'; ?> geneimprint : Hot off the Press http://www.geneimprint.com/site/hot-off-the-press Daily listing of the most recent articles in epigenetics and imprinting, collected from the PubMed database. en-us Tue, 26 May 2020 22:04:50 EDT Tue, 26 May 2020 22:04:50 EDT jirtle@radonc.duke.edu james001@jirtle.com Discovery of new epigenomics-based biomarkers and the early diagnosis of neurodegenerative diseases. Lee D, Choi YH, Seo J, Kim JK, Lee SB
Ageing Res Rev (May 2020)

Treatment options for many neurodegenerative diseases are limited due to the lack of early diagnostic procedures that allow timely delivery of therapeutic agents to affected neurons prior to cell death. While notable advances have been made in neurodegenerative disease biomarkers, whether or not the biomarkers discovered to date are useful for early diagnosis remains an open question. Additionally, the reliability of these biomarkers has been disappointing, due in part to the large dissimilarities between the tissues traditionally used to source biomarkers and primarily diseased neurons. In this article, we review the potential viability of atypical epigenetic and/or consequent transcriptional alterations (ETAs) as biomarkers of early-stage neurodegenerative disease, and present our perspectives on the discovery and practical use of such biomarkers in patient-derived neural samples using single-cell level analyses, thereby greatly enhancing the reliability of biomarker application.]]>
Wed, 31 Dec 1969 19:00:00 EST
Enhancer Predictions and Genome-Wide Regulatory Circuits. Beer MA, Shigaki D, Huangfu D
Annu Rev Genomics Hum Genet (May 2020)

Spatiotemporal control of gene expression during development requires orchestrated activities of numerous enhancers, which are -regulatory DNA sequences that, when bound by transcription factors, support selective activation or repression of associated genes. Proper activation of enhancers is critical during embryonic development, adult tissue homeostasis, and regeneration, and inappropriate enhancer activity is often associated with pathological conditions such as cancer. Multiple consortia [e.g., the Encyclopedia of DNA Elements (ENCODE) Consortium and National Institutes of Health Roadmap Epigenomics Mapping Consortium] and independent investigators have mapped putative regulatory regions in a large number of cell types and tissues, but the sequence determinants of cell-specific enhancers are not yet fully understood. Machine learning approaches trained on large sets of these regulatory regions can identify core transcription factor binding sites and generate quantitative predictions of enhancer activity and the impact of sequence variants on activity. Here, we review these computational methods in the context of enhancer prediction and gene regulatory network models specifying cell fate. Expected final online publication date for the , Volume 21 is August 31, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.]]>
Wed, 31 Dec 1969 19:00:00 EST
How to improve mouse cloning. Ogura A
Theriogenology (Jul 2020)

The mouse is the most extensively used mammalian laboratory species in biology and medicine because of the ready availability of a wide variety of defined genetic and gene-modified strains and abundant genetic information. Its small size and rapid generation turnover are also advantages compared with other experimental animals. Using these advantages, somatic cell nuclear transfer (SCNT) in mice has provided invaluable information on epigenetics related to SCNT technology and cloning, playing a leading role in relevant technical improvements. These improvements include treatment with histone deacetylase inhibitors, correction of Xist gene expression (controlling X chromosome inactivation), and removal of methylated histones from SCNT-generated embryos, which have proven to be effective for SCNT cloning of other species. However, even with the best combination of these treatments, the birth rate in cloned offspring is still lower than intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF). One remaining issue associated with SCNT is placental enlargement (hyperplasia) found in late pregnancy, but this abnormality might not be a major cause for the low efficiency of SCNT because many SCNT-derived embryos die before their placentas start to enlarge at midgestation (early postimplantation stage). It is known that, at this stage, undifferentiated trophoblast cells in the extraembryonic tissue of SCNT-derived embryos fail to proliferate. Understanding the molecular mechanisms is essential for further technical improvements of mouse SCNT, which might also provide clues for technical breakthroughs in mammalian SCNT and cloning in general.]]>
Wed, 31 Dec 1969 19:00:00 EST
Histone Deacetylases (HDACs): Evolution, Specificity, Role in Transcriptional Complexes, and Pharmacological Actionability. Milazzo G, Mercatelli D, Di Muzio G, Triboli L, De Rosa P, Perini G, Giorgi FM
Genes (Basel) (May 2020)

