scholarly journals Contiguous Erosion of the Inactive X in Human Pluripotency Concludes With Global DNA Hypomethylation

2020 ◽  
Author(s):  
Prakhar Bansal ◽  
Stefan F. Pinter
Keyword(s):  
X Chromosome ◽  
Pluripotent Stem Cells ◽  
Regulatory Element ◽  
Chromatin Accessibility ◽  
Integrated Analysis ◽  
Epigenetic Landscape ◽  
Dna Hypomethylation ◽  
Non Coding Rna ◽  
Genome Wide ◽  
Long Non Coding Rna

SUMMARYFemale human pluripotent stem cells (hPSCs) are prone to undergoing X chromosome erosion (XCE), a progressive loss of key epigenetic features on the inactive X that initiates with repression of XIST, the long non-coding RNA required for X inactivation. As a result, previously silenced genes on the eroding X (Xe) reactivate, some of which are thought to provide selective advantages. To-date, the sporadic and progressive nature of XCE has largely obscured its scale, dynamics, and key transition events.To address this knowledge gap, we performed an integrated analysis of DNA methylation (DNAme), chromatin accessibility, and gene expression across hundreds of hPSC samples. Differential methylation across the Xe enables ordering female hPSCs across a trajectory of XCE from initiation to terminal stages. Our results identify a crucial cis-regulatory element for XIST expression, trace contiguously growing domains of reactivation to a few euchromatic origins on the Xi, and indicate that the late-stage Xe impairs DNAme genome-wide. Surprisingly, from this altered epigenetic landscape emerge select features of naïve pluripotency, suggesting its link to X chromosome dosage may be partially conserved in human embryonic development.

scholarly journals A novel cis regulatory element regulates human XIST in CTCF-dependent manner

2019 ◽  
Author(s):  
Rini Shah ◽  
Ashwin Kelkar ◽  
Sanjeev Galande
Keyword(s):  
Transcription Factors ◽  
X Chromosome ◽  
Promoter Region ◽  
Regulatory Element ◽  
X Chromosome Inactivation ◽  
Dependent Manner ◽  
Pluripotency Factors ◽  
Factors Influencing ◽  
Non Coding Rna ◽  
Long Non Coding Rna

ABSTRACTThe long non-coding RNA XIST is the master regulator for the process of X chromosome inactivation in mammalian females. Here we report the existence of a hitherto uncharacterized cis regulatory element within the first exon of human XIST, which by associating with the promoter region through chromatin looping defines the transcriptional status of XIST. This interaction is brought about by CTCF, which in turn assists towards the maintenance of YY1 binding at the promoter and governs XIST transcription. Strikingly, the cis element is competitively bound by pluripotency factors and CTCF, wherein the enrichment of the former disrupts its interaction with the promoter, leading to downregulation of XIST. Collectively, our study uncovers the combinatorial effect of multiple epigenetic and transcription factors influencing XIST expression during the initiation and maintenance phases of inactivation.

scholarly journals A novel cis regulatory element regulates human XIST in CTCF-dependent manner

2021 ◽  
Author(s):  
Rini Shah ◽  
Ankita Sharma ◽  
Ashwin Kelkar ◽  
Kundan Sengupta ◽  
Sanjeev Galande
Keyword(s):  
X Chromosome ◽  
Regulatory Element ◽  
Maintenance Phase ◽  
Transcriptional Regulators ◽  
X Chromosome Inactivation ◽  
Dependent Manner ◽  
Initiation Phase ◽  
Pluripotency Factors ◽  
Non Coding Rna ◽  
Long Non Coding Rna

The long non-coding RNA XIST is the master regulator for the process of X chromosome inactivation (XCI) in mammalian females. Here we report the existence of a hitherto uncharacterized cis regulatory element (cRE) within the first exon of human XIST , which determines the transcriptional status of XIST during the initiation and maintenance phases of XCI. In the initiation phase, pluripotency factors bind to this cRE and keep XIST repressed. In the maintenance phase of XCI, the cRE is enriched for CTCF which activates XIST transcription. By employing a CRISPR-dCas9-KRAB based interference strategy, we demonstrate that binding of CTCF to the newly identified cRE is critical for regulating XIST in a YY1-dependent manner. Collectively, our study uncovers the combinatorial effect of multiple transcriptional regulators influencing XIST expression during the initiation and maintenance phases of XCI.

