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Toraason E, Kaletsky R, Murphy C. In vivo neuron-specific expression of C. elegans reprogramming factor orthologs does not alleviate age-related cognitive decline. MICROPUBLICATION BIOLOGY 2024; 2024. [PMID: 39267613 PMCID: PMC11391276 DOI: 10.17912/micropub.biology.001304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2024] [Revised: 08/23/2024] [Accepted: 08/26/2024] [Indexed: 09/15/2024]
Abstract
Overexpression of the OSK(M) (Oct4, Sox2, Klf4, with or without cMyc) pluripotency factors have shown promise in rejuvenating the function of aged neurons. To test whether this intervention could also ameliorate age-associated cognitive decline, we used a doxycycline inducible system to overexpress the C. elegans OSK orthologs specifically in aging C. elegans neurons. We find that OSK does not improve short-term associative memory or extend lifespan and can further disrupt chemotaxis behavior. Taken together, our data suggest that OSK-mediated partial reprogramming may have deleterious effects on post-mitotic neurons that function in cognitive processes.
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Affiliation(s)
- Erik Toraason
- Lewis-Sigler Institute for Integrative Genomics, Princeton University
- Department of Molecular Biology, Princeton University
| | - Rachel Kaletsky
- Lewis-Sigler Institute for Integrative Genomics, Princeton University
- Department of Molecular Biology, Princeton University
| | - Coleen Murphy
- Department of Molecular Biology, Princeton University
- Lewis-Sigler Institute for Integrative Genomics, Princeton University
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2
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Guynes K, Sarre LA, Carrillo-Baltodano AM, Davies BE, Xu L, Liang Y, Martín-Zamora FM, Hurd PJ, de Mendoza A, Martín-Durán JM. Annelid methylomes reveal ancestral developmental and aging-associated epigenetic erosion across Bilateria. Genome Biol 2024; 25:204. [PMID: 39090757 PMCID: PMC11292947 DOI: 10.1186/s13059-024-03346-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 07/23/2024] [Indexed: 08/04/2024] Open
Abstract
BACKGROUND DNA methylation in the form of 5-methylcytosine (5mC) is the most abundant base modification in animals. However, 5mC levels vary widely across taxa. While vertebrate genomes are hypermethylated, in most invertebrates, 5mC concentrates on constantly and highly transcribed genes (gene body methylation; GbM) and, in some species, on transposable elements (TEs), a pattern known as "mosaic". Yet, the role and developmental dynamics of 5mC and how these explain interspecies differences in DNA methylation patterns remain poorly understood, especially in Spiralia, a large clade of invertebrates comprising nearly half of the animal phyla. RESULTS Here, we generate base-resolution methylomes for three species with distinct genomic features and phylogenetic positions in Annelida, a major spiralian phylum. All possible 5mC patterns occur in annelids, from typical invertebrate intermediate levels in a mosaic distribution to hypermethylation and methylation loss. GbM is common to annelids with 5mC, and methylation differences across species are explained by taxon-specific transcriptional dynamics or the presence of intronic TEs. Notably, the link between GbM and transcription decays during development, alongside a gradual and global, age-dependent demethylation in adult stages. Additionally, reducing 5mC levels with cytidine analogs during early development impairs normal embryogenesis and reactivates TEs in the annelid Owenia fusiformis. CONCLUSIONS Our study indicates that global epigenetic erosion during development and aging is an ancestral feature of bilateral animals. However, the tight link between transcription and gene body methylation is likely more important in early embryonic stages, and 5mC-mediated TE silencing probably emerged convergently across animal lineages.
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Affiliation(s)
- Kero Guynes
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, 1030, Austria
| | - Luke A Sarre
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Allan M Carrillo-Baltodano
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Billie E Davies
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Lan Xu
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Yan Liang
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Francisco M Martín-Zamora
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
- Altos Labs, Cambridge, UK
| | - Paul J Hurd
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Alex de Mendoza
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK.
| | - José M Martín-Durán
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK.
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3
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Brown AL, Meiborg AB, Franz-Wachtel M, Macek B, Gordon S, Rog O, Weadick CJ, Werner MS. Characterization of the Pristionchus pacificus "epigenetic toolkit" reveals the evolutionary loss of the histone methyltransferase complex PRC2. Genetics 2024; 227:iyae041. [PMID: 38513719 PMCID: PMC11075575 DOI: 10.1093/genetics/iyae041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 12/04/2023] [Accepted: 03/05/2024] [Indexed: 03/23/2024] Open
Abstract
Comparative approaches have revealed both divergent and convergent paths to achieving shared developmental outcomes. Thus, only through assembling multiple case studies can we understand biological principles. Yet, despite appreciating the conservation-or lack thereof-of developmental networks, the conservation of epigenetic mechanisms regulating these networks is poorly understood. The nematode Pristionchus pacificus has emerged as a model system of plasticity and epigenetic regulation as it exhibits a bacterivorous or omnivorous morph depending on its environment. Here, we determined the "epigenetic toolkit" available to P. pacificus as a resource for future functional work on plasticity, and as a comparison with Caenorhabditis elegans to investigate the conservation of epigenetic mechanisms. Broadly, we observed a similar cast of genes with putative epigenetic function between C. elegans and P. pacificus. However, we also found striking differences. Most notably, the histone methyltransferase complex PRC2 appears to be missing in P. pacificus. We described the deletion/pseudogenization of the PRC2 genes mes-2 and mes-6 and concluded that both were lost in the last common ancestor of P. pacificus and a related species P. arcanus. Interestingly, we observed the enzymatic product of PRC2 (H3K27me3) by mass spectrometry and immunofluorescence, suggesting that a currently unknown methyltransferase has been co-opted for heterochromatin silencing. Altogether, we have provided an inventory of epigenetic genes in P. pacificus to compare with C. elegans. This inventory will enable reverse-genetic experiments related to plasticity and has revealed the first loss of PRC2 in a multicellular organism.
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Affiliation(s)
- Audrey L Brown
- School of Biological Sciences, The University of Utah, Salt Lake City, UT 84112, USA
| | - Adriaan B Meiborg
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
- Faculty of Biosciences, Collaboration for joint PhD degree between EMBL and Heidelberg University, 69120 Heidelberg, Germany
| | | | - Boris Macek
- Proteome Center Tübingen, University of Tübingen, 72074 Tübingen, Germany
| | - Spencer Gordon
- School of Biological Sciences, The University of Utah, Salt Lake City, UT 84112, USA
| | - Ofer Rog
- School of Biological Sciences, The University of Utah, Salt Lake City, UT 84112, USA
| | | | - Michael S Werner
- School of Biological Sciences, The University of Utah, Salt Lake City, UT 84112, USA
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4
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Trexler M, Bányai L, Kerekes K, Patthy L. Evolution of termination codons of proteins and the TAG-TGA paradox. Sci Rep 2023; 13:14294. [PMID: 37653005 PMCID: PMC10471768 DOI: 10.1038/s41598-023-41410-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 08/25/2023] [Indexed: 09/02/2023] Open
Abstract
In most eukaryotes and prokaryotes TGA is used at a significantly higher frequency than TAG as termination codon of protein-coding genes. Although this phenomenon has been recognized several years ago, there is no generally accepted explanation for the TAG-TGA paradox. Our analyses of human mutation data revealed that out of the eighteen sense codons that can give rise to a nonsense codon by single base substitution, the CGA codon is exceptional: it gives rise to the TGA stop codon at an order of magnitude higher rate than the other codons. Here we propose that the TAG-TGA paradox is due to methylation and hypermutabilty of CpG dinucleotides. In harmony with this explanation, we show that the coding genomes of organisms with strong CpG methylation have a significant bias for TGA whereas those from organisms that lack CpG methylation use TGA and TAG termination codons with similar probability.
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Affiliation(s)
- Mária Trexler
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
| | - László Bányai
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
| | - Krisztina Kerekes
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
| | - László Patthy
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary.
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5
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Wilson R, Le Bourgeois M, Perez M, Sarkies P. Fluctuations in chromatin state at regulatory loci occur spontaneously under relaxed selection and are associated with epigenetically inherited variation in C. elegans gene expression. PLoS Genet 2023; 19:e1010647. [PMID: 36862744 PMCID: PMC10013927 DOI: 10.1371/journal.pgen.1010647] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 03/14/2023] [Accepted: 02/01/2023] [Indexed: 03/03/2023] Open
Abstract
Some epigenetic information can be transmitted between generations without changes in the underlying DNA sequence. Changes in epigenetic regulators, termed epimutations, can occur spontaneously and be propagated in populations in a manner reminiscent of DNA mutations. Small RNA-based epimutations occur in C. elegans and persist for around 3-5 generations on average. Here, we explored whether chromatin states also undergo spontaneous change and whether this could be a potential alternative mechanism for transgenerational inheritance of gene expression changes. We compared the chromatin and gene expression profiles at matched time points from three independent lineages of C. elegans propagated at minimal population size. Spontaneous changes in chromatin occurred in around 1% of regulatory regions each generation. Some were heritable epimutations and were significantly enriched for heritable changes in expression of nearby protein-coding genes. Most chromatin-based epimutations were short-lived but a subset had longer duration. Genes subject to long-lived epimutations were enriched for multiple components of xenobiotic response pathways. This points to a possible role for epimutations in adaptation to environmental stressors.
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Affiliation(s)
- Rachel Wilson
- MRC London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Imperial College London, London, United Kingdom.,Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | | | - Marcos Perez
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Peter Sarkies
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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6
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Skvortsova K, Bertrand S, Voronov D, Duckett PE, Ross SE, Magri MS, Maeso I, Weatheritt RJ, Gómez Skarmeta JL, Arnone MI, Escriva H, Bogdanovic O. Active DNA demethylation of developmental cis-regulatory regions predates vertebrate origins. SCIENCE ADVANCES 2022; 8:eabn2258. [PMID: 36459547 PMCID: PMC10936051 DOI: 10.1126/sciadv.abn2258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 10/19/2022] [Indexed: 06/17/2023]
Abstract
DNA methylation [5-methylcytosine (5mC)] is a repressive gene-regulatory mark required for vertebrate embryogenesis. Genomic 5mC is tightly regulated through the action of DNA methyltransferases, which deposit 5mC, and ten-eleven translocation (TET) enzymes, which participate in its active removal through the formation of 5-hydroxymethylcytosine (5hmC). TET enzymes are essential for mammalian gastrulation and activation of vertebrate developmental enhancers; however, to date, a clear picture of 5hmC function, abundance, and genomic distribution in nonvertebrate lineages is lacking. By using base-resolution 5mC and 5hmC quantification during sea urchin and lancelet embryogenesis, we shed light on the roles of nonvertebrate 5hmC and TET enzymes. We find that these invertebrate deuterostomes use TET enzymes for targeted demethylation of regulatory regions associated with developmental genes and show that the complement of identified 5hmC-regulated genes is conserved to vertebrates. This work demonstrates that active 5mC removal from regulatory regions is a common feature of deuterostome embryogenesis suggestive of an unexpected deep conservation of a major gene-regulatory module.