Histone deacetylases (HDACs) are evolutionary conserved enzymes which operate by removing acetyl groups from histones and other protein regulatory factors, with functional consequences on chromatin remodeling and gene expression profiles. We provide here a review on the recent knowledge accrued on the zinc-dependent HDAC protein family across different species, tissues, and human pathologies, specifically focusing on the role of HDAC inhibitors as anti-cancer agents. We will investigate the chemical specificity of different HDACs and discuss their role in the human interactome as members of chromatin-binding and regulatory complexes.]]>
Wed, 31 Dec 1969 19:00:00 EST
OCT3/4-binding sequence-dependent maintenance of the unmethylated state of CTCF-binding sequences with DNA demethylation and suppression of de novo DNA methylation in the H19 imprinted control region. Hori N, Kubo S, Sakasegawa T, Sakurai C, Hatsuzawa K
Gene (Jun 2020)

DNA demethylation and suppression of de novo DNA methylation are activities that maintain an unmethylated state. However, the strength of these two activities at the same locus has not been estimated separately. Furthermore, the association between these two activities and the unmethylated state remains unclear. Octamer-binding transcription factor-binding sequences (OBSs) and CCCTC-binding factor-binding sequences (CBSs) within the mouse H19-imprinted control region (ICR) are involved in the induction of DNA demethylation and maintenance of the unmethylated state in mouse undifferentiated embryonic cell lines. To reveal the association between the two cis-elements and the two unmethylated state maintenance activities in maintaining the unmethylated state of the ICR, we evaluated the altered DNA methylation levels at sites that were initially methylated or unmethylated using a stable transfection-based assay, and estimated the strength of the two unmethylated state maintenance activities separately via a Poisson process model that described the DNA methylation state regulatory process. Although DNA demethylation depending on OBSs affected almost the entire ICR, DNA demethylation depending on CBSs occurred near CBSs, resulting in redundant demethylation of CBS regions. Detailed analysis of the CBS4 region suggested that OBSs were required to induce unmethylated state maintenance activities, and that CBSs-dependent activities contributed, but diminished, during incubation when protection of the CBS4 region by OBSs-dependent activities was absent. Analysis via the Poisson process model indicated that the unmethylated state at the CBS4 region was maintained by OBSs-dependent suppression of de novo DNA methylation rather than DNA demethylation. We propose that the hierarchical regulation of redundant protection of the CBS region via cooperation between the two unmethylated state maintenance activities is a potential function of the ICR that effectively maintains allele-specific methylation status in the same DNA sequence.]]>
Wed, 31 Dec 1969 19:00:00 EST
DNA methylation analysis in plants: review of computational tools and future perspectives. Omony J, Nussbaumer T, Gutzat R
Brief Bioinform (May 2020)

Genome-wide DNA methylation studies have quickly expanded due to advances in next-generation sequencing techniques along with a wealth of computational tools to analyze the data. Most of our knowledge about DNA methylation profiles, epigenetic heritability and the function of DNA methylation in plants derives from the model species Arabidopsis thaliana. There are increasingly many studies on DNA methylation in plants-uncovering methylation profiles and explaining variations in different plant tissues. Additionally, DNA methylation comparisons of different plant tissue types and dynamics during development processes are only slowly emerging but are crucial for understanding developmental and regulatory decisions. Translating this knowledge from plant model species to commercial crops could allow the establishment of new varieties with increased stress resilience and improved yield. In this review, we provide an overview of the most commonly applied bioinformatics tools for the analysis of DNA methylation data (particularly bisulfite sequencing data). The performances of a selection of the tools are analyzed for computational time and agreement in predicted methylated sites for A. thaliana, which has a smaller genome compared to the hexaploid bread wheat. The performance of the tools was benchmarked on five plant genomes. We give examples of applications of DNA methylation data analysis in crops (with a focus on cereals) and an outlook for future developments for DNA methylation status manipulations and data integration.]]>
Wed, 31 Dec 1969 19:00:00 EST
Epigenomics and gene regulation in mammalian social systems. Guerrero TP, Fickel J, Benhaiem S, Weyrich A
Curr Zool (Jun 2020)

