scholarly journals SOX11 is a lineage-dependency factor and master epigenetic regulator in neuroblastoma

2020 ◽  
Author(s):  
Bieke Decaesteker ◽  
Amber Louwagie ◽  
Siebe Loontiens ◽  
Fanny De Vloed ◽  
Juliette Roels ◽  
...  
Keyword(s):  
Target Genes ◽  
Epigenetic Modification ◽  
Chromatin Accessibility ◽  
Copy Number Alterations ◽  
Specific Expression ◽  
Genome Wide ◽  
Mutation Burden ◽  
Epigenetic Regulator ◽  
Pioneer Factor

ABSTRACTThe pediatric extra-cranial tumor neuroblastoma (NB) is characterised by a low mutation burden while copy number alterations are present in most high-risk cases. We identified SOX11 as a strong lineage dependency transcription factor in adrenergic NB based on recurrent chromosome 2p focal gains and amplifications, its specific expression in the normal sympatho-adrenal lineage and adrenergic NBs and its regulation by multiple adrenergic specific cis-interacting (super-)enhancers. Adrenergic NBs are strongly dependent on high SOX11 expression levels for growth and proliferation. Through genome-wide DNA-binding and transcriptome analysis, we identified and validated functional SOX11 target genes, several of which implicated in chromatin remodeling and epigenetic modification. SOX11 controls chromatin accessibility predominantly affecting distal adrenergic lineage-specific enhancers marked by binding sites of the adrenergic core regulatory circuitry. During normal sympathoblast differentiation we find expression of SOX11 prior to members of the adrenergic core regulatory circuitry. Given the broad control of SOX11 of multiple epigenetic regulatory complexes and its presumed pioneer factor function, we propose that adrenergic NB cells have co-opted the normal role of SOX11 as a crucial regulator of chromatin accessibility and cell identity.

scholarly journals From cytopenia to leukemia: the role of Gfi1 and Gfi1b in blood formation

Blood ◽  
2015 ◽  
Vol 126 (24) ◽  
pp. 2561-2569 ◽  
Author(s):  
Tarik Möröy ◽  
Lothar Vassen ◽  
Brian Wilkes ◽  
Cyrus Khandanpour
Keyword(s):  
Zinc Finger ◽  
Target Genes ◽  
Integration Site ◽  
Wide Spectrum ◽  
Human Leukemia ◽  
Specific Expression ◽  
Hematopoietic Stem ◽  
Proviral Integration Site ◽  
Cell Type Specific Expression

AbstractThe DNA-binding zinc finger transcription factors Gfi1 and Gfi1b were discovered more than 20 years ago and are recognized today as major regulators of both early hematopoiesis and hematopoietic stem cells. Both proteins function as transcriptional repressors by recruiting histone-modifying enzymes to promoters and enhancers of target genes. The establishment of Gfi1 and Gfi1b reporter mice made it possible to visualize their cell type–specific expression and to understand their function in hematopoietic lineages. We now know that Gfi1 is primarily important in myeloid and lymphoid differentiation, whereas Gfi1b is crucial for the generation of red blood cells and platelets. Several rare hematologic diseases are associated with acquired or inheritable mutations in the GFI1 and GFI1B genes. Certain patients with severe congenital neutropenia carry mutations in the GFI1 gene that lead to the disruption of the C-terminal zinc finger domains. Other mutations have been found in the GFI1B gene in families with inherited bleeding disorders. In addition, the Gfi1 locus is frequently found to be a proviral integration site in retrovirus-induced lymphomagenesis, and new, emerging data suggest a role of Gfi1 in human leukemia and lymphoma, underlining the role of both factors not only in normal hematopoiesis, but also in a wide spectrum of human blood diseases.

scholarly journals Epigenetic Influences in the Aetiology of Cancers Arising from Breast and Prostate: A Hypothesised Transgenerational Evolution in Chromatin Accessibility

