent transgenes in vivo, we found a two-protein combination that allows simultaneous measurement with minimal detection interference. We note differences among four tested enhancers in their ability to regulate a distally placed reporter transgene. These results suggest that enhancers differ in their requirements for promoter interaction and raise important practical considerations when studying enhancer function.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    长期以来,进化趋同一直被认为是自然选择驱动的适应性的主要证据,并为探索进化的可重复性和可预测性提供了机会。近年来,人们对探索趋同进化的遗传机制越来越感兴趣,在某种程度上,由于基因组技术的出现。然而,当前的“基因组学淘金热”在趋同研究中掩盖了大多数特征分类定义相当广泛的现实,导致对结果的不完整或潜在偏见的解释。通过整合深层的“垂直”,收敛的基因组研究将得到极大的改善,具有“横向”知识的自然史知识侧重于分类学多样性的广度。自然历史收藏已经并将继续处于最佳位置,以增加我们对表型多样性的全面了解,数字化和形态特征数据库化的现代实践为我们评估形态收敛程度的能力提供了令人兴奋的改进。将更详细的表型数据与成熟的基因组学领域相结合,将使科学家能够在生物学的一个重要目标上取得进展:了解遗传或分子趋同与表型趋同相关的程度。尽管仅比较生物学或比较基因组学领域就可以分别揭示融合进化的重要见解,在这里,我们认为,自然史收集衍生的表型数据和比较基因组学方法的协同和互补作用在一起阐明高级分类群之间趋同进化的基因组基础方面尤其强大。本文是“基因组学时代的融合进化:新见解和方向”主题的一部分。
    Evolutionary convergence has been long considered primary evidence of adaptation driven by natural selection and provides opportunities to explore evolutionary repeatability and predictability. In recent years, there has been increased interest in exploring the genetic mechanisms underlying convergent evolution, in part, owing to the advent of genomic techniques. However, the current \'genomics gold rush\' in studies of convergence has overshadowed the reality that most trait classifications are quite broadly defined, resulting in incomplete or potentially biased interpretations of results. Genomic studies of convergence would be greatly improved by integrating deep \'vertical\', natural history knowledge with \'horizontal\' knowledge focusing on the breadth of taxonomic diversity. Natural history collections have and continue to be best positioned for increasing our comprehensive understanding of phenotypic diversity, with modern practices of digitization and databasing of morphological traits providing exciting improvements in our ability to evaluate the degree of morphological convergence. Combining more detailed phenotypic data with the well-established field of genomics will enable scientists to make progress on an important goal in biology: to understand the degree to which genetic or molecular convergence is associated with phenotypic convergence. Although the fields of comparative biology or comparative genomics alone can separately reveal important insights into convergent evolution, here we suggest that the synergistic and complementary roles of natural history collection-derived phenomic data and comparative genomics methods can be particularly powerful in together elucidating the genomic basis of convergent evolution among higher taxa. This article is part of the theme issue \'Convergent evolution in the genomics era: new insights and directions\'.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    Attention deficit/hyperactivity disorder (ADHD) is among the most common childhood onset psychiatric behavioral disorders, and the pathogenesis of ADHD is still unclear. Utilizing the latest genome wide association studies (GWAS) data and enhancer map, we explored the brain region related biological pathways associated with ADHD. The GWAS summary data of ADHD was driven from a published study, involving 20,183 ADHD cases and 35,191 healthy controls. The brain-related enhancer map was collected from ENCODE and Roadmap Epigenomics (ENCODE + Roadmap) including 489,581 enhancers. Firstly, the chromosomal enhancer maps of four brain regions were aligned with the ADHD GWAS summary data in order to obtain enhancer SNPs. Then the significant enhancers SNPs were subjected to the gene set enrichment analysis (GSEA) for identifying ADHD associated gene sets. A total of 866 pathways and 4 brain tissues were analyzed in this study. We detected several candidate genes for ADHD, such as AHI1, ALG2 and DNM1. We also detected several candidate biological pathways associated with ADHD, such as Reactome SEMA4D in semaphorin signaling and Reactome NCAM1 interactions. Our findings may provide a novel insight into the complex genetic mechanism of ADHD.