Social epigenomics is a new field of research that studies how the social environment shapes the epigenome and how in turn the epigenome modulates behavior. We focus on describing known gene-environment interactions (GEIs) and epigenetic mechanisms in different mammalian social systems. To illustrate how epigenetic mechanisms integrate GEIs, we highlight examples where epigenetic mechanisms are associated with social behaviors and with their maintenance through neuroendocrine, locomotor, and metabolic responses. We discuss future research trajectories and open questions for the emerging field of social epigenomics in nonmodel and naturally occurring social systems. Finally, we outline the technological advances that aid the study of epigenetic mechanisms in the establishment of GEIs and vice versa.]]>
Wed, 31 Dec 1969 19:00:00 EST
HIV-1 Proviral Transcription and Latency in the New Era. Shukla A, Ramirez NP, D'Orso I
Viruses (May 2020)

Three decades of extensive work in the HIV field have revealed key viral and host cell factors controlling proviral transcription. Various models of transcriptional regulation have emerged based on the collective information from in vitro assays and work in both immortalized and primary cell-based models. Here, we provide a recount of the past and current literature, highlight key regulatory aspects, and further describe potential limitations of previous studies. We particularly delve into critical steps of HIV gene expression including the role of the integration site, nucleosome positioning and epigenomics, and the transition from initiation to pausing and pause release. We also discuss open questions in the field concerning the generality of previous regulatory models to the control of HIV transcription in patients under suppressive therapy, including the role of the heterogeneous integration landscape, clonal expansion, and bottlenecks to eradicate viral persistence. Finally, we propose that building upon previous discoveries and improved or yet-to-be discovered technologies will unravel molecular mechanisms of latency establishment and reactivation in a "new era".]]>
Wed, 31 Dec 1969 19:00:00 EST
Imprinted genes in clinical exome sequencing: Review of 538 cases and exploration of mouse-human conservation in the identification of novel human disease loci. Bhoj EJ, Rajabi F, Baker SW, Santani A, Tan WH
Eur J Med Genet (Jun 2020)

Human imprinting disorders cause a range of dysmorphic and neurocognitive phenotypes, and they may elude traditional molecular diagnosis such exome sequencing. The discovery of novel disorders related to imprinted genes has lagged behind traditional Mendelian disorders because current diagnostic technology, especially unbiased testing, has limited utility in their discovery. To identify novel imprinting disorders, we reviewed data for every human gene hypothesized to be imprinted, identified each mouse ortholog, determined its imprinting status in the mouse, and analyzed its function in humans and mice. We identified 17 human genes that are imprinted in both humans and mice, and have functional data in mice or humans to suggest that dysregulated expression would lead to an abnormal phenotype in humans. These 17 genes, along with known imprinted genes, were preferentially flagged 538 clinical exome sequencing tests. The identified genes were: DIRAS3 [1p31.3], TP73 [1p36.32], SLC22A3 [6q25.3], GRB10 [7p12.1], DDC [7p12.2], MAGI2 [7q21.11], PEG10 [7q21.3], PPP1R9A [7q21.3], CALCR [7q21.3], DLGAP2 [8p23.3], GLIS3 [9p24.2], INPP5F [10q26.11], ANO1 [11q13.3], SLC38A4 [12q13.11], GATM [15q21.1], PEG3 [19q13.43], and NLRP2 [19q13.42]. In the 538 clinical cases, eight cases (1.7%) reported variants in a causative known imprinted gene. There were 367/758 variants (48.4%) in imprinted genes that were not known to cause disease, but none of those variants met the criteria for clinical reporting. Imprinted disorders play a significant role in human disease, and additional human imprinted disorders remain to be discovered. Therefore, evolutionary conservation is a potential tool to identify novel genes involved in human imprinting disorders and to identify them in clinical testing.]]>
Wed, 31 Dec 1969 19:00:00 EST
Transcriptional memory in skeletal muscle. Don't forget (to) exercise. Beiter T, Nieß AM, Moser D
J Cell Physiol (Jul 2020)