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Affiliation(s)
- Ksenia Skvortsova
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
- St. Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Stephanie Bertrand
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, Banyuls-sur-Mer, France
| | - Danila Voronov
- Biology and Evolution of Marine Organisms (BEOM), Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Paul E. Duckett
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
| | - Samuel E. Ross
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
- St. Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, Australia
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 22, Australia
| | - Marta Silvia Magri
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, Spain
| | - Ignacio Maeso
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, Spain
| | - Robert J. Weatheritt
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
- EMBL Australia, Garvan Institute of Medical Research, Sydney, Australia
| | - Jose Luis Gómez Skarmeta
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, Spain
| | - Maria Ina Arnone
- Biology and Evolution of Marine Organisms (BEOM), Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Hector Escriva
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, Banyuls-sur-Mer, France
| | - Ozren Bogdanovic
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 22, Australia
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, Spain
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7
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Rittiner J, Cumaran M, Malhotra S, Kantor B. Therapeutic modulation of gene expression in the disease state: Treatment strategies and approaches for the development of next-generation of the epigenetic drugs. Front Bioeng Biotechnol 2022; 10:1035543. [PMID: 36324900 PMCID: PMC9620476 DOI: 10.3389/fbioe.2022.1035543] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 10/05/2022] [Indexed: 11/18/2022] Open
Abstract
Epigenetic dysregulation is an important determinant of many pathological conditions and diseases. Designer molecules that can specifically target endogenous DNA sequences provide a means to therapeutically modulate gene function. The prokaryote-derived CRISPR/Cas editing systems have transformed our ability to manipulate the expression program of genes through specific DNA and RNA targeting in living cells and tissues. The simplicity, utility, and robustness of this technology have revolutionized epigenome editing for research and translational medicine. Initial success has inspired efforts to discover new systems for targeting and manipulating nucleic acids on the epigenetic level. The evolution of nuclease-inactive and RNA-targeting Cas proteins fused to a plethora of effector proteins to regulate gene expression, epigenetic modifications and chromatin interactions opened up an unprecedented level of possibilities for the development of "next-generation" gene therapy therapeutics. The rational design and construction of different types of designer molecules paired with viral-mediated gene-to-cell transfers, specifically using lentiviral vectors (LVs) and adeno-associated vectors (AAVs) are reviewed in this paper. Furthermore, we explore and discuss the potential of these molecules as therapeutic modulators of endogenous gene function, focusing on modulation by stable gene modification and by regulation of gene transcription. Notwithstanding the speedy progress of CRISPR/Cas-based gene therapy products, multiple challenges outlined by undesirable off-target effects, oncogenicity and other virus-induced toxicities could derail the successful translation of these new modalities. Here, we review how CRISPR/Cas-based gene therapy is translated from research-grade technological system to therapeutic modality, paying particular attention to the therapeutic flow from engineering sophisticated genome and epigenome-editing transgenes to delivery vehicles throughout efficient and safe manufacturing and administration of the gene therapy regimens. In addition, the potential solutions to some of the obstacles facing successful CRISPR/Cas utility in the clinical research are discussed in this review. We believe, that circumventing these challenges will be essential for advancing CRISPR/Cas-based tools towards clinical use in gene and cell therapies.
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Affiliation(s)
- Joseph Rittiner
- Department of Neurobiology, Duke University Medical Center, Durham, NC, United States
- Viral Vector Core, Duke University Medical Center, Durham, NC, United States
- Duke Center for Advanced Genomic Technologies, Durham, NC, United States
| | - Mohanapriya Cumaran
- Department of Neurobiology, Duke University Medical Center, Durham, NC, United States
- Viral Vector Core, Duke University Medical Center, Durham, NC, United States
- Duke Center for Advanced Genomic Technologies, Durham, NC, United States
| | - Sahil Malhotra
- Department of Neurobiology, Duke University Medical Center, Durham, NC, United States
- Viral Vector Core, Duke University Medical Center, Durham, NC, United States
- Duke Center for Advanced Genomic Technologies, Durham, NC, United States
| | - Boris Kantor
- Department of Neurobiology, Duke University Medical Center, Durham, NC, United States
- Viral Vector Core, Duke University Medical Center, Durham, NC, United States
- Duke Center for Advanced Genomic Technologies, Durham, NC, United States
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8
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Chapelle V, Silvestre F. Population Epigenetics: The Extent of DNA Methylation Variation in Wild Animal Populations. EPIGENOMES 2022; 6:31. [PMID: 36278677 PMCID: PMC9589984 DOI: 10.3390/epigenomes6040031] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/17/2022] Open
Abstract
Population epigenetics explores the extent of epigenetic variation and its dynamics in natural populations encountering changing environmental conditions. In contrast to population genetics, the basic concepts of this field are still in their early stages, especially in animal populations. Epigenetic variation may play a crucial role in phenotypic plasticity and local adaptation as it can be affected by the environment, it is likely to have higher spontaneous mutation rate than nucleotide sequences do, and it may be inherited via non-mendelian processes. In this review, we aim to bring together natural animal population epigenetic studies to generate new insights into ecological epigenetics and its evolutionary implications. We first provide an overview of the extent of DNA methylation variation and its autonomy from genetic variation in wild animal population. Second, we discuss DNA methylation dynamics which create observed epigenetic population structures by including basic population genetics processes. Then, we highlight the relevance of DNA methylation variation as an evolutionary mechanism in the extended evolutionary synthesis. Finally, we suggest new research directions by highlighting gaps in the knowledge of the population epigenetics field. As for our results, DNA methylation diversity was found to reveal parameters that can be used to characterize natural animal populations. Some concepts of population genetics dynamics can be applied to explain the observed epigenetic structure in natural animal populations. The set of recent advancements in ecological epigenetics, especially in transgenerational epigenetic inheritance in wild animal population, might reshape the way ecologists generate predictive models of the capacity of organisms to adapt to changing environments.
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Affiliation(s)
- Valentine Chapelle
- Laboratory of Evolutionary and Adaptive Physiology, Institute of Life, Earth, and Environment, University of Namur, 61 Rue de Bruxelles, 5000 Namur, Belgium
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9
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Zhao L, Zhou Q, He L, Deng L, Lozano-Duran R, Li G, Zhu JK. DNA methylation underpins the epigenomic landscape regulating genome transcription in Arabidopsis. Genome Biol 2022; 23:197. [PMID: 36127735 PMCID: PMC9487137 DOI: 10.1186/s13059-022-02768-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 09/08/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It is challenging to determine the effect of DNA methylation on the epigenetic landscape and the function in higher organisms due to the lack of DNA methylation-free mutants. RESULTS Here, the analysis of a recently generated Arabidopsis mutant completely devoid of DNA methylation reveals that DNA methylation underpins the genome-wide landscape of histone modifications. Complete loss of DNA methylation causes an upheaval of the histone modification landscape, including complete loss of H3K9me2 and widespread redistribution of active and H3K27me3 histone marks, mostly owing to the role of DNA methylation in initiating H3K9me2 deposition and excluding active marks and repressive mark H3K27me3; CG and non-CG methylation can act independently at some genomic regions while they act cooperatively at many other regions. The transcriptional reprogramming upon loss of all DNA methylation correlates with the extensive redistribution or switches of the examined histone modifications. Histone modifications retained or gained in the DNA methylation-free mutant serve as DNA methylation-independent transcriptional regulatory signals: active marks promote genome transcription, whereas the repressive mark H3K27me3 compensates for the lack of DNA hypermethylation/H3K9me2 at multiple transposon families. CONCLUSIONS Our results show that an intact DNA methylome constitutes the scaffolding of the epigenomic landscape in Arabidopsis and is critical for controlled genome transcription and ultimately for proper growth and development.
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Affiliation(s)
- Lun Zhao
- National Key Laboratory of Crop Genetic Improvement, National Engineering Research Center of Rapeseed, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Qiangwei Zhou
- National Key Laboratory of Crop Genetic Improvement, National Engineering Research Center of Rapeseed, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Li He
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Li Deng
- National Key Laboratory of Crop Genetic Improvement, National Engineering Research Center of Rapeseed, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Rosa Lozano-Duran
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
- Department of Plant Biochemistry, Centre for Plant Molecular Biology (ZMBP), Eberhard Karls University, D-72076, Tübingen, Germany
| | - Guoliang Li
- National Key Laboratory of Crop Genetic Improvement, National Engineering Research Center of Rapeseed, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China.
- Hubei Key Laboratory of Agricultural Bioinformatics and Hubei Engineering Technology Research Center of Agricultural Big Data, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China.
- Institute of Advanced Biotechnology and School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
- Center for Advanced Bioindustry Technologies, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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10
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Macchi F, Edsinger E, Sadler KC. Epigenetic machinery is functionally conserved in cephalopods. BMC Biol 2022; 20:202. [PMID: 36104784 PMCID: PMC9476566 DOI: 10.1186/s12915-022-01404-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 09/07/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Epigenetic regulatory mechanisms are divergent across the animal kingdom, yet these mechanisms are not well studied in non-model organisms. Unique features of cephalopods make them attractive for investigating behavioral, sensory, developmental, and regenerative processes, and recent studies have elucidated novel features of genome organization and gene and transposon regulation in these animals. However, it is not known how epigenetics regulates these interesting cephalopod features. We combined bioinformatic and molecular analysis of Octopus bimaculoides to investigate the presence and pattern of DNA methylation and examined the presence of DNA methylation and 3 histone post-translational modifications across tissues of three cephalopod species. RESULTS We report a dynamic expression profile of the genes encoding conserved epigenetic regulators, including DNA methylation maintenance factors in octopus tissues. Levels of 5-methyl-cytosine in multiple tissues of octopus, squid, and bobtail squid were lower compared to vertebrates. Whole genome bisulfite sequencing of two regions of the brain and reduced representation bisulfite sequencing from a hatchling of O. bimaculoides revealed that less than 10% of CpGs are methylated in all samples, with a distinct pattern of 5-methyl-cytosine genome distribution characterized by enrichment in the bodies of a subset of 14,000 genes and absence from transposons. Hypermethylated genes have distinct functions and, strikingly, many showed similar expression levels across tissues while hypomethylated genes were silenced or expressed at low levels. Histone marks H3K27me3, H3K9me3, and H3K4me3 were detected at different levels across tissues of all species. CONCLUSIONS Our results show that the DNA methylation and histone modification epigenetic machinery is conserved in cephalopods, and that, in octopus, 5-methyl-cytosine does not decorate transposable elements, but is enriched on the gene bodies of highly expressed genes and could cooperate with the histone code to regulate tissue-specific gene expression.
