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Fernando GCP, Khansari AR, Tort L. Response to chronic crowding stress in shy and bold behavioral groups of male and female zebrafish. Am J Physiol Regul Integr Comp Physiol 2024; 327:R275-R290. [PMID: 38842516 DOI: 10.1152/ajpregu.00041.2024] [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: 02/16/2024] [Revised: 05/08/2024] [Accepted: 05/14/2024] [Indexed: 06/07/2024]
Abstract
In recent years, there has been a burgeoning interest in exploring the nuances of animal stress physiology, particularly in relation to parameters such as sex and behavioral phenotype-dependent variations, which is crucial for understanding phenotypic variation and its role in evolutionary selection. However, a significant dearth remains in how chronic stressors affect organismal stress physiology concerning the aforesaid parameters. This void is even wider pertaining to the response of peripheral tissues, such as the skin, the organ with the highest surface contact area with the environment. Hence, we behaviorally grouped the zebrafishes based on their boldness and the body condition, whole body cortisol response, along with examining the transcriptional response, global DNA methylome, and oxidative DNA damage in the skin upon chronic crowding. Upon baseline conditions, clear distinction between bold and shy phenotypes was found, particularly in males. The boldness index score distribution exhibited greater uniformity in males than in females. Regarding the body condition response to chronic crowding, shy males showed a significant relative decline compared with their bold counterparts, while this trend did not hold true for females. qPCR data revealed distinctive expression patterns in key genes that play critical roles in cellular processes such as stress-mediated gene regulation, immune response, oxidative stress protection, and maintenance of genomic integrity through epigenetic modifications across behavioral phenotypes and sexes under both with and without chronic crowding stress. Global DNA methylation levels significantly declined only in chronically crowded shy males, and sex/behavioral phenotype-dependent trends in oxidative DNA damage were identified.NEW & NOTEWORTHY This paper analyzes the response of zebrafish to crowding stress through a new approach focused on the peripheral response dynamics of the skin, the main mucosal tissue, and involving sex and behavioral phenotype influences. Shy males showed significant distress as observed by body condition, physiological and transcriptional response, and global DNA methylation. Nuances in stress response across behavioral phenotypes and sex indicate a genetic and behavioral specificity and further inherent epigenetic regulatory dimension.
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Affiliation(s)
- Gallage Chanuka P Fernando
- Department of Cell Biology Physiology and Immunology, Autonomous University of Barcelona, Bellaterra, Spain
| | - Ali R Khansari
- Department of Cell Biology Physiology and Immunology, Autonomous University of Barcelona, Bellaterra, Spain
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Lluis Tort
- Department of Cell Biology Physiology and Immunology, Autonomous University of Barcelona, Bellaterra, Spain
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2
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Kundu S, Ray A, Das Gupta S, Biswas A, Roy S, Kumar Tiwari N, Kumar VS, Das BK. Environmental bisphenol A disrupts methylation of steroidogenic genes in the ovary of Paradise threadfin Polynemus paradiseus via abnormal DNA methylation: Implications for human exposure and health risk assessment. CHEMOSPHERE 2024; 351:141236. [PMID: 38237780 DOI: 10.1016/j.chemosphere.2024.141236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/10/2024] [Accepted: 01/15/2024] [Indexed: 01/26/2024]
Abstract
Bisphenol A, endocrine-disrupting chemicals (EDCs) impacting disease development via epigenetic modifications, is crucial in transcriptional regulation. However, ecotoxicology's limited exploration of epigenetics prompted our study's objective: examining the extended exposure of riverine Bisphenol A (BPA), a potent EDC, on DNA methylation during female paradise threadfin (Polynemus paradiseus) reproductive maturation. Assessing BPA contamination in riverine water, we collected fish samples from two locations with distinct contamination levels. In the highly contaminated region (Hc), we observed elevated DNA methylation in aromatase (7.5-fold), 20β-HSD (3-fold), and FSHR (2-fold) genes. Hormone receptor investigation highlighted an escalating connection between transcriptional hyper-methylation and contamination levels. Additionally, our study revealed a positive correlation between oocyte growth and global DNA methylation, suggesting BPA's potential to modify DNA methylation in female paradise threadfins. This effect likely occurs through changes in hormone receptor expression, persisting throughout oocyte maturation. Notably, our research, the first of its kind in estuarine areas, confirmed BPA contamination in paradise threadfins, raising concerns about potential health risks for humans.