Transcriptional memory describes an ancient and highly conserved form of cellular learning that enables cells to benefit from recent experience by retaining a mitotically inheritable but reversible memory of the initial transcriptional response when encountering an environmental or physiological stimulus. Herein, we will review recent progress made in the understanding of how cells can make use of diverse constituents of the epigenetic toolbox to retain a transcriptional memory of past states and perturbations. Specifically, we will outline how these mechanisms will help to improve our understanding of skeletal muscle plasticity in health and disease. We describe the epigenetic road map that allows skeletal muscle fibers to navigate through training-induced adaptation processes, and how epigenetic memory marks can preserve an autobiographical history of lifestyle behavior changes, pathological challenges, and aging. We will further consider some key findings in the field of exercise epigenomics to emphasize major challenges when interpreting dynamic changes in the chromatin landscape in response to acute exercise and training.]]>
Wed, 31 Dec 1969 19:00:00 EST
Symptom Experience, Management, and Outcomes According to Race and Social Determinants Including Genomics, Epigenomics, and Metabolomics (SEMOARS + GEM): an Explanatory Model for Breast Cancer Treatment Disparity. McCall MK, Connolly M, Nugent B, Conley YP, Bender CM, Rosenzweig MQ
J Cancer Educ (Jun 2020)

Even after controlling for stage, comorbidity, age, and insurance status, black women with breast cancer (BC) in the USA have the lowest 5-year survival as compared with all other races for stage-matched disease. One potential cause of this survival difference is the disparity in cancer treatment, evident in many population clinical trials. Specifically, during BC chemotherapy, black women receive less relative dose intensity with more dose reductions and early chemotherapy cessation compared with white women. Symptom incidence, cancer-related distress, and ineffective communication, including the disparity in patient-centeredness of care surrounding patient symptom reporting and clinician assessment, are important factors contributing to racial disparity in dose reduction and early therapy termination. We present an evidence-based overview and an explanatory model for racial disparity in the symptom experience during BC chemotherapy that may lead to a reduction in dose intensity and a subsequent disparity in outcomes. This explanatory model, the Symptom Experience, Management, Outcomes and Adherence according to Race and Social determinants + Genomics Epigenomics and Metabolomics (SEMOARS + GEM), considers essential factors such as social determinants of health, clinician communication, symptoms and symptom management, genomics, epigenomics, and pharmacologic metabolism as contributory factors.]]>
Wed, 31 Dec 1969 19:00:00 EST
Mapping the epigenetic modifications of DNA and RNA. Zhao LY, Song J, Liu Y, Song CX, Yi C
Protein Cell (May 2020)

Over 17 and 160 types of chemical modifications have been identified in DNA and RNA, respectively. The interest in understanding the various biological functions of DNA and RNA modifications has lead to the cutting-edged fields of epigenomics and epitranscriptomics. Developing chemical and biological tools to detect specific modifications in the genome or transcriptome has greatly facilitated their study. Here, we review the recent technological advances in this rapidly evolving field. We focus on high-throughput detection methods and biological findings for these modifications, and discuss questions to be addressed as well. We also summarize third-generation sequencing methods, which enable long-read and single-molecule sequencing of DNA and RNA modification.]]>
Wed, 31 Dec 1969 19:00:00 EST
Learning from methylomes: epigenomic correlates of Populus balsamifera traits based on deep learning models of natural DNA methylation. Champigny MJ, Unda F, Skyba O, Soolanayakanahally RY, Mansfield SD, Campbell MM
Plant Biotechnol J (Jun 2020)