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Affiliation(s)
- Filippo Macchi
- Program in Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
| | - Eric Edsinger
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Kirsten C Sadler
- Program in Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates.
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11
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DNA Methyltransferases: From Evolution to Clinical Applications. Int J Mol Sci 2022; 23:ijms23168994. [PMID: 36012258 PMCID: PMC9409253 DOI: 10.3390/ijms23168994] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 07/28/2022] [Accepted: 08/02/2022] [Indexed: 11/18/2022] Open
Abstract
DNA methylation is an epigenetic mark that living beings have used in different environments. The MTases family catalyzes DNA methylation. This process is conserved from archaea to eukaryotes, from fertilization to every stage of development, and from the early stages of cancer to metastasis. The family of DNMTs has been classified into DNMT1, DNMT2, and DNMT3. Each DNMT has been duplicated or deleted, having consequences on DNMT structure and cellular function, resulting in a conserved evolutionary reaction of DNA methylation. DNMTs are conserved in the five kingdoms of life: bacteria, protists, fungi, plants, and animals. The importance of DNMTs in whether methylate or not has a historical adaptation that in mammals has been discovered in complex regulatory mechanisms to develop another padlock to genomic insurance stability. The regulatory mechanisms that control DNMTs expression are involved in a diversity of cell phenotypes and are associated with pathologies transcription deregulation. This work focused on DNA methyltransferases, their biology, functions, and new inhibitory mechanisms reported. We also discuss different approaches to inhibit DNMTs, the use of non-coding RNAs and nucleoside chemical compounds in recent studies, and their importance in biological, clinical, and industry research.
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12
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Arsala D, Wu X, Yi SV, Lynch JA. Dnmt1a is essential for gene body methylation and the regulation of the zygotic genome in a wasp. PLoS Genet 2022; 18:e1010181. [PMID: 35522715 PMCID: PMC9075658 DOI: 10.1371/journal.pgen.1010181] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/01/2022] [Indexed: 11/19/2022] Open
Abstract
Gene body methylation (GBM) is an ancestral mode of DNA methylation whose role in development has been obscured by the more prominent roles of promoter and CpG island methylation. The wasp Nasonia vitripennis has little promoter and CpG island methylation, yet retains strong GBM, making it an excellent model for elucidating the roles of GBM. Here we show that N. vitripennis DNA methyltransferase 1a (Nv-Dnmt1a) knockdown leads to failures in cellularization and gastrulation of the embryo. Both of these disrupted events are hallmarks of the maternal-zygotic transition (MZT) in insects. Analysis of the embryonic transcriptome and methylome revealed strong reduction of GBM and widespread disruption of gene expression during embryogenesis after Nv-Dnmt1a knockdown. Strikingly, there was a strong correlation between loss of GBM and reduced gene expression in thousands of methylated loci, consistent with the hypothesis that GBM directly facilitates high levels of transcription. We propose that lower expression levels of methylated genes due to reduced GBM is the crucial direct effect of Nv-Dnmt1 knockdown. Subsequently, the disruption of methylated genes leads to downstream dysregulation of the MZT, culminating in developmental failure at gastrulation.
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Affiliation(s)
- Deanna Arsala
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Ecology & Evolution, University of Chicago, Chicago, Illinois, United States of America
| | - Xin Wu
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Soojin V. Yi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Jeremy A. Lynch
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
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13
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Takahashi Y, Shoura M, Fire A, Morishita S. Context-dependent DNA polymerization effects can masquerade as DNA modification signals. BMC Genomics 2022; 23:249. [PMID: 35361121 PMCID: PMC8973881 DOI: 10.1186/s12864-022-08471-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 03/15/2022] [Indexed: 11/23/2022] Open
Abstract
Background Single molecule measurements of DNA polymerization kinetics provide a sensitive means to detect both secondary structures in DNA and deviations from primary chemical structure as a result of modified bases. In one approach to such analysis, deviations can be inferred by monitoring the behavior of DNA polymerase using single-molecule, real-time sequencing with zero-mode waveguide. This approach uses a Single Molecule Real Time (SMRT)-sequencing measurement of time between fluorescence pulse signals from consecutive nucleosides incorporated during DNA replication, called the interpulse duration (IPD). Results In this paper we present an analysis of loci with high IPDs in two genomes, a bacterial genome (E. coli) and a eukaryotic genome (C. elegans). To distinguish the potential effects of DNA modification on DNA polymerization speed, we paired an analysis of native genomic DNA with whole-genome amplified (WGA) material in which DNA modifications were effectively removed. Adenine modification sites for E. coli are known and we observed the expected IPD shifts at these sites in the native but not WGA samples. For C. elegans, such differences were not observed. Instead, we found a number of novel sequence contexts where IPDs were raised relative to the average IPDs for each of the four nucleotides, but for which the raised IPD was present in both native and WGA samples. Conclusion The latter results argue strongly against DNA modification as the underlying driver for high IPD segments for C. elegans, and provide a framework for separating effects of DNA modification from context-dependent DNA polymerase kinetic patterns inherent in underlying DNA sequence for a complex eukaryotic genome. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08471-2.
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Affiliation(s)
- Yusuke Takahashi
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
| | - Massa Shoura
- Departments of Pathology and Genetics, School of Medicine, Stanford University, Stanford, CA, USA
| | - Andrew Fire
- Departments of Pathology and Genetics, School of Medicine, Stanford University, Stanford, CA, USA.
| | - Shinichi Morishita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan.
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14
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Katju V, Konrad A, Deiss TC, Bergthorsson U. Mutation rate and spectrum in obligately outcrossing Caenorhabditis elegans mutation accumulation lines subjected to RNAi-induced knockdown of the mismatch repair gene msh-2. G3 GENES|GENOMES|GENETICS 2022; 12:6407146. [PMID: 34849777 PMCID: PMC8727991 DOI: 10.1093/g3journal/jkab364] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 10/13/2021] [Indexed: 01/09/2023]
Abstract
DNA mismatch repair (MMR), an evolutionarily conserved repair pathway shared by prokaryotic and eukaryotic species alike, influences molecular evolution by detecting and correcting mismatches, thereby protecting genetic fidelity, reducing the mutational load, and preventing lethality. Herein we conduct the first genome-wide evaluation of the alterations to the mutation rate and spectrum under impaired activity of the MutSα homolog, msh-2, in Caenorhabditis elegans male–female fog-2(lf) lines. We performed mutation accumulation (MA) under RNAi-induced knockdown of msh-2 for up to 50 generations, followed by next-generation sequencing of 19 MA lines and the ancestral control. msh-2 impairment in the male–female background substantially increased the frequency of nuclear base substitutions (∼23×) and small indels (∼328×) relative to wildtype hermaphrodites. However, we observed no increase in the mutation rates of mtDNA, and copy-number changes of single-copy genes. There was a marked increase in copy-number variation of rDNA genes under MMR impairment. In C. elegans, msh-2 repairs transitions more efficiently than transversions and increases the AT mutational bias relative to wildtype. The local sequence context, including sequence complexity, G + C-content, and flanking bases influenced the mutation rate. The X chromosome exhibited lower substitution and higher indel rates than autosomes, which can either result from sex-specific mutation rates or a nonrandom distribution of mutable sites between chromosomes. Provided the observed difference in mutational pattern is mostly due to MMR impairment, our results indicate that the specificity of MMR varies between taxa, and is more efficient in detecting and repairing small indels in eukaryotes relative to prokaryotes.
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Affiliation(s)
- Vaishali Katju
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77845, USA
| | - Anke Konrad
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77845, USA
- Faculdade de Ciência da Universidade de Lisboa (FCUL), CE3C—Centre for Ecology, Evolution and Environmental Changes, 1749-016 Lisboa, Portugal
| | - Thaddeus C Deiss
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77845, USA
| | - Ulfar Bergthorsson
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77845, USA
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15
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Lister-Shimauchi EH, Dinh M, Maddox P, Ahmed S. Gametes deficient for Pot1 telomere binding proteins alter levels of telomeric foci for multiple generations. Commun Biol 2021; 4:158. [PMID: 33542458 PMCID: PMC7862594 DOI: 10.1038/s42003-020-01624-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 12/15/2020] [Indexed: 11/20/2022] Open
Abstract
Deficiency for telomerase results in transgenerational shortening of telomeres. However, telomeres have no known role in transgenerational epigenetic inheritance. C. elegans Protection Of Telomeres 1 (Pot1) proteins form foci at the telomeres of germ cells that disappear at fertilization and gradually accumulate during development. We find that gametes from mutants deficient for Pot1 proteins alter levels of telomeric foci for multiple generations. Gametes from pot-2 mutants give rise to progeny with abundant POT-1::mCherry and mNeonGreen::POT-2 foci throughout development, which persists for six generations. In contrast, gametes from pot-1 mutants or pot-1; pot-2 double mutants induce diminished Pot1 foci for several generations. Deficiency for MET-2, SET-25, or SET-32 methyltransferases, which promote heterochromatin formation, results in gametes that induce diminished Pot1 foci for several generations. We propose that C. elegans POT-1 may interact with H3K9 methyltransferases during pot-2 mutant gametogenesis to induce a persistent form of transgenerational epigenetic inheritance that causes constitutively high levels of heterochromatic Pot1 foci.
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Affiliation(s)
- Evan H Lister-Shimauchi
- Department of Genetics, University of North Carolina, Chapel Hill, NC, 27599, USA.
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA.
| | - Michael Dinh
- Department of Genetics, University of North Carolina, Chapel Hill, NC, 27599, USA
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Paul Maddox
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, 27599, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Shawn Ahmed
- Department of Genetics, University of North Carolina, Chapel Hill, NC, 27599, USA.