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    Autism spectrum disorder (ASD) is a complex developmental disorder with strong genetic components involved. Recent studies have demonstrated the importance of non-coding regulatory variants for complex diseases. To explore the roles of chromosomal enhancer regions in the pathogenesis of ASD, we conducted an integrative analysis of genome-wide association study (GWAS) and brain region related enhancer-gene networks for ASD. The GWAS data of ASD were driven from a published study, involving 7,387 ASD cases and 8,567 controls. The enhancer-gene networks of eight brain regions were used here. The GWAS of ASD was first merged respectively with the enhancer datasets of eight brain regions. Pathway enrichment analysis was then performed to detect ASD associated pathways based on the enhancer-related single nucleotide polymorphism (SNPs) of each brain region. We detected multiple genes with brain region specific or common association signals, such as PGM3 (P value = 1.93 × 10-5 ) and RWDD2A (P value = 1.93 × 10-5 ) for hippocampus middle, and ENPP4 (all P values <0.05), and ENPP5 (all P values <0.05) for seven brain regions. By comparing the pathway enrichment analysis results of various brain regions, several cross brain regions pathways were detected for ASD, such as REACTOME_POTASSIUM_CHANNELS (all P values <0.05) for six brain regions and KEGG_CELL_ADHESION_MOLECULES_CAMS (all P values <0.05) for seven brain regions. In addition, several pathways were also identified for specific brain regions, such as REACTOME_CD28_DEPENDENT_PI3K_AKT_SIGNALING (P value = 4.00 × 10-3 ) for angular gyrus, REACTOME_SIGNALING_BY_CONSTITUTIVELY_ACTIVE_EGFR (P value = 2.22 × 10-3 ) for anterior caudate, and KEGG_PRION_DISEASES (P value = 1.00 × 10-4 ) for germinal matrix. Our results provide novel clues for understanding the genetic basis of ASD. Autism Research 2019, 12: 26-32. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: ASD is a complex developmental disorder with strong genetic components, but the pathogenesis of ASD is still unclear. Using the latest GWAS data and enhancer map, we explored the brain region related biological pathways associated with ASD. Our results provide novel clues for revealing the functional relevance of enhancer variants with ASD and understanding the genetic basis of ASD.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    To explore the associations between chemical elements and attention deficit hyperactivity disorder (ADHD)/intelligence quotient (IQ).
    We applied elements related gene set enrichment analysis (ERGSEA) to explore the relationships between elements and ADHD/IQ. The GWAS dataset of ADHD was derived from the Psychiatric Genomics Consortium, involving 55,374 individuals. The GWAS dataset of IQ was derived from UK Biobank web-based measure (n = 17,862), UK Biobank touchscreen measure (n = 36,257), CHIC consortium (n = 12,441) and five additional cohorts (n = 11,748). Enhancer-gene datasets of eight brain tissues consist of 935 individuals. Utilizing the published GWAS summary and eight brain region-related chromosomal enhancer maps to obtain the SNP association testing signals. The element-gene interaction datasets of 21 elements were downloaded from the comparative toxicogenomics database (CTD).
    ERGSEA observed significant associations between 4 elements and ADHD, such as Al at Hippocampus Middle (P value = 0.040), As at Angular Gyrus (P value = 0.007) and Na at Hippocampus Middle (P value = 0.026). Additionally, ERGSEA identified that 5 elements were associated with IQ, mainly including Al at Dorsolateral Prefrontal Cortex (P value = 0.017), As at Dorsolateral Prefrontal Cortex (P value = 0.004) and Pb at Germinal Matrix (P value = 0.045).
    Our study results provide novel clues for understanding the associations between elements and ADHD/IQ. This study also illustrated the good performance of ERGSEA approach for complex diseases.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    Insomnia is a common sleep disorder whose genetic mechanism remains unknown. The aim of this study is to identify novel genes, gene enrichment sets and enriched tissue/cell types for insomnia considering the differences across different brain regions. We conducted an integrative analysis of genome-wide association study (GWAS) and brain region related enhancer maps. Summary data was derived from a large-scale GWAS of insomnia, involving 113,006 unrelated individuals. The chromosomal enhancer maps of 6 brain regions were then aligned with the GWAS summary data to obtain the association testing results of enhancer regions for insomnia. Gene prioritization, tissue/cell