Epigenomes have remarkable potential for the estimation of plant traits. This study tested the hypothesis that natural variation in DNA methylation can be used to estimate industrially important traits in a genetically diverse population of Populus balsamifera L. (balsam poplar) trees grown at two common garden sites. Statistical learning experiments enabled by deep learning models revealed that plant traits in novel genotypes can be modelled transparently using small numbers of methylated DNA predictors. Using this approach, tissue type, a nonheritable attribute, from which DNA methylomes were derived was assigned, and provenance, a purely heritable trait and an element of population structure, was determined. Significant proportions of phenotypic variance in quantitative wood traits, including total biomass (57.5%), wood density (40.9%), soluble lignin (25.3%) and cell wall carbohydrate (mannose: 44.8%) contents, were also explained from natural variation in DNA methylation. Modelling plant traits using DNA methylation can capture tissue-specific epigenetic mechanisms underlying plant phenotypes in natural environments. DNA methylation-based models offer new insight into natural epigenetic influence on plants and can be used as a strategy to validate the identity, provenance or quality of agroforestry products.]]>
Wed, 31 Dec 1969 19:00:00 EST
Logic-based Analysis of Gene Expression Data Predicts Association Between TNF, TGFB1 and EGF Pathways in Basal-like Breast Cancer. Jo K, Santos-Buitrago B, Kim M, Rhee S, Talcott C, Kim S
Methods (May 2020)

For breast cancer, clinically important subtypes are well characterized at the molecular level in terms of gene expression profiles. In addition, signaling pathways in breast cancer have been extensively studied as therapeutic targets due to their roles in tumor growth and metastasis. However, it is challenging to put signaling pathways and gene expression profiles together to characterize biological mechanisms of breast cancer subtypes since many signaling events result from post-translational modifications, rather than gene expression differences. We designed a logic-based computational framework to explain the differences in gene expression profiles among breast cancer subtypes using Pathway Logic and transcriptional network information. Pathway Logic is a rewriting-logic-based formal system for modeling biological pathways including post-translational modifications. Our method demonstrated its utility by constructing subtype-specific path from key receptors (TNFR, TGFBR1 and EGFR) to key transcription factor (TF) regulators (RELA, ATF2, SMAD3 and ELK1) and identifying potential association between pathways via TFs in basal-specific paths, which could provide a novel insight on aggressive breast cancer subtypes. Codes and results are available at http://epigenomics.snu.ac.kr/PL/.]]>
Wed, 31 Dec 1969 19:00:00 EST
From Banding to BAM Files: Genomics Informs Diagnosis and Precision Medicine for Brain Tumors. Dubuc AM
Surg Pathol Clin (Jun 2020)

Tumors of the central nervous system (CNS) have been historically classified according to their morphologic and immunohistochemical features. In 2016, updates to the classification of tumors of the CNS by the World Health Organization revolutionized this paradigm. For the first time, genomic findings, whether whole-arm chromosomal aberrations or single nucleotide variants, represent a necessary and critical component of diagnosis, contributing or superseding histologic findings. These updates stem from decades of technical innovation and genomic discovery. During this time, there has been a dramatic expansion and evolution in clinical genomic assays for these tumors, informing diagnosis and guiding therapeutic management.]]>
Wed, 31 Dec 1969 19:00:00 EST
Loss of Snord116 alters cortical neuronal activity in mice: a pre-clinical investigation of Prader-Willi syndrome. Pace M, Colombi I, Falappa M, Freschi A, Bandarabadi M, Armirotti A, Encarnación BM, Adamantidis AR, Amici R, Cerri M, Chiappalone M, Tucci V
Hum Mol Genet (May 2020)