scholarly journals Pharmacogenomics of Lithium Response in Bipolar Disorder

2021 ◽  
Vol 14 (4) ◽  
pp. 287
Author(s):  
Courtney M. Vecera ◽  
Gabriel R. Fries ◽  
Lokesh R. Shahani ◽  
Jair C. Soares ◽  
Rodrigo Machado-Vieira
Keyword(s):  
Bipolar Disorder ◽  
Association Studies ◽  
Mood Stabilizer ◽  
Genome Wide Association Studies ◽  
Nucleotide Polymorphisms ◽  
Non Coding Rna ◽  
Genome Wide ◽  
Lithium Response ◽  
Genetic Loading ◽  
Long Non Coding Rna

Despite being the most widely studied mood stabilizer, researchers have not confirmed a mechanism for lithium’s therapeutic efficacy in Bipolar Disorder (BD). Pharmacogenomic applications may be clinically useful in the future for identifying lithium-responsive patients and facilitating personalized treatment. Six genome-wide association studies (GWAS) reviewed here present evidence of genetic variations related to lithium responsivity and side effect expression. Variants were found on genes regulating the glutamate system, including GAD-like gene 1 (GADL1) and GRIA2 gene, a mutually-regulated target of lithium. In addition, single nucleotide polymorphisms (SNPs) discovered on SESTD1 may account for lithium’s exceptional ability to permeate cell membranes and mediate autoimmune and renal effects. Studies also corroborated the importance of epigenetics and stress regulation on lithium response, finding variants on long, non-coding RNA genes and associations between response and genetic loading for psychiatric comorbidities. Overall, the precision medicine model of stratifying patients based on phenotype seems to derive genotypic support of a separate clinical subtype of lithium-responsive BD. Results have yet to be expounded upon and should therefore be interpreted with caution.

scholarly journals Functional genomics of autoimmune diseases

2021 ◽  
pp. annrheumdis-2019-216794
Author(s):  
Akari Suzuki ◽  
Matteo Maurizio Guerrini ◽  
Kazuhiko Yamamoto
Keyword(s):  
Autoimmune Diseases ◽  
Association Studies ◽  
Linkage Disequilibrium Block ◽  
Causal Variant ◽  
Genome Wide Association Studies ◽  
Coding Region ◽  
Risk Variants ◽  
Non Coding Rna ◽  
Genome Wide ◽  
Long Non Coding Rna

For more than a decade, genome-wide association studies have been applied to autoimmune diseases and have expanded our understanding on the pathogeneses. Genetic risk factors associated with diseases and traits are essentially causative. However, elucidation of the biological mechanism of disease from genetic factors is challenging. In fact, it is difficult to identify the causal variant among multiple variants located on the same haplotype or linkage disequilibrium block and thus the responsible biological genes remain elusive. Recently, multiple studies have revealed that the majority of risk variants locate in the non-coding region of the genome and they are the most likely to regulate gene expression such as quantitative trait loci. Enhancer, promoter and long non-coding RNA appear to be the main target mechanisms of the risk variants. In this review, we discuss functional genetics to challenge these puzzles.

scholarly journals Integrated Analysis of Long Non-Coding RNA and mRNA Expression Profiles in Testes of Calves and Sexually Mature Wandong Bulls (Bos taurus)

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2006
Author(s):  
Hongyu Liu ◽  
Ibrar Muhammad Khan ◽  
Huiqun Yin ◽  
Xinqi Zhou ◽  
Muhammad Rizwan ◽  
...  
Keyword(s):  
Target Genes ◽  
Expression Profiles ◽  
Age Groups ◽  
Adherens Junction ◽  
Integrated Analysis ◽  
Sequencing Data ◽  
Non Coding Rna ◽  
Non Coding Rnas ◽  
Rna Interaction ◽  
Long Non Coding Rna

The mRNAs and long non-coding RNAs axes are playing a vital role in the regulating of post-transcriptional gene expression. Thereby, elucidating the expression pattern of mRNAs and long non-coding RNAs underlying testis development is crucial. In this study, mRNA and long non-coding RNAs expression profiles were investigated in 3-month-old calves and 3-year-old mature bulls’ testes by total RNA sequencing. Additionally, during the gene level analysis, 21,250 mRNAs and 20,533 long non-coding RNAs were identified. As a result, 7908 long non-coding RNAs (p-adjust < 0.05) and 5122 mRNAs (p-adjust < 0.05) were significantly differentially expressed between the distinct age groups. In addition, gene ontology and biological pathway analyses revealed that the predicted target genes are enriched in the lysine degradation, cell cycle, propanoate metabolism, adherens junction and cell adhesion molecules pathways. Correspondingly, the RT-qPCR validation results showed a strong consistency with the sequencing data. The source genes for the mRNAs (CCDC83, DMRTC2, HSPA2, IQCG, PACRG, SPO11, EHHADH, SPP1, NSD2 and ACTN4) and the long non-coding RNAs (COX7A2, COX6B2, TRIM37, PRM2, INHBA, ERBB4, SDHA, ATP6VOA2, FGF9 and TCF21) were found to be actively associated with bull sexual maturity and spermatogenesis. This study provided a comprehensive catalog of long non-coding RNAs in the bovine testes and also offered useful resources for understanding the differences in sexual development caused by the changes in the mRNA and long non-coding RNA interaction expressions between the immature and mature stages.