and pathway enrichment analysis were implemented by Data-driven Expression Prioritized Integration for Complex Traits (DEPICT) tool. We identified multiple cross-brain regions or brain-region specific prioritized genes for insomnia, such as MADD (P = .0013 in angular gyrus), PPP2R3C (P = .0319 in cingulate gyrus), CASP9 (P = .0066 in angular gyrus and P = .0278 in hippocampus middle), PLEKHM2 (P = .0032 in angular gyrus, P = .0052 in anterior caudate, P = .0385 in cingulate gyrus and P = .0011 in inferior temporal lobe). This study also detected a group of insomnia associated biological pathways within multiple or specific brain regions, such as REACTOME_SIGNALING_BY_NOTCH and KEGG_GLYCEROPHOSPHOLIPID_METABOLISM. Our results showed that insomnia associated genes were significantly enriched in neural stem cells. Our results highlight a set of potential points, particularly neural stem cells, for subsequent biological studies for insomnia.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    甲基化变化在癌症中很常见,但是了解高甲基化和低甲基化区域如何协调变化,与基因组特征相关联,和影响基因表达需要更好地理解其生物学意义。研究了超甲基化的功能意义,但是低甲基化仍然有限。这里,从患者/对照组收集的成对的表达和甲基化样本,我们试图从B细胞慢性淋巴细胞白血病(B-CLL)样本中更好地表征癌症中发生的基因表达和甲基化变化。
    跨数据集,我们发现,与许多不一致的低和高度保守的超DMRs相比,样本间一致的差异低甲基化区域(C-DMRs)相对较少.然而,hypo-C-DMRs中的基因倾向于与hyper-C-DMRs中的功能拮抗相关,比如分化,细胞周期调节和增殖,提示甲基化变化的协调调节。发现B-CLL中的Hypo-C-DMRs富含关键信号传导途径,例如B细胞受体和p53途径以及B淋巴细胞生成所必需的基因/基序。与高甲基化施加的转录沉默机制相反,Hypo-C-DMRs倾向于接近表达升高的基因。Hypo-C-DMRs倾向于在激活H4K4me1/2/3,H3K79me2和H3K27ac组蛋白修饰的区域中富集。相比之下,多梳抑制复合物2(PRC2)签名,由EZH2,SUZ12,CTCF结合位点标记,压抑的H3K27me3标志,和“抑制/平衡启动子”状态与超C-DMRs相关。大多数hypo-C-DMRs在内含子中发现(36%),3个未翻译区域(29%),和基因间区域(24%)。许多这些基因区域也与增强子重叠。发现3个UTR外显子的CpG甲基化与基因表达呈弱正相关。相比之下,5'UTR中的甲基化与表达呈负相关。为了更好地表征甲基化和表达变化之间的重叠,我们确定了与“凋亡”和“白细胞激活”相关的相关模块。
    尽管疾病表现具有临床异质性,一些甲基化变化,hypo和hyper,在B-CLL中似乎很常见。低甲基化似乎起到了积极的作用,有针对性的,以及在癌症进展中的互补作用,它在癌症过程中以协调的方式与超甲基化相互作用。
    Methylation changes are frequent in cancers, but understanding how hyper- and hypomethylated region changes coordinate, associate with genomic features, and affect gene expression is needed to better understand their biological significance. The functional significance of hypermethylation is well studied, but that of hypomethylation remains limited. Here, with paired expression and methylation samples gathered from a patient/control cohort, we attempt to better characterize the gene expression and methylation changes that take place in cancer from B cell chronic lymphocyte leukemia (B-CLL) samples.
    Across the dataset, we found that consistent differentially hypomethylated regions (C-DMRs) across samples were relatively few compared to the many poorly consistent hypo- and highly conserved hyper-DMRs. However, genes in the hypo-C-DMRs tended to be associated with functions antagonistic to those in the hyper-C-DMRs, like differentiation, cell-cycle regulation and proliferation, suggesting coordinated regulation of methylation changes. Hypo-C-DMRs in B-CLL were found enriched in key signaling pathways like B cell receptor and p53 pathways and genes/motifs essential for B lymphopoiesis. Hypo-C-DMRs tended to be proximal to genes with elevated expression in contrast to the transcription silencing-mechanism imposed by hypermethylation. Hypo-C-DMRs tended to be enriched in the regions of activating H4K4me1/2/3, H3K79me2, and H3K27ac histone modifications. In comparison, the polycomb repressive complex 2 (PRC2) signature, marked by EZH2, SUZ12, CTCF binding-sites, repressive H3K27me3 marks, and \"repressed/poised promoter\" states were associated with hyper-C-DMRs. Most hypo-C-DMRs were found in introns (36 %), 3\' untranslated regions (29 %), and intergenic regions (24 %). Many of these genic regions also overlapped with enhancers. The methylation of CpGs from 3\'UTR exons was found to have weak but positive correlation with gene expression. In contrast, methylation in the 5\'UTR was negatively correlated with expression. To better characterize the overlap between methylation and expression changes, we identified correlation modules that associate with \"apoptosis\" and \"leukocyte activation\".
    Despite clinical heterogeneity in disease presentation, a number of methylation changes, both hypo and hyper, appear to be common in B-CLL. Hypomethylation appears to play an active, targeted, and complementary role in cancer progression, and it interplays with hypermethylation in a coordinated fashion in the cancer process.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

公众号