ISRN Oncology ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Francis L. Martin
Keyword(s):  
Target Genes ◽  
Epigenetic Modification ◽  
Intervention Strategy ◽  
Epidemiological Studies ◽  
Chromatin Accessibility ◽  
Dietary Factors ◽  
Heterocyclic Aromatic Amines ◽  
Tumour Suppressor Genes ◽  
Multistage Model ◽  
Migrant Populations

Epidemiological studies have consistently supported the notion that environmental and/or dietary factors play a central role in the aetiology of cancers of the breast and prostate. However, for more than five decades investigators have failed to identify a single cause-and-effect factor, which could be implicated; identification of a causative entity would allow the implementation of an intervention strategy in at-risk populations. This suggests a more complex pathoaetiology for these cancer sites, compared to others. When one examines the increases or decreases in incidence of specific cancers amongst migrant populations, it is notable that disease arising in colon or stomach requires one or at most two generations to exhibit a change in incidence to match that of high-incidence regions, whereas for breast or prostate cancer, at least three generations are required. This generational threshold could suggest a requirement for nonmutation-driven epigenetic alterations in the F0/F1 generations (parental/offspring adopting a more westernized lifestyle), which then predisposes the inherited genome of subsequent generations to mutagenic/genotoxic alterations leading to the development of sporadic cancer in these target sites. As such, individual susceptibility to carcinogen insult would not be based per se on polymorphisms in activating/detoxifying/repair enzymes, but on elevated accessibility of crucial target genes (e.g., oncogenes, tumour suppressor genes) or hotspots therein to mutation events. This could be termed a genomic susceptibility organizational structure (SOS). Several exposures including alcohol and heavy metals are epigens (i.e., modifiers of the epigenome), whereas others are mutagenic/genotoxic, for example, heterocyclic aromatic amines; humans are continuously and variously exposed to mixtures of these agents. Within such a transgenerational multistage model of cancer development, determining the interaction between epigenetic modification to generate a genomic SOS and genotoxic insult will facilitate a new level of understanding in the aetiology of cancer.

scholarly journals Genome-wide miRNA analysis and integrated network for flavonoid biosynthesis in Osmanthus fragrans

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Yong Shi ◽  
Heng Xia ◽  
Xiaoting Cheng ◽  
Libin Zhang
Keyword(s):  
Secondary Metabolites ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Expression Profiles ◽  
Flavonoid Biosynthesis ◽  
Integrated Network ◽  
Osmanthus Fragrans ◽  
Flavonoid Synthesis ◽  
Genome Wide

AbstractBackgroundOsmanthus fragransis an important economical plant containing multiple secondary metabolites including flavonoids and anthocyanins. During the past years, the roles of miRNAs in regulating the biosynthesis of secondary metabolites in plants have been widely investigated. However, few studies on miRNA expression profiles and the potential roles in regulating flavonoid biosynthesis have been reported inO. fragrans.ResultsIn this study, we used high-throughput sequencing technology to analyze the expression profiles of miRNAs in leaf and flower tissues ofO. fragrans. As a result, 106 conserved miRNAs distributed in 47 families and 88 novel miRNAs were identified. Further analysis showed there were 133 miRNAs differentially expressed in leaves and flowers. Additionally, the potential target genes of miRNAs as well as the related metabolic pathways were predicted. In the end, flavonoid content was measured in flower and leaf tissues and potential role of miR858 in regulating flavonoid synthesis was illustrated inO. fragrans.ConclusionsThis study not only provided the genome-wide miRNA profiles in the flower and leaf tissue ofO. fragrans, but also investigated the potential regulatory role of miR858a in flavonoid synthesis inO. fragrans. The results specifically indicated the connection of miRNAs to the regulation of secondary metabolite biosynthesis in non-model economical plant.

scholarly journals The emerging role of microRNAs in bone remodeling and its therapeutic implications for osteoporosis

2018 ◽  
Vol 38 (3) ◽  
Author(s):  
Qianyun Feng ◽  
Sheng Zheng ◽  
Jia Zheng
Keyword(s):  
Bone Remodeling ◽  
Noncoding Rna ◽  
Target Genes ◽  
Epigenetic Modification ◽  
Therapeutic Implications ◽  
Small Noncoding Rna ◽  
Genetic And Environmental Factors ◽  
Underlying Mechanisms ◽  
Post Transcriptional Regulation