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, 27599, USA.
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, 27599, USA.
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16
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Yagound B, Remnant EJ, Buchmann G, Oldroyd BP. Intergenerational transfer of DNA methylation marks in the honey bee. Proc Natl Acad Sci U S A 2020; 117:32519-32527. [PMID: 33257552 PMCID: PMC7768778 DOI: 10.1073/pnas.2017094117] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The evolutionary significance of epigenetic inheritance is controversial. While epigenetic marks such as DNA methylation can affect gene function and change in response to environmental conditions, their role as carriers of heritable information is often considered anecdotal. Indeed, near-complete DNA methylation reprogramming, as occurs during mammalian embryogenesis, is a major hindrance for the transmission of nongenetic information between generations. Yet it remains unclear how general DNA methylation reprogramming is across the tree of life. Here we investigate the existence of epigenetic inheritance in the honey bee. We studied whether fathers can transfer epigenetic information to their daughters through DNA methylation. We performed instrumental inseminations of queens, each with four different males, retaining half of each male's semen for whole genome bisulfite sequencing. We then compared the methylation profile of each father's somatic tissue and semen with the methylation profile of his daughters. We found that DNA methylation patterns were highly conserved between tissues and generations. There was a much greater similarity of methylomes within patrilines (i.e., father-daughter subfamilies) than between patrilines in each colony. Indeed, the samples' methylomes consistently clustered by patriline within colony. Samples from the same patriline had twice as many shared methylated sites and four times fewer differentially methylated regions compared to samples from different patrilines. Our findings indicate that there is no DNA methylation reprogramming in bees and, consequently, that DNA methylation marks are stably transferred between generations. This points to a greater evolutionary potential of the epigenome in invertebrates than there is in mammals.
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Affiliation(s)
- Boris Yagound
- Behaviour, Ecology and Evolution Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia;
| | - Emily J Remnant
- Behaviour, Ecology and Evolution Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Gabriele Buchmann
- Behaviour, Ecology and Evolution Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Benjamin P Oldroyd
- Behaviour, Ecology and Evolution Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
- Wissenschaftskolleg zu Berlin, 14193 Berlin, Germany
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17
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Genome-wide identification and transcriptional modulation of histone variants and modification related genes in the low pH-exposed marine rotifer Brachionus koreanus. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 36:100748. [PMID: 33032078 DOI: 10.1016/j.cbd.2020.100748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/05/2020] [Accepted: 09/18/2020] [Indexed: 11/22/2022]
Abstract
Histone modification is considered to be a major epigenetic control mechanism. These modifications (e.g. acetylation, phosphorylation, and methylation) may affect the interaction of histones with DNA and/or regulate DNA-based processes (e.g., recombination, repair, replication, and transcription) and chromatin remodeling complexes. Despite their significance in metazoan life and evolution, few studies have been conducted to identify genes undergoing epigenetic control modification in aquatic invertebrates. In this study, we identified whole core histones (70 total genes) and post-translational modification (PTM) histone genes (63 total genes) in the marine rotifer Brachionus koreanus through whole-genome analysis, and annotated them according to the human nomenclature. Notably, upon comparative analysis of cis-regulatory motif sequences, we found that B. koreanus core histone protein structures were similar to those of mammals. Furthermore, to examine the effect of parental low pH stress on the offspring's epigenetic regulation, we investigated the expression of PTM genes in two generations of B. koreanus exposed to low pH conditions. Given that the B. koreanus genome does not possess DNA methyltransferase 1 and 3 genes, we concluded that histone genes could be involved as an important epigenetic mechanism in B. koreanus. Therefore, the histone-associated genes identified in this study could be useful for ecotoxicological studies and facilitate the application of chromatin immunoprecipitation sequencing using high-throughput DNA sequencing based on the genome-wide identification of transcription factor binding sites in rotifers.
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18
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Arsenite-induced transgenerational glycometabolism is associated with up-regulation of H3K4me2 via inhibiting spr-5 in caenorhabditis elegans. Toxicol Lett 2020; 326:11-17. [PMID: 32142838 DOI: 10.1016/j.toxlet.2020.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 11/23/2022]
Abstract
Arsenic (As) is a toxic element that is highly abundant in the environment. However, there has not been sufficient research into the mechanisms of arsenic-induced transgenerational effects. In biomedical and environmental toxicology research field, C. elegans are often used as the ideal model. In this study, F0 generation animals were cultured with arsenite, while subsequent generations animals (F1 - F6) were cultured in the absence of arsenic. Experiments were performed to examine the transgenerational glycometabolism and the associated mechanisms in all seven generations (F0 - F6) of C. elegans. Results show that arsenite exposure increased total glucose content but reduced glucose metabolites in F0 generation C. elegans. The total glucose content was also elevated in subsequent generations probably due to transgenerational downregulation of fgt-1. In addition, arsenite exposure induced transgenerational downregulation of histone demethyltransferase spr-5 and elevated histone dimethylation in F0 generation. This study highlights that single generation exposure to arsenite causes transgenerational changes in glycometabolism in C. elegans, which may be caused by downregulation of spr-5 and elevation of H3K4me2.
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19
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DNA Methylation Changes Induced by Cold in Psychrophilic and Psychrotolerant Naganishia Yeast Species. Microorganisms 2020; 8:microorganisms8020296. [PMID: 32093408 PMCID: PMC7074839 DOI: 10.3390/microorganisms8020296] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/11/2020] [Accepted: 02/14/2020] [Indexed: 12/18/2022] Open
Abstract
The involvement of DNA methylation in the response to cold stress of two different yeast species (Naganishia antarctica, psychrophilic, and Naganishia albida, psychrotolerant), exhibiting different temperature aptitudes, has been studied. Consecutive incubations at respective optimum temperatures, at 4 °C (cold stress) and at optimum temperatures again, were performed. After Methylation Sensitive Amplified Polymorphism (MSAP) fingerprints a total of 550 and 423 clear and reproducible fragments were amplified from N. antarctica and N. albida strains, respectively. The two Naganishia strains showed a different response in terms of level of DNA methylation during cold stress and recovery from cold stress. The percentage of total methylated fragments in psychrophilic N. antarctica did not show any significant change. On the contrary, the methylation of psychrotolerant N. albida exhibited a nonsignificant increase during the incubation at 4 °C and continued during the recovery step, showing a significant difference if compared with control condition, resembling an uncontrolled response to cold stress. A total of 12 polymorphic fragments were selected, cloned, and sequenced. Four fragments were associated to genes encoding for elongation factor G and for chitin synthase export chaperon. To the best of our knowledge, this is the first study on DNA methylation in the response to cold stress carried out by comparing a psychrophilic and a psychrotolerant yeast species.
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20
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Godwin J, Farrona S. Plant Epigenetic Stress Memory Induced by Drought: A Physiological and Molecular Perspective. Methods Mol Biol 2020; 2093:243-259. [PMID: 32088901 DOI: 10.1007/978-1-0716-0179-2_17] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Drought stress is one of the most common stresses encountered by crops and other plants and leads to significant productivity losses. It commonly happens that drought stress occurs more than once during the plant's life cycle. Plants suffering from drought stress can adapt their life strategies to acclimate and survive in many different ways. Interestingly, some plants have evolved a stress response strategy referred to as stress memory which leads to an enhanced response the next time the stress is encountered. The acquisition of stress memory leads to a reprogrammed transcriptional response during subsequent stress and subsequent changes both at the physiological and molecular level. Recent advances in understanding chromatin dynamics have demonstrated the involvement of chromatin modifications, especially histone marks, associated with drought stress-responsive memory genes and subsequent enhanced transcriptional responses to repeated drought stress. In this chapter, we describe recent progress in this area and summarize techniques for the study of plant epigenetic responses to stress, including the roles of ABA and transcription factors in superinduced transcriptional activation during recurrent drought stress. We also review the possible use of seed priming to induce stress memory later in the plant life cycle. Finally, we discuss the potential implications of understanding the epigenetic mechanisms involved in plant stress memory for future applications in crop improvement and drought resistance.
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Affiliation(s)
- James Godwin
- Plant and AgriBiosciences Research Centre, Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Sara Farrona
- Plant and AgriBiosciences Research Centre, Ryan Institute, National University of Ireland Galway, Galway, Ireland.
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21
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de Mendoza A, Lister R, Bogdanovic O. Evolution of DNA Methylome Diversity in Eukaryotes. J Mol Biol 2019:S0022-2836(19)30659-X. [PMID: 31726061 DOI: 10.1016/j.jmb.2019.11.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 12/23/2022]
Abstract
Cytosine DNA methylation (5mC) is a widespread base modification in eukaryotic genomes with critical roles in transcriptional regulation. In recent years, our understanding of 5mC has changed because of advances in 5mC detection techniques that allow mapping of this mark on the whole genome scale. Profiling DNA methylomes from organisms across the eukaryotic tree of life has reshaped our views on the evolution of 5mC. In this review, we explore the macroevolution of 5mC in major eukaryotic groups, and then focus on recent advances made in animals. Genomic 5mC patterns as well as the mechanisms of 5mC deposition tend to be evolutionary labile across large phylogenetic distances; however, some common patterns are starting to emerge. Within the animal kingdom, 5mC diversity has proven to be much greater than anticipated. For example, a previously held common view that genome hypermethylation is a trait exclusive to vertebrates has recently been challenged. Also, data from genome-wide studies are starting to yield insights into the potential roles of 5mC in invertebrate cis regulation. Here we provide an evolutionary perspective of both the well-known and enigmatic roles of 5mC across the eukaryotic tree of life.
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Affiliation(s)
- Alex de Mendoza
- ARC CoE Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia; Harry Perkins Institute of Medical Research, Perth, WA 6009, Australia.
| | - Ryan Lister
- ARC CoE Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia; Harry Perkins Institute of Medical Research, Perth, WA 6009, Australia
| | - Ozren Bogdanovic
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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22
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Abstract
The idea that epigenetic determinants such as DNA methylation, histone modifications or RNA can be passed to the next generation through meiotic products (gametes) is long standing. Such meiotic epigenetic inheritance (MEI) is fairly common in yeast, plants and nematodes, but its extent in mammals has been much debated. Advances in genomics techniques are now driving the profiling of germline and zygotic epigenomes, thereby improving our understanding of MEI in diverse species. Whereas the role of DNA methylation in MEI remains unclear, insights from genome-wide studies suggest that a previously underappreciated fraction of mammalian genomes bypass epigenetic reprogramming during development. Notably, intergenerational inheritance of histone modifications, tRNA fragments and microRNAs can affect gene regulation in the offspring. It is important to note that MEI in mammals rarely constitutes transgenerational epigenetic inheritance (TEI), which spans multiple generations. In this Review, we discuss the examples of MEI in mammals, including mammalian epigenome reprogramming, and the molecular mechanisms of MEI in vertebrates in general. We also discuss the implications of the inheritance of histone modifications and small RNA for embryogenesis in metazoans, with a particular focus on insights gained from genome-wide studies.