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Affiliation(s)
- Sourav Kundu
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Archisman Ray
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Subhadeep Das Gupta
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Ayan Biswas
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Shreya Roy
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Nitish Kumar Tiwari
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - V Santhana Kumar
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India
| | - Basanta Kumar Das
- ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700 120, West Bengal, India.
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3
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Jia X, Wyart C. Holographic Optogenetic Activation of Neurons Eliciting Locomotion in Head-Embedded Larval Zebrafish. Methods Mol Biol 2024; 2707:125-140. [PMID: 37668909 DOI: 10.1007/978-1-0716-3401-1_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Understanding how motor circuits are organized and recruited in order to perform complex behavior is an essential question of neuroscience. Here we present an optogenetic protocol on larval zebrafish that allows spatial selective control of neuronal activity within a genetically defined population. We combine holographic illumination with the use of effective opsin transgenic lines, alongside high-speed behavioral monitoring to dissect the motor circuits of the larval zebrafish.
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Affiliation(s)
- Xinyu Jia
- Sorbonne Université, Institut du Cerveau (ICM), Paris, France
| | - Claire Wyart
- Sorbonne Université, Institut du Cerveau (ICM), Paris, France.
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Rasal KD, Mohapatra S, Kumar PV, K SR, Asgolkar P, Acharya A, Dey D, Shinde S, Vasam M, Kumar R, Sundaray JK. DNA Methylation Profiling of Ovarian Tissue of Climbing Perch (Anabas testudienus) in Response to Monocrotophos Exposure. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2023; 25:1123-1135. [PMID: 37870741 DOI: 10.1007/s10126-023-10264-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/17/2023] [Indexed: 10/24/2023]
Abstract
Epigenetic modifications like DNA methylation can alter an organism's phenotype without changing its DNA sequence. Exposure to environmental toxicants has the potential to change the resilience of aquatic species. However, little information is available on the dynamics of DNA methylation in fish gonadal tissues in response to organophosphates. In the present work, reduced-representation bisulfite sequencing was performed to identify DNA methylation patterns in the ovarian tissues of Anabas testudienus exposed to organophosphates, specifically monocrotophos (MCP). Through sequencing, an average of 41,087 methylated cytosine sites were identified and distributed in different parts of genes, i.e., in transcription start sites (TSS), promoters, exons, etc. A total of 1058 and 1329 differentially methylated regions (DMRs) were detected as hyper-methylated and hypo-methylated in ovarian tissues, respectively. Utilizing whole-genome data of the climbing perch, the DMRs, and their associated overlapping genes revealed a total of 22 genes within exons, 45 genes at transcription start sites (TSS), and 218 genes in intergenic regions. Through gene ontology analysis, a total of 16 GO terms particularly involved in ovarian follicular development, response to oxidative stress, oocyte maturation, and multicellular organismal response to stress associated with reproductive biology were identified. After functional enrichment analysis, relevant DMGs such as steroid hormone biosynthesis (Cyp19a, 11-beta-HSD, 17-beta-HSD), hormone receptors (ar, esrrga), steroid metabolism (StAR), progesterone-mediated oocyte maturation (igf1ar, pgr), associated with ovarian development in climbing perch showed significant differential methylation patterns. The differentially methylated genes (DMGs) were subjected to analysis using real-time PCR, which demonstrated altered gene expression levels. This study revealed a molecular-level alteration in genes associated with ovarian development in response to chemical exposure. This work provides evidence for understanding the relationship between DNA methylation and gene regulation in response to chemicals that affect the reproductive fitness of aquatic animals.
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Affiliation(s)
- Kiran D Rasal
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, 751 002, Odisha, India
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Sujata Mohapatra
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, 751 002, Odisha, India
| | - Pokanti Vinay Kumar
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Shasti Risha K
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Prachi Asgolkar
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