Osteoporosis, a common and multifactorial disease, is influenced by genetic factors and environments. However, the pathogenesis of osteoporosis has not been fully elucidated yet. Recently, emerging evidence suggests that epigenetic modifications may be the underlying mechanisms that link genetic and environmental factors with increased risks of osteoporosis and bone fracture. MicroRNA (miRNA), a major category of small noncoding RNA with 20–22 bases in length, is recognized as one important epigenetic modification. It can mediate post-transcriptional regulation of target genes with cell differentiation and apoptosis. In this review, we aimed to profile the role of miRNA in bone remodeling and its therapeutic implications for osteoporosis. A deeper insight into the role of miRNA in bone remodeling and osteoporosis can provide unique opportunities to develop a novel diagnostic and therapeutic approach of osteoporosis.

scholarly journals Genome-wide effects of chromatin on vitamin D signaling

2020 ◽  
Vol 64 (4) ◽  
pp. R45-R56 ◽  
Author(s):  
Andrea Hanel ◽  
Henna-Riikka Malmberg ◽  
Carsten Carlberg
Keyword(s):  
Vitamin D ◽  
Binding Sites ◽  
Target Genes ◽  
Chromatin Accessibility ◽  
Transcription Start Sites ◽  
Dihydroxyvitamin D ◽  
Genome Wide ◽  
Spatio Temporal ◽  
Vitamin D Signaling ◽  
The Impact

Molecular endocrinology of vitamin D is based on the activation of the transcription factor vitamin D receptor (VDR) by the vitamin D metabolite 1α,25-dihydroxyvitamin D3. This nuclear vitamin D-sensing process causes epigenome-wide effects, such as changes in chromatin accessibility as well as in the contact of VDR and its supporting pioneer factors with thousands of genomic binding sites, referred to as vitamin D response elements. VDR binding enhancer regions loop to transcription start sites of hundreds of vitamin D target genes resulting in changes of their expression. Thus, vitamin D signaling is based on epigenome- and transcriptome-wide shifts in VDR-expressing tissues. Monocytes are the most responsive cell type of the immune system and serve as a paradigm for uncovering the chromatin model of vitamin D signaling. In this review, an alternative approach for selecting vitamin D target genes is presented, which are most relevant for understanding the impact of vitamin D endocrinology on innate immunity. Different scenarios of the regulation of primary upregulated vitamin D target genes are presented, in which vitamin D-driven super-enhancers comprise a cluster of persistent (constant) and/or inducible (transient) VDR-binding sites. In conclusion, the spatio-temporal VDR binding in the context of chromatin is most critical for the regulation of vitamin D target genes.

Molecular network of chromatin immunoprecipitation followed by deep sequencing-based vitamin D receptor target genes

2013 ◽  
Vol 19 (8) ◽  
pp. 1035-1045 ◽  
Author(s):  
Jun-ichi Satoh ◽  
Hiroko Tabunoki
Keyword(s):  
Multiple Sclerosis ◽  
Vitamin D ◽  
Vitamin D Receptor ◽  
Deep Sequencing ◽  
Immune Cells ◽  
Chromatin Immunoprecipitation ◽  
Target Genes ◽  
Molecular Network ◽  
Genome Wide