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23
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Abstract
Identifying and validating molecular targets of interventions that extend the human health span and lifespan has been difficult, as most clinical biomarkers are not sufficiently representative of the fundamental mechanisms of ageing to serve as their indicators. In a recent breakthrough, biomarkers of ageing based on DNA methylation data have enabled accurate age estimates for any tissue across the entire life course. These 'epigenetic clocks' link developmental and maintenance processes to biological ageing, giving rise to a unified theory of life course. Epigenetic biomarkers may help to address long-standing questions in many fields, including the central question: why do we age?
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24
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Liu K, Lei M, Wu Z, Gan B, Cheng H, Li Y, Min J. Structural analyses reveal that MBD3 is a methylated CG binder. FEBS J 2019; 286:3240-3254. [PMID: 30980593 DOI: 10.1111/febs.14850] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/19/2019] [Accepted: 04/11/2019] [Indexed: 12/17/2022]
Abstract
The MBD3, a methyl-CpG-binding domain (MBD)-containing protein, is a core subunit of the Mi-2/NuRD complex. Recent reports show that MBD3 recognizes both methylated CG (mCG)- and hydroxymethylated CG (hmCG)-containing DNA, with a preference for hmCG. However, whether the MBD3-MBD indeed has methyl-CG-binding ability is controversial. In this study, we provided the structural basis to support the ability of MBD3-MBD to bind mCG-containing DNA. We found that the MBD3-MBD bound to mCG-containing DNA through two conserved arginine fingers, and preferentially bound to mCG over hmCG, similar to other methyl-CpG-binding MBD proteins. Compared to its closest homolog MBD2, the tyrosine-to-phenylalanine substitution at Phe34 of MBD3 is responsible for a weaker mCG DNA binding ability. Based on the complex structure of MBD3-MBD with a nonpalindromic AmCGC DNA, we suggest that all the mCG-binding MBD domains can recognize mCG-containing DNA without orientation selectivity, consistent with our observations that the sequences outside the mCG dinucleotide do not affect mCG DNA binding significantly. DNA cytosine methylation is evolutionarily conserved in most metazoans, and most invertebrates have only one MBD gene, MBD2/3. We also looked into the mCG DNA binding ability of some invertebrates MBD2/3 and found that the conserved arginine fingers and a conserved structural fold are required for methylated DNA binding by MBD2/3-MBDs in invertebrates. Hence, our results demonstrate that mCG-binding arginine fingers embedded into a conserved structural fold are essential structural features for MBD2/3s binding to methylated DNA among metazoans.
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Affiliation(s)
- Ke Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China.,Structural Genomics Consortium, University of Toronto, Canada
| | - Ming Lei
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China.,Structural Genomics Consortium, University of Toronto, Canada
| | - Zhibin Wu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Bing Gan
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Harry Cheng
- Structural Genomics Consortium, University of Toronto, Canada
| | - Yanjun Li
- Structural Genomics Consortium, University of Toronto, Canada
| | - Jinrong Min
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China.,Structural Genomics Consortium, University of Toronto, Canada.,Department of Physiology, University of Toronto, Canada
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25
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Histone Methylation and Memory of Environmental Stress. Cells 2019; 8:cells8040339. [PMID: 30974922 PMCID: PMC6523599 DOI: 10.3390/cells8040339] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/05/2019] [Accepted: 04/07/2019] [Indexed: 02/07/2023] Open
Abstract
Cellular adaptation to environmental stress relies on a wide range of tightly controlled regulatory mechanisms, including transcription. Changes in chromatin structure and organization accompany the transcriptional response to stress, and in some cases, can impart memory of stress exposure to subsequent generations through mechanisms of epigenetic inheritance. In the budding yeast Saccharomyces cerevisiae, histone post-translational modifications, and in particular histone methylation, have been shown to confer transcriptional memory of exposure to environmental stress conditions through mitotic divisions. Recent evidence from Caenorhabditis elegans also implicates histone methylation in transgenerational inheritance of stress responses, suggesting a more widely conserved role in epigenetic memory.
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26
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Kako K, Kim JD, Fukamizu A. Emerging impacts of biological methylation on genetic information. J Biochem 2019; 165:9-18. [PMID: 30219914 DOI: 10.1093/jb/mvy075] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/13/2018] [Indexed: 12/13/2022] Open
Abstract
The central dogma of molecular biology explains the fundamental flow of genetic information for life. Although genome sequence (DNA) itself is a static chemical signature, it includes multiple layers of information composed of mRNA, tRNA, rRNA and small RNAs, all of which are involved in protein synthesis and is passing from parents to offspring via DNA. Methylation is a biologically important modification, because DNA, RNAs and proteins, components of the central dogma, are methylated by a set of methyltransferases. Recent works focused on understanding a variety of biological methylation have shed light on new regulation of cellular functions. In this review, we briefly discuss some of those recent findings of methylation, including DNA, RNAs and proteins.
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Affiliation(s)
- Koichiro Kako
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan.,Faculty of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Jun-Dal Kim
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Akiyoshi Fukamizu
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan.,International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
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27
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Perez MF, Lehner B. Intergenerational and transgenerational epigenetic inheritance in animals. Nat Cell Biol 2019; 21:143-151. [PMID: 30602724 DOI: 10.1038/s41556-018-0242-9] [Citation(s) in RCA: 300] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/29/2018] [Indexed: 12/12/2022]
Abstract
Animals transmit not only DNA but also other molecules, such as RNA, proteins and metabolites, to their progeny via gametes. It is currently unclear to what extent these molecules convey information between generations and whether this information changes according to their physiological state and environment. Here, we review recent work on the molecular mechanisms by which 'epigenetic' information is transmitted between generations over different timescales, and the importance of this information for development and physiology.
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Affiliation(s)
- Marcos Francisco Perez
- Systems Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Ben Lehner
- Systems Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
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28
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Tabuchi TM, Rechtsteiner A, Jeffers TE, Egelhofer TA, Murphy CT, Strome S. Caenorhabditis elegans sperm carry a histone-based epigenetic memory of both spermatogenesis and oogenesis. Nat Commun 2018; 9:4310. [PMID: 30333496 PMCID: PMC6193031 DOI: 10.1038/s41467-018-06236-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 08/15/2018] [Indexed: 12/21/2022] Open
Abstract
Paternal contributions to epigenetic inheritance are not well understood. Paternal contributions via marked nucleosomes are particularly understudied, in part because sperm in some organisms replace the majority of nucleosome packaging with protamine packaging. Here we report that in Caenorhabditis elegans sperm, the genome is packaged in nucleosomes and carries a histone-based epigenetic memory of genes expressed during spermatogenesis, which unexpectedly include genes well known for their expression during oogenesis. In sperm, genes with spermatogenesis-restricted expression are uniquely marked with both active and repressive marks, which may reflect a sperm-specific chromatin signature. We further demonstrate that epigenetic information provided by sperm is important and in fact sufficient to guide proper germ cell development in offspring. This study establishes one mode of paternal epigenetic inheritance and offers a potential mechanism for how the life experiences of fathers may impact the development and health of their descendants. Paternal contributions to epigenetic inheritance via nucleosomes are poorly understood, as sperm in many organisms replace the majority of nucleosomes with protamines. Here the authors provide evidence that Caenorhabditis elegans sperm retain histone packaging of the genome and provide a histone-based epigenetic memory that is important for germ cell development in offspring.
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Affiliation(s)
- Tomoko M Tabuchi
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Andreas Rechtsteiner
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Tess E Jeffers
- Department of Molecular Biology and LSI Genomics, Carl Icahn Lab 148, Princeton University, Princeton, NJ, 08545, USA
| | - Thea A Egelhofer
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Coleen T Murphy
- Department of Molecular Biology and LSI Genomics, Carl Icahn Lab 148, Princeton University, Princeton, NJ, 08545, USA
| | - Susan Strome
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA.
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29
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Provataris P, Meusemann K, Niehuis O, Grath S, Misof B. Signatures of DNA Methylation across Insects Suggest Reduced DNA Methylation Levels in Holometabola. Genome Biol Evol 2018; 10:1185-1197. [PMID: 29697817 PMCID: PMC5915941 DOI: 10.1093/gbe/evy066] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2018] [Indexed: 12/20/2022] Open
Abstract
It has been experimentally shown that DNA methylation is involved in the regulation of gene expression and the silencing of transposable element activity in eukaryotes. The variable levels of DNA methylation among different insect species indicate an evolutionarily flexible role of DNA methylation in insects, which due to a lack of comparative data is not yet well-substantiated. Here, we use computational methods to trace signatures of DNA methylation across insects by analyzing transcriptomic and genomic sequence data from all currently recognized insect orders. We conclude that: 1) a functional methylation system relying exclusively on DNA methyltransferase 1 is widespread across insects. 2) DNA methylation has potentially been lost or extremely reduced in species belonging to springtails (Collembola), flies and relatives (Diptera), and twisted-winged parasites (Strepsiptera). 3) Holometabolous insects display signs of reduced DNA methylation levels in protein-coding sequences compared with hemimetabolous insects. 4) Evolutionarily conserved insect genes associated with housekeeping functions tend to display signs of heavier DNA methylation in comparison to the genomic/transcriptomic background. With this comparative study, we provide the much needed basis for experimental and detailed comparative analyses required to gain a deeper understanding on the evolution and function of DNA methylation in insects.