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder that is characterized by metabolic alteration and sleep abnormalities mostly related to rapid eye movement (REM) sleep disturbances. The disease is caused by genomic imprinting defects that are inherited through the paternal line. Among the genes located in the PWS region on chromosome 15 (15q11-q13), small nucleolar RNA 116 (Snord116) has been previously associated with intrusions of REM sleep into wakefulness in both humans and mice. Here, we further explore sleep regulation of PWS by reporting a study with PWScrm+/p- mouse line, which carries a paternal deletion of Snord116. We focused our study on both macrostructural electrophysiological components of sleep, distributed among REMs and NREMs. Of note, here we study a novel EEG graphoelements of sleep for mouse studies, the well-known spindles. EEG biomarkers are often linked to the functional properties of cortical neurons and can be instrumental in translational studies. Thus, to better understand specific properties, we isolated and characterized the intrinsic activity of cortical neurons using in vitro microelectrode array (MEA). Our results confirm that the loss of Snord116 gene in mice influences specific properties of REM sleep, such as theta rhythms and, for the first time, the organization of REM episodes throughout sleep-wake cycles. Moreover, the analysis of sleep spindles present novel specific phenotype in PWS mice, indicating that a new catalogue of sleep biomarkers can be informative in pre-clinical studies of PWS.]]>
Wed, 31 Dec 1969 19:00:00 EST
PHERES1 Controls Endosperm Gene Imprinting and Seed Development. Wang Y, Jiang H, Wang G
Trends Plant Sci (Jun 2020)

In contrast to mammals, genomic imprinting primarily occurs in the endosperm in flowering plants. Nevertheless, the imprinting drivers and functions of imprinted genes remain poorly understood. Batista et al. identified the type I MADS-box transcription factor (TF) PHERES1 (PHE1) as a key regulator of some imprinted and nonimprinted genes required for endosperm development.]]>
Wed, 31 Dec 1969 19:00:00 EST
Modeling human epigenetic disorders in mice: Beckwith-Wiedemann Syndrome and Silver-Russell Syndrome. Chang S, Bartolomei MS
Dis Model Mech (May 2020)

Genomic imprinting, a phenomenon where the two parental alleles are regulated differently, is observed in mammals, marsupials and a few other species, including seed-bearing plants. Dysregulation of genomic imprinting can cause developmental disorders such as Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS). In this review, we discuss 1) how various (epi)genetic lesions lead to the dysregulation of clinically relevant imprinted loci and 2) how such perturbations may contribute to the developmental defects in BWS and SRS. Given that the regulatory mechanisms of most imprinted clusters are well conserved between mice and humans, numerous mouse models of BWS and SRS have been generated. These mouse models are key to understanding how mutations at imprinted loci result in pathological phenotypes in humans, although there are some limitations. This review focuses on how the biological findings obtained from innovative mouse models explain clinical features of BWS and SRS.]]>
Wed, 31 Dec 1969 19:00:00 EST
Novel visualized quantitative epigenetic imprinted gene biomarkers diagnose the malignancy of ten cancer types. Shen R, Cheng T, Xu C, Yung RC, Bao J, Li X, Yu H, Lu S, Xu H, Wu H, Zhou J, Bu W, Wang X, Si H, Shi P, Zhao P, Liu Y, Deng Y, Zhu Y, Zeng S, Pineda JP, Lin C, Zhou N, Bai C
Clin Epigenetics (May 2020)

Epigenetic alterations are involved in most cancers, but its application in cancer diagnosis is still limited. More practical and intuitive methods to detect the aberrant expressions from clinical samples using highly sensitive biomarkers are needed. In this study, we developed a novel approach in identifying, visualizing, and quantifying the biallelic and multiallelic expressions of an imprinted gene panel associated with cancer status. We evaluated the normal and aberrant expressions measured using the imprinted gene panel to formulate diagnostic models which could accurately distinguish the imprinting differences of normal and benign cases from cancerous tissues for each of the ten cancer types.]]>
Wed, 31 Dec 1969 19:00:00 EST
Epigenomics and transcriptomics analyses of multiple system atrophy brain tissue supports a role for inflammatory processes in disease pathogenesis. Bettencourt C, Piras IS, Foti SC, Talboom J, Miki Y, Lashley T, Balazs R, Viré E, Warner TT, Huentelman MJ, Holton JL
Acta Neuropathol Commun (May 2020)

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Wed, 31 Dec 1969 19:00:00 EST