Background: Vitamin D is a liposoluble vitamin essential for calcium metabolism. The ligand-bound vitamin D receptor (VDR), heterodimerized with retinoid X receptor, interacts with vitamin D response elements (VDREs) to regulate gene expression. Vitamin D deficiency due to insufficient sunlight exposure confers an increased risk for multiple sclerosis (MS). Objective: To study a protective role of vitamin D in multiple sclerosis (MS), it is important to characterize the global molecular network of VDR target genes (VDRTGs) in immune cells. Methods: We identified genome-wide VDRTGs collectively from two distinct chromatin immunoprecipitation followed by deep sequencing (ChIP-Seq) datasets of VDR-binding sites derived from calcitriol-treated human cells of B cell and monocyte origins. We mapped short reads of next generation sequencing (NGS) data on hg19 with Bowtie, detected the peaks with Model-based Analysis of ChIP-Seq (MACS), and identified genomic locations by GenomeJack, a novel genome viewer for NGS platforms. Results: We found 2997 stringent peaks distributed on protein-coding genes, chiefly located in the promoter and the intron on VDRE DR3 sequences. However, the corresponding transcriptome data verified calcitriol-induced upregulation of only a small set of VDRTGs. The molecular network of 1541 calcitriol-responsive VDRTGs showed a significant relationship with leukocyte transendothelial migration, Fcγ receptor-mediated phagocytosis, and transcriptional regulation by VDR, suggesting a pivotal role of genome-wide VDRTGs in immune regulation. Conclusion: These results suggest the working hypothesis that persistent deficiency of vitamin D might perturb the complex network of VDRTGs in immune cells, being responsible for induction of an autoimmune response causative for MS.

scholarly journals GnRH Receptor Expression and Reproductive Function Depend on JUN in GnRH Receptor‒Expressing Cells

Endocrinology ◽  
2018 ◽  
Vol 159 (3) ◽  
pp. 1496-1510 ◽  
Author(s):  
Carrie R Jonak ◽  
Nancy M Lainez ◽  
Ulrich Boehm ◽  
Djurdjica Coss
Keyword(s):  
Target Genes ◽  
Reproductive Function ◽  
Gnrh Receptor ◽  
Receptor Expression ◽  
Specific Expression ◽  
Α Subunit ◽  
Estrous Cycles ◽  
Hormone Synthesis

Abstract Gonadotropin-releasing hormone (GnRH) from the hypothalamus regulates synthesis and secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the anterior pituitary gonadotropes. LH and FSH are heterodimers composed of a common α-subunit and unique β-subunits, which provide biological specificity and are limiting components of mature hormone synthesis. Gonadotrope cells respond to GnRH via specific expression of the GnRH receptor (Gnrhr). GnRH induces the expression of gonadotropin genes and of the Gnrhr by activation of specific transcription factors. The JUN (c-Jun) transcription factor binds to AP-1 sites in the promoters of target genes and mediates induction of the FSHβ gene and of the Gnrhr in gonadotrope-derived cell lines. To analyze the role of JUN in reproductive function in vivo, we generated a mouse model that lacks JUN specifically in GnRH receptor‒expressing cells (conditional JUN knockout; JUN-cKO). JUN-cKO mice displayed profound reproductive anomalies such as reduced LH levels resulting in lower gonadal steroid levels, longer estrous cycles in females, and diminished sperm numbers in males. Unexpectedly, FSH levels were unchanged in these animals, whereas Gnrhr expression in the pituitary was reduced. Steroidogenic enzyme expression was reduced in the gonads of JUN-cKO mice, likely as a consequence of reduced LH levels. GnRH receptor‒driven Cre activity was detected in the hypothalamus but not in the GnRH neuron. Female, but not male, JUN-cKO mice exhibited reduced GnRH expression. Taken together, our results demonstrate that GnRH receptor‒expression levels depend on JUN and are critical for reproductive function.

scholarly journals Genetics, Epigenetics, and Gender Impact in Axial-Spondyloarthritis Susceptibility: An Update on Genetic Polymorphisms and Their Sex Related Associations

2021 ◽  
Vol 12 ◽  
Author(s):  
Maria Sole Chimenti ◽  
Carlo Perricone ◽  
Arianna D’Antonio ◽  
Mario Ferraioli ◽  
Paola Conigliaro ◽  
...  
Keyword(s):  
Epigenetic Modification ◽  
Chromosome Instability ◽  
Epigenetic Factors ◽  
Biological Drugs ◽  
Specific Expression ◽  
Previous Infection ◽  
Inflammatory Bowel ◽  
Males And Females ◽  
And Gender