scholarly journals Epigenetic Insights and Potential Modifiers as Therapeutic Targets in β–Thalassemia

Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 755
Author(s):  
Nur Atikah Zakaria ◽  
Md Asiful Islam ◽  
Wan Zaidah Abdullah ◽  
Rosnah Bahar ◽  
Abdul Aziz Mohamed Yusoff ◽  
...  
Keyword(s):  
Gene Expression ◽  
Clinical Presentation ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
Dna Hypomethylation ◽  
Considerable Research ◽  
Non Coding Rna ◽  
Hbf Level ◽  
Long Non Coding Rna ◽  
Globin Gene Expression

Thalassemia, an inherited quantitative globin disorder, consists of two types, α– and β–thalassemia. β–thalassemia is a heterogeneous disease that can be asymptomatic, mild, or even severe. Considerable research has focused on investigating its underlying etiology. These studies found that DNA hypomethylation in the β–globin gene cluster is significantly related to fetal hemoglobin (HbF) elevation. Histone modification reactivates γ-globin gene expression in adults and increases β–globin expression. Down-regulation of γ–globin suppressor genes, i.e., BCL11A, KLF1, HBG-XMN1, HBS1L-MYB, and SOX6, elevates the HbF level. β–thalassemia severity is predictable through FLT1, ARG2, NOS2A, and MAP3K5 gene expression. NOS2A and MAP3K5 may predict the β–thalassemia patient’s response to hydroxyurea, a HbF-inducing drug. The transcription factors NRF2 and BACH1 work with antioxidant enzymes, i.e., PRDX1, PRDX2, TRX1, and SOD1, to protect erythrocytes from oxidative damage, thus increasing their lifespan. A single β–thalassemia-causing mutation can result in different phenotypes, and these are predictable by IGSF4 and LARP2 methylation as well as long non-coding RNA expression levels. Finally, the coinheritance of β–thalassemia with α–thalassemia ameliorates the β–thalassemia clinical presentation. In conclusion, the management of β–thalassemia is currently limited to genetic and epigenetic approaches, and numerous factors should be further explored in the future.

Genome-wide analysis of long non-coding RNA expression profiles in keratinocytes from psoriasis skin

2021 ◽  
Author(s):  
Longlong Luo ◽  
Nupur khera ◽  
Andor Pivarcsi ◽  
Ankit Srivastava ◽  
Lorenzo Pasquali ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Rna Expression ◽  
Genome Wide Analysis ◽  
Non Coding Rna ◽  
Genome Wide ◽  
Long Non Coding Rna

scholarly journals A role for YY1 in sex-biased transcription revealed through X-linked promoter activity and allelic binding analyses

2016 ◽  
Author(s):  
Chih-yu Chen ◽  
Wenqiang Shi ◽  
Allison M. Matthews ◽  
Yifeng Li ◽  
David J. Arenillas ◽  
...  
Keyword(s):  
X Chromosome ◽  
Specific Binding ◽  
Positive Association ◽  
Binding Motif ◽  
Transcription Start ◽  
Transcription Factor Binding Motif ◽  
Transcription Start Sites ◽  
Non Coding Rna ◽  
Allelic Gene ◽  
Long Non Coding Rna

AbstractSex differences in susceptibility and progression have been reported in numerous diseases. Female cells have two copies of the X chromosome with X-chromosome inactivation imparting mono-allelic gene silencing for dosage compensation. However, a subset of genes, named escapees, escape silencing and are transcribed bi-allelically resulting in sexual dimorphism. Here we conducted analyses of the sexes using human datasets to gain perspectives in such regulation. We identified transcription start sites of escapees (escTSSs) based on higher transcription levels in female cells using FANTOM5 CAGE data. Significant over-representations of YY1 transcription factor binding motif and ChIP-seq peaks around escTSSs highlighted its positive association with escapees. Furthermore, YY1 occupancy is significantly biased towards the inactive X (Xi) at long non-coding RNA loci that are frequent contacts of Xi-specific superloops. Our study elucidated the importance of YY1 on transcriptional activity on Xi in general through sequence-specific binding, and its involvement at superloop anchors.

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