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Affiliation(s)
- Panagiotis Provataris
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
| | - Karen Meusemann
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
- Evolutionary Biology and Ecology, Institute of Biology I (Zoology), Albert Ludwig University Freiburg, Freiburg (Brsg.), Germany
- Australian National Insect Collection, CSIRO National Research Collections Australia, Acton, Australian Capital Territory, Australia
| | - Oliver Niehuis
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
- Evolutionary Biology and Ecology, Institute of Biology I (Zoology), Albert Ludwig University Freiburg, Freiburg (Brsg.), Germany
| | - Sonja Grath
- Division of Evolutionary Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg, Germany
- Corresponding authors: E-mails: ;
| | - Bernhard Misof
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
- Corresponding authors: E-mails: ;
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30
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Weinhouse C, Truong L, Meyer JN, Allard P. Caenorhabditis elegans as an emerging model system in environmental epigenetics. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2018; 59:560-575. [PMID: 30091255 PMCID: PMC6113102 DOI: 10.1002/em.22203] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 04/13/2018] [Accepted: 04/19/2018] [Indexed: 05/19/2023]
Abstract
The roundworm Caenorhabitis elegans has been an established model organism for the study of genetics and developmental biology, including studies of transcriptional regulation, since the 1970s. This model organism has continued to be used as a classical model system as the field of transcriptional regulation has expanded to include scientific advances in epigenetics and chromatin biology. In the last several decades, C. elegans has emerged as a powerful model for environmental toxicology, particularly for the study of chemical genotoxicity. Here, we outline the utility and applicability of C. elegans as a powerful model organism for mechanistic studies of environmental influences on the epigenome. Our goal in this article is to inform the field of environmental epigenetics of the strengths and limitations of the well-established C. elegans model organism as an emerging model for medium-throughput, in vivo exploration of the role of exogenous chemical stimuli in transcriptional regulation, developmental epigenetic reprogramming, and epigenetic memory and inheritance. As the field of environmental epigenetics matures, and research begins to map mechanisms underlying observed associations, new toolkits and model systems, particularly manipulable, scalable in vivo systems that accurately model human transcriptional regulatory circuits, will provide an essential experimental bridge between in vitro biochemical experiments and mammalian model systems. Environ. Mol. Mutagen. 59:560-575, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Caren Weinhouse
- Duke Global Health Institute, Duke University, Durham, North Carolina
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Lisa Truong
- UCLA Human Genetics and Genomic Analysis Training Program, University of California, Los Angeles; Los Angeles, California
| | - Joel N. Meyer
- Duke Global Health Institute, Duke University, Durham, North Carolina
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Patrick Allard
- Institute for Society and Genetics, University of California at Los Angeles, Los Angeles, California
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31
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Nanan KK, Ocheltree C, Sturgill D, Mandler MD, Prigge M, Varma G, Oberdoerffer S. Independence between pre-mRNA splicing and DNA methylation in an isogenic minigene resource. Nucleic Acids Res 2017; 45:12780-12797. [PMID: 29244186 PMCID: PMC5727405 DOI: 10.1093/nar/gkx900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 09/13/2017] [Accepted: 09/25/2017] [Indexed: 12/27/2022] Open
Abstract
Actively transcribed genes adopt a unique chromatin environment with characteristic patterns of enrichment. Within gene bodies, H3K36me3 and cytosine DNA methylation are elevated at exons of spliced genes and have been implicated in the regulation of pre-mRNA splicing. H3K36me3 is further responsive to splicing, wherein splicing inhibition led to a redistribution and general reduction over gene bodies. In contrast, little is known of the mechanisms supporting elevated DNA methylation at actively spliced genic locations. Recent evidence associating the de novo DNA methyltransferase Dnmt3b with H3K36me3-rich chromatin raises the possibility that genic DNA methylation is influenced by splicing-associated H3K36me3. Here, we report the generation of an isogenic resource to test the direct impact of splicing on chromatin. A panel of minigenes of varying splicing potential were integrated into a single FRT site for inducible expression. Profiling of H3K36me3 confirmed the established relationship to splicing, wherein levels were directly correlated with splicing efficiency. In contrast, DNA methylation was equivalently detected across the minigene panel, irrespective of splicing and H3K36me3 status. In addition to revealing a degree of independence between genic H3K36me3 and DNA methylation, these findings highlight the generated minigene panel as a flexible platform for the query of splicing-dependent chromatin modifications.
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Affiliation(s)
- Kyster K. Nanan
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cody Ocheltree
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David Sturgill
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mariana D. Mandler
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maria Prigge
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Garima Varma
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shalini Oberdoerffer
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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32
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Hu J, Barrett RDH. Epigenetics in natural animal populations. J Evol Biol 2017; 30:1612-1632. [PMID: 28597938 DOI: 10.1111/jeb.13130] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 06/01/2017] [Accepted: 06/03/2017] [Indexed: 12/22/2022]
Abstract
Phenotypic plasticity is an important mechanism for populations to buffer themselves from environmental change. While it has long been appreciated that natural populations possess genetic variation in the extent of plasticity, a surge of recent evidence suggests that epigenetic variation could also play an important role in shaping phenotypic responses. Compared with genetic variation, epigenetic variation is more likely to have higher spontaneous rates of mutation and a more sensitive reaction to environmental inputs. In our review, we first provide an overview of recent studies on epigenetically encoded thermal plasticity in animals to illustrate environmentally-mediated epigenetic effects within and across generations. Second, we discuss the role of epigenetic effects during adaptation by exploring population epigenetics in natural animal populations. Finally, we evaluate the evolutionary potential of epigenetic variation depending on its autonomy from genetic variation and its transgenerational stability. Although many of the causal links between epigenetic variation and phenotypic plasticity remain elusive, new data has explored the role of epigenetic variation in facilitating evolution in natural populations. This recent progress in ecological epigenetics will be helpful for generating predictive models of the capacity of organisms to adapt to changing climates.
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Affiliation(s)
- J Hu
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
| | - R D H Barrett
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
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Chang AYF, Liao BY. Recruitment of histone modifications to assist mRNA dosage maintenance after degeneration of cytosine DNA methylation during animal evolution. Genome Res 2017; 27:1513-1524. [PMID: 28720579 PMCID: PMC5580711 DOI: 10.1101/gr.221739.117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/05/2017] [Indexed: 12/24/2022]
Abstract
Following gene duplication, mRNA expression of the duplicated gene is reduced to maintain mRNA dosage. In mammals, this process is achieved with increased cytosine DNA methylation of the promoters of duplicated genes to suppress transcriptional initiation. However, not all animal species possess a full apparatus for cytosine DNA methylation. For such species, such as the roundworm (Caenorhabditis elegans, "worm" hereafter) or fruit fly (Drosophila melanogaster, "fly" hereafter), it is unclear how reduced expression of duplicated genes has been achieved evolutionarily. Here, we hypothesize that in the absence of a classical cytosine DNA methylation pathway, histone modifications play an increasing role in maintaining mRNA dosage following gene duplication. We initially verified that reduced gene expression of duplicated genes had occurred in the worm, fly, and mouse (Mus musculus). Next, several histone marks, with the capacity to control mRNA abundance in the models studied, were examined. In the worm and fly, but not in the mouse, multiple histone modifications were found to assist mRNA dosage maintenance following gene duplication events and the possible involvement of adenine DNA methylation in this process was excluded. Furthermore, the histone marks and acting regions that mediated the reduction in duplicated gene expression were found to be largely organism specific. Thus, it appears that many of the histone marks that maintain mRNA dosage were independently recruited during the evolution of worms and flies to compensate for the loss of cytosine DNA methylation machinery from their genomes.
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Affiliation(s)
- Andrew Ying-Fei Chang
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County 350, Taiwan, Republic of China
| | - Ben-Yang Liao
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County 350, Taiwan, Republic of China
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34
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Cell and Tissue Biology Paves a Path to Breast Cancer Prevention. Trends Cancer 2017; 3:313-315. [PMID: 28718407 DOI: 10.1016/j.trecan.2017.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 03/06/2017] [Indexed: 12/25/2022]
Abstract
We hypothesize that breast cancer susceptibility stems from interactions between difficult-to-modify cultural and dietary habits and aging processes that are modifiable. We propose a pathway to prevention that uses human organotypic systems that recapitulate hallmarks of aging in order to better understand and to modulate the biological consequences of aging in breast.
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35
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Gong Z, Yin H, Ma X, Liu B, Han Z, Gou L, Cai J. Widespread 5-methylcytosine in the genomes of avian Coccidia and other apicomplexan parasites detected by an ELISA-based method. Parasitol Res 2017; 116:1573-1579. [PMID: 28361273 DOI: 10.1007/s00436-017-5434-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 03/21/2017] [Indexed: 02/07/2023]
Abstract
To date, little is known about cytosine methylation in the genomic DNA of apicomplexan parasites, although it has been confirmed that this important epigenetic modification exists in many lower eukaryotes, plants, and animals. In the present study, ELISA-based detection demonstrated that low levels of 5-methylcytosine (5-mC) are present in Eimeria spp., Toxoplasma gondii, Cryptosporidium spp., and Neospora caninum. The proportions of 5-mC in genomic DNA were 0.18 ± 0.02% in E tenella sporulated oocysts, 0.19 ± 0.01% in E. tenella second-generation merozoites, 0.22 ± 0.04% in T. gondii tachyzoites, 0.28 ± 0.03% in N. caninum tachyzoites, and 0.06 ± 0.01, 0.11 ± 0.01, and 0.09 ± 0.01% in C. andersoni, C. baileyi, and C. parvum sporulated oocysts, respectively. In addition, we found that the percentages of 5-mC in E. tenella varied considerably at different life stages, with sporozoites having the highest percentage of 5-mC (0.78 ± 0.10%). Similar stage differences in 5-mC were also found in E. maxima, E. necatrix, and E. acervulina, the levels of 5-mC in their sporozoites being 4.3-, 1.8-, 2.5-, and 2.0-fold higher than that of sporulated oocysts, respectively (p < 0.01). Furthermore, a total DNA methyltransferase-like activity was detected in whole cell extracts prepared from E. tenella sporozoites. In conclusion, genomic DNA methylation is present in these apicomplexan parasites and may play a role in the stage conversion of Eimeria.
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Affiliation(s)
- Zhenxing Gong
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Hao Yin
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Xueting Ma
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Baohong Liu
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Zhenglan Han
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Lingqiao Gou
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Jianping Cai
- State Key Laboratory of Veterinary Etiological Biology; Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Lanzhou, Gansu Province, 730046, People's Republic of China. .,Jiangsu Co-Innovation Center for Prevention and Control of Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 225009, People's Republic of China.