Spondyloarthritis (SpA) is a group of chronic inflammatory rheumatic disease that can be divided into predominantly axial or predominantly peripheral involvement, with or without associated psoriasis, inflammatory bowel disease or previous infection. Axial SpA (axSpA) encompasses ankylosing spondylitis (AS) with radiological sacroiliitis, and a type without radiographic sacroiliitis, called “non-radiographic axial SpA” (nr-axSpA). Males and females show large differences in their susceptibility to SpA, such as distinctions in clinical patterns, phenotypes and in therapeutical response, particularly to TNF inhibitors (TNFi). Several studies indicate that AS women have doubled risk to failure TNFi compared with males. This diversity in drugs’ efficacy among women and men may be caused by differences in the balance of sex hormones and in gene-specific expression likely triggered by X-chromosome instability and gene-specific epigenetic modifications. Evidence reported that polymorphisms in microRNAs on X- and other chromosomes, such as miR-146a, miR-155, miR-125a-5p, miR-151a-3p and miR-22-3p, miR-199a-5p could be involved in the different clinical presentation of SpA, as well as disease activity. In addition, association with non−response to TNFi treatment and presence of IRAK3 and CHUCK genes in SpA patients was recently detected. Finally, polymorphisms in genes involved in IL-23/IL-17 pathway, such as in drug pharmacodynamics and pharmacokinetics may have a role in response to TNFi, IL17i, and IL23i. A major understanding of genomic variability could help in the development of new therapeutic targets or in taking advantages of different mechanisms of action of biological drugs. Moving from the multifactorial etiology of disease, the present review aims at evaluating genetic and epigenetic factors and their relationship with sex and bDMARDs response, helping to investigate the different expression among males and females of genes on X- and other chromosomes, as well as mi-RNA, to highlight relationships between sex and occurrence of specific phenotypes and symptoms of the disease. Moreover, the role of the epigenetic modification in relation to immune-regulatory mechanisms will be evaluated.

scholarly journals Genome-wide reduction in chromatin accessibility and unique transcription factor footprints in endothelial cells and fibroblasts in scleroderma skin

2020 ◽  
Author(s):  
Pei-Suen Tsou ◽  
Pamela J. Palisoc ◽  
Mustafa Ali ◽  
Dinesh Khanna ◽  
Amr H Sawalha
Keyword(s):  
Endothelial Cells ◽  
Transcription Factor ◽  
Transcription Factors ◽  
Target Genes ◽  
Critical Role ◽  
Vascular Complications ◽  
Chromatin Accessibility ◽  
Unknown Etiology ◽  
Healthy Controls ◽  
Genome Wide

AbstractSystemic sclerosis (SSc) is a rare autoimmune disease of unknown etiology characterized by widespread fibrosis and vascular complications. We utilized an assay for genome-wide chromatin accessibility to examine the chromatin landscape and transcription factor footprints in both endothelial cells (ECs) and fibroblasts isolated from healthy controls and patients with diffuse cutaneous (dc) SSc. In both cell types, chromatin accessibility was significantly reduced in SSc patients compared to healthy controls. Genes annotated from differentially accessible chromatin regions were enriched in pathways and gene ontologies involved in the nervous system. In addition, our data revealed that chromatin binding of transcription factors SNAI2, ETV2, and ELF1 was significantly increased in dcSSc ECs, while recruitment of RUNX1 and RUNX2 was enriched in dcSSc fibroblasts. Significant elevation of SNAI2 and ETV2 levels in dcSSc ECs, and RUNX2 levels in dcSSc fibroblasts were confirmed. Further analysis of publicly available ETV2-target genes suggests that ETV2 may play a critical role in EC dysfunction in dcSSc. Our data, for the first time, uncovered the chromatin blueprint of dcSSc ECs and fibroblasts, and suggested that neural-related characteristics of SSc ECs and fibroblasts could be a culprit for dysregulated angiogenesis and enhanced fibrosis. Targeting these pathways and the key transcription factors identified might present novel therapeutic approaches for this disease.

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