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Rondon R, Grunau C, Fallet M, Charlemagne N, Sussarellu R, Chaparro C, Montagnani C, Mitta G, Bachère E, Akcha F, Cosseau C. Effects of a parental exposure to diuron on Pacific oyster spat methylome. ENVIRONMENTAL EPIGENETICS 2017; 3:dvx004. [PMID: 29492306 PMCID: PMC5804544 DOI: 10.1093/eep/dvx004] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/14/2017] [Accepted: 03/07/2017] [Indexed: 05/18/2023]
Abstract
Environmental epigenetic is an emerging field that studies the cause-effect relationship between environmental factors and heritable trait via an alteration in epigenetic marks. This field has received much attentions since the impact of environmental factors on different epigenetic marks have been shown to be associated with a broad range of phenotypic disorders in natural ecosystems. Chemical pollutants have been shown to affect immediate epigenetic information carriers of several aquatic species but the heritability of the chromatin marks and the consequences for long term adaptation remain open questions. In this work, we investigated the impact of the diuron herbicide on the DNA methylation pattern of spat from exposed Crassotrea gigas genitors. This oyster is one of the most important mollusk species produced worldwide and a key coastal economic resource in France. The whole genome bisulfite sequencing (WGBS, BS-Seq) was applied to obtain a methylome at single nucleotide resolution on DNA extracted from spat issued from diuron exposed genitors comparatively to control spat. We showed that the parental diuron exposure has an impact on the DNA methylation pattern of its progeny. Most of the differentially methylated regions occurred within coding sequences and we showed that this change in methylation level correlates with RNA level only in a very small group of genes. Although the DNA methylation profile is variable between individuals, we showed conserved DNA methylation patterns in response to parental diuron exposure. This relevant result opens perspectives for the setting of new markers based on epimutations as early indicators of marine pollutions.
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Affiliation(s)
- Rodolfo Rondon
- Ifremer, IHPE UMR 5244, Univ. Perpignan Via Domitia, CNRS, Univ. Montpellier, F-34095 Montpellier, France
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Christoph Grunau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Manon Fallet
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Nicolas Charlemagne
- Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l’ile d’Yeu, BP 21105, 44311 Nantes Cedex 03, France
| | - Rossana Sussarellu
- Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l’ile d’Yeu, BP 21105, 44311 Nantes Cedex 03, France
| | - Cristian Chaparro
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Caroline Montagnani
- Ifremer, IHPE UMR 5244, Univ. Perpignan Via Domitia, CNRS, Univ. Montpellier, F-34095 Montpellier, France
| | - Guillaume Mitta
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Evelyne Bachère
- Ifremer, IHPE UMR 5244, Univ. Perpignan Via Domitia, CNRS, Univ. Montpellier, F-34095 Montpellier, France
| | - Farida Akcha
- Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l’ile d’Yeu, BP 21105, 44311 Nantes Cedex 03, France
| | - Céline Cosseau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, CNRS, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
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37
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Koch A, Kang HG, Steinbrenner J, Dempsey DA, Klessig DF, Kogel KH. MORC Proteins: Novel Players in Plant and Animal Health. FRONTIERS IN PLANT SCIENCE 2017; 8:1720. [PMID: 29093720 PMCID: PMC5651269 DOI: 10.3389/fpls.2017.01720] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/20/2017] [Indexed: 05/02/2023]
Abstract
Microrchidia (MORC) proteins comprise a family of proteins that have been identified in prokaryotes and eukaryotes. They are defined by two hallmark domains: a GHKL-type ATPase and an S5 fold. MORC proteins in plants were first discovered via a genetic screen for Arabidopsis mutants compromised for resistance to a viral pathogen. Subsequent studies expanded their role in plant immunity and revealed their involvement in gene silencing and transposable element repression. Emerging data suggest that MORC proteins also participate in pathogen-induced chromatin remodeling and epigenetic gene regulation. In addition, biochemical analyses recently demonstrated that plant MORCs have topoisomerase II (topo II)-like DNA modifying activities that may be important for their function. Interestingly, animal MORC proteins exhibit many parallels with their plant counterparts, as they have been implicated in disease development and gene silencing. In addition, human MORCs, like plant MORCs, bind salicylic acid and this inhibits some of their topo II-like activities. In this review, we will focus primarily on plant MORCs, although relevant comparisons with animal MORCs will be provided.
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Affiliation(s)
- Aline Koch
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
| | - Hong-Gu Kang
- Department of Biology, Texas State University, San Marcos, TX, United States
| | - Jens Steinbrenner
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
| | | | - Daniel F. Klessig
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
- *Correspondence: Daniel F. Klessig
| | - Karl-Heinz Kogel
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
- Karl-Heinz Kogel
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38
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39
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Kulkarni A, Lightfoot JW, Streit A. Germline organization in Strongyloides nematodes reveals alternative differentiation and regulation mechanisms. Chromosoma 2016; 125:725-45. [PMID: 26661737 PMCID: PMC5023735 DOI: 10.1007/s00412-015-0562-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 11/15/2015] [Accepted: 11/16/2015] [Indexed: 11/14/2022]
Abstract
Nematodes of the genus Strongyloides are important parasites of vertebrates including man. Currently, little is known about their germline organization or reproductive biology and how this influences their parasitic life strategies. Here, we analyze the structure of the germline in several Strongyloides and closely related species and uncover striking differences in the development, germline organization, and fluid dynamics compared to the model organism Caenorhabditis elegans. With a focus on Strongyloides ratti, we reveal that the proliferation of germ cells is restricted to early and mid-larval development, thus limiting the number of progeny. In order to understand key germline events (specifically germ cell progression and the transcriptional status of the germline), we monitored conserved histone modifications, in particular H3Pser10 and H3K4me3. The evolutionary significance of these events is subsequently highlighted through comparisons with six other nematode species, revealing underlying complexities and variations in the development of the germline among nematodes.
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Affiliation(s)
- Arpita Kulkarni
- Department Evolutionary Biology, Max Planck Institute for Developmental Biology, D-72076, Tübingen, Germany
| | - James W Lightfoot
- Department Evolutionary Biology, Max Planck Institute for Developmental Biology, D-72076, Tübingen, Germany
| | - Adrian Streit
- Department Evolutionary Biology, Max Planck Institute for Developmental Biology, D-72076, Tübingen, Germany.
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Timoshevskiy VA, Herdy JR, Keinath MC, Smith JJ. Cellular and Molecular Features of Developmentally Programmed Genome Rearrangement in a Vertebrate (Sea Lamprey: Petromyzon marinus). PLoS Genet 2016; 12:e1006103. [PMID: 27341395 PMCID: PMC4920378 DOI: 10.1371/journal.pgen.1006103] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 05/13/2016] [Indexed: 11/21/2022] Open
Abstract
The sea lamprey (Petromyzon marinus) represents one of the few vertebrate species known to undergo large-scale programmatic elimination of genomic DNA over the course of its normal development. Programmed genome rearrangements (PGRs) result in the reproducible loss of ~20% of the genome from somatic cell lineages during early embryogenesis. Studies of PGR hold the potential to provide novel insights related to the maintenance of genome stability during the cell cycle and coordination between mechanisms responsible for the accurate distribution of chromosomes into daughter cells, yet little is known regarding the mechanistic basis or cellular context of PGR in this or any other vertebrate lineage. Here we identify epigenetic silencing events that are associated with the programmed elimination of DNA and describe the spatiotemporal dynamics of PGR during lamprey embryogenesis. In situ analyses reveal that the earliest DNA methylation (and to some extent H3K9 trimethylation) events are limited to specific extranuclear structures (micronuclei) containing eliminated DNA. During early embryogenesis a majority of micronuclei (~60%) show strong enrichment for repressive chromatin modifications (H3K9me3 and 5meC). These analyses also led to the discovery that eliminated DNA is packaged into chromatin that does not migrate with somatically retained chromosomes during anaphase, a condition that is superficially similar to lagging chromosomes observed in some cancer subtypes. Closer examination of “lagging” chromatin revealed distributions of repetitive elements, cytoskeletal contacts and chromatin contacts that provide new insights into the cellular mechanisms underlying the programmed loss of these segments. Our analyses provide additional perspective on the cellular and molecular context of PGR, identify new structures associated with elimination of DNA and reveal that PGR is completed over the course of several successive cell divisions. Lampreys possess a fascinating genome biology wherein large portions of the genome, including large numbers of genes, are programmatically deleted during development. The lamprey therefore represents a uniquely informative system with respect to several broad areas of biology, including genome stability/rearrangement, epigenetic silencing, and the establishment and maintenance of pluripotency. However, little is known regarding the cellular context or mechanism of deletion, partly due to the challenges of observing rearrangements in situ. Here we present analyses and new techniques that significantly advance our understanding of the subcellular context of programmed rearrangements and interactions between programmed deletion and canonical DNA silencing mechanisms. These analyses demonstrate that DNA elimination occurs earlier in embryogenesis than was previously recognized and reveal several new cellular and molecular aspects of programmed DNA loss. Specifically we show that eliminated DNA exhibits a unique migration pattern during cell division, is packaged into discreet subcellular structures later in the cell cycle, and undergoes epigenetic silencing through DNA and histone methylation. These observations provide new insight into the mechanisms underlying programmed DNA loss and suggest a functional link between programmed DNA loss and other, more conserved gene silencing pathways.
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Affiliation(s)
| | - Joseph R. Herdy
- Department of Biology, University of Kentucky, Lexington, Kentucky, United States of America
- Laboratory of Genetics, The Salk Institute, La Jolla, California, United States of America
| | - Melissa C. Keinath
- Department of Biology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Jeramiah J. Smith
- Department of Biology, University of Kentucky, Lexington, Kentucky, United States of America
- * E-mail:
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41
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Haemonchus contortus: Genome Structure, Organization and Comparative Genomics. ADVANCES IN PARASITOLOGY 2016; 93:569-98. [PMID: 27238013 DOI: 10.1016/bs.apar.2016.02.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
One of the first genome sequencing projects for a parasitic nematode was that for Haemonchus contortus. The open access data from the Wellcome Trust Sanger Institute provided a valuable early resource for the research community, particularly for the identification of specific genes and genetic markers. Later, a second sequencing project was initiated by the University of Melbourne, and the two draft genome sequences for H. contortus were published back-to-back in 2013. There is a pressing need for long-range genomic information for genetic mapping, population genetics and functional genomic studies, so we are continuing to improve the Wellcome Trust Sanger Institute assembly to provide a finished reference genome for H. contortus. This review describes this process, compares the H. contortus genome assemblies with draft genomes from other members of the strongylid group and discusses future directions for parasite genomics using the H. contortus model.
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42
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Kesäniemi JE, Heikkinen L, Knott KE. DNA Methylation and Potential for Epigenetic Regulation in Pygospio elegans. PLoS One 2016; 11:e0151863. [PMID: 27008314 PMCID: PMC4805255 DOI: 10.1371/journal.pone.0151863] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/04/2016] [Indexed: 01/24/2023] Open
Abstract
Transitions in developmental mode are common evolutionarily, but how and why they occur is not understood. Developmental mode describes larval phenotypes, including morphology, ecology and behavior of larvae, which typically are generalized across different species. The polychaete worm Pygospio elegans is one of few species polymorphic in developmental mode, with multiple larval phenotypes, providing a possibility to examine the potential mechanisms allowing transitions in developmental mode. We investigated the presence of DNA methylation in P. elegans, and, since maternal provisioning is a key factor determining eventual larval phenotype, we compared patterns of DNA methylation in females during oogenesis in this species. We demonstrate that intragenic CpG site DNA methylation and many relevant genes necessary for DNA methylation occur in P. elegans. Methylation-sensitive AFLP analysis showed that gravid females with offspring differing in larval developmental mode have significantly different methylation profiles and that the females with benthic larvae and non-reproductive females from the same location also differ in their epigenetic profiles. Analysis of CpG sites in transcriptome data supported our findings of DNA methylation in this species and showed that CpG observed/expected ratios differ among females gravid with embryos destined to different developmental modes. The differences in CpG site DNA methylation patterns seen among the samples suggest a potential for epigenetic regulation of gene expression (through DNA methylation) in this species.
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Affiliation(s)
- Jenni E. Kesäniemi
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- * E-mail:
| | - Liisa Heikkinen
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - K. Emily Knott
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
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43
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Klosin A, Lehner B. Mechanisms, timescales and principles of trans-generational epigenetic inheritance in animals. Curr Opin Genet Dev 2016; 36:41-9. [DOI: 10.1016/j.gde.2016.04.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 12/20/2022]
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44
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Epigenetic mechanisms of dietary restriction induced aging in Drosophila. Exp Gerontol 2015; 72:38-44. [DOI: 10.1016/j.exger.2015.08.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 08/04/2015] [Accepted: 08/25/2015] [Indexed: 01/07/2023]
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45
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Metabolome and proteome changes with aging in Caenorhabditis elegans. Exp Gerontol 2015; 72:67-84. [PMID: 26390854 DOI: 10.1016/j.exger.2015.09.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 09/15/2015] [Accepted: 09/16/2015] [Indexed: 01/13/2023]
Abstract
To expand the understanding of aging in the model organism Caenorhabditis elegans, global quantification of metabolite and protein levels in young and aged nematodes was performed using mass spectrometry. With age, there was a decreased abundance of proteins functioning in transcription termination, mRNA degradation, mRNA stability, protein synthesis, and proteasomal function. Furthermore, there was altered S-adenosyl methionine metabolism as well as a decreased abundance of the S-adenosyl methionine synthetase (SAMS-1) protein. Other aging-related changes included alterations in free fatty acid levels and composition, decreased levels of ribosomal proteins, decreased levels of NADP-dependent isocitrate dehydrogenase (IDH1), a shift in the cellular redox state, an increase in sorbitol content, alterations in free amino acid levels, and indications of altered muscle function and sarcoplasmic reticulum Ca(2+) homeostasis. There were also decreases in pyrimidine and purine metabolite levels, most markedly nitrogenous bases. Supplementing the culture medium with cytidine (a pyrimidine nucleoside) or hypoxanthine (a purine base) increased lifespan slightly, suggesting that aging-induced alterations in ribonucleotide metabolism affect lifespan. An age-related increase in body size, lipotoxicity from ectopic yolk lipoprotein accumulation, a decline in NAD(+) levels, and mitochondrial electron transport chain dysfunction may explain many of these changes. In addition, dietary restriction in aged worms resulting from sarcopenia of the pharyngeal pump likely decreases the abundance of SAMS-1, possibly leading to decreased phosphatidylcholine levels, larger lipid droplets, and ER and mitochondrial stress. The complementary use of proteomics and metabolomics yielded unique insights into the molecular processes altered with age in C. elegans.
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46
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Epigenetic regulation of ageing: linking environmental inputs to genomic stability. Nat Rev Mol Cell Biol 2015; 16:593-610. [PMID: 26373265 DOI: 10.1038/nrm4048] [Citation(s) in RCA: 396] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ageing is affected by both genetic and non-genetic factors. Here, we review the chromatin-based epigenetic changes that occur during ageing, the role of chromatin modifiers in modulating lifespan and the importance of epigenetic signatures as biomarkers of ageing. We also discuss how epigenome remodelling by environmental stimuli affects several aspects of transcription and genomic stability, with important consequences for longevity, and outline epigenetic differences between the 'mortal soma' and the 'immortal germ line'. Finally, we discuss the inheritance of characteristics of ageing and potential chromatin-based strategies to delay or reverse hallmarks of ageing or age-related diseases.
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47
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Ernst UR, Van Hiel MB, Depuydt G, Boerjan B, De Loof A, Schoofs L. Epigenetics and locust life phase transitions. ACTA ACUST UNITED AC 2015; 218:88-99. [PMID: 25568455 DOI: 10.1242/jeb.107078] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Insects are one of the most successful classes on Earth, reflected in an enormous species richness and diversity. Arguably, this success is partly due to the high degree to which polyphenism, where one genotype gives rise to more than one phenotype, is exploited by many of its species. In social insects, for instance, larval diet influences the development into distinct castes; and locust polyphenism has tricked researchers for years into believing that the drastically different solitarious and gregarious phases might be different species. Solitarious locusts behave much as common grasshoppers. However, they are notorious for forming vast, devastating swarms upon crowding. These gregarious animals are shorter lived, less fecund and transmit their phase characteristics to their offspring. The behavioural gregarisation occurs within hours, yet the full display of gregarious characters takes several generations, as does the reversal to the solitarious phase. Hormones, neuropeptides and neurotransmitters influence some of the phase traits; however, none of the suggested mechanisms can account for all the observed differences, notably imprinting effects on longevity and fecundity. This is why, more recently, epigenetics has caught the interest of the polyphenism field. Accumulating evidence points towards a role for epigenetic regulation in locust phase polyphenism. This is corroborated in the economically important locust species Locusta migratoria and Schistocerca gregaria. Here, we review the key elements involved in phase transition in locusts and possible epigenetic regulation. We discuss the relative role of DNA methylation, histone modification and small RNA molecules, and suggest future research directions.
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Affiliation(s)
- Ulrich R Ernst
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
| | - Matthias B Van Hiel
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
| | - Geert Depuydt
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
| | - Bart Boerjan
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
| | - Arnold De Loof
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
| | - Liliane Schoofs
- Functional Genomics and Proteomics Lab, KU Leuven, Naamsestraat 59, bus 2465, B-3000 Leuven, Belgium
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Sun Q, Huang S, Wang X, Zhu Y, Chen Z, Chen D. N6-methyladenine functions as a potential epigenetic mark in eukaryotes. Bioessays 2015; 37:1155-62. [PMID: 26293475 DOI: 10.1002/bies.201500076] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
N(6)-methyladenine (6mA) is one of the most abundant types of DNA methylation, and plays an important role in bacteria; however, its roles in higher eukaryotes, such as plants, insects, and mammals, have been considered less important. Recent studies highlight that 6mA does indeed occur, and that it plays an important role in eukaryotes, such as worm, fly, and green algae, and thus the regulation of 6mA has emerged as a novel epigenetic mechanism in higher eukaryotes. Despite this intriguing development, a number of important issues regarding its biological roles are yet to be addressed. In this review, we focus on the 5mC and 6mA modifications in terms of their production, distribution, and the erasure of 6mA in higher eukaryotes including mammals. We perform an analysis of the potential functions of 6mA, hence widening understanding of this new epigenetic mark in higher eukaryotes, and suggesting future studies in this field.
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Affiliation(s)
- Qinmiao Sun
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Shoujun Huang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Center for Developmental Biology, School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Xiaona Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yuanxiang Zhu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zhenping Chen
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Dahua Chen
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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Abstract
With ever-increasing elder population, the high incidence of age-related diseases such as neurodegenerative disorders has turned out to be a huge public concern. Especially the elders and their families dreadfully suffer from the learning, behavioral and cognitive impairments. The lack of effective therapies for such a horrible symptom makes a great demanding for biological mechanism study for cognitive aging. Epigenetics is an emerging field that broadens the dimensions of mammalian genome blueprint. It is, unlike genetics, not only inheritable but also reversible. Recent studies suggest that DNA methylation, one of major epigenetic mechanisms, plays a pivotal role in the pathogenesis of age-related neurodegenerations and cognitive defects. In this review, the evolving knowledge of age-related cognitive functions and the potential DNA methylation mechanism of cognitive aging are discussed. That indicates the impairment of DNA methylation may be a crucial but reversible mechanism of behavioral and cognitive related neurodegeneration. The methods to examine the dynamics of DNA methylation patterns at tissue and single cell level and at the representative scale as well as the whole genome single base resolution are also briefly discussed. Importantly, the challenges of DNA methylation mechanism of cognitive aging research are brought up, and the possible solutions to tackle these difficulties are put forward.
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Affiliation(s)
- Xiangru Xu
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
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50
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Feng L, Chen X. Epigenetic regulation of germ cells-remember or forget? Curr Opin Genet Dev 2015; 31:20-7. [PMID: 25930104 DOI: 10.1016/j.gde.2015.04.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/02/2015] [Indexed: 12/18/2022]
Abstract
Unlike somatic cells, germ cells retain the potential to reproduce an entire new organism upon fertilization. In order to accomplish the process of fertilization, germ cells undergo an extreme cellular differentiation process known as gametogenesis in order to produce morphologically and functionally distinct oocyte and sperm. In addition to changes in genetic content changes from diploid to haploid, epigenetic mechanisms that modify chromatin state without altering primary DNA sequences have profound influence on germ cell differentiation and moreover, the transgenerational effect. In this review, we will go over the most recent discoveries on epigenetic regulations in germline differentiation and transgenerational inheritance across different metazoan species.
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Affiliation(s)
- Lijuan Feng
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, United States
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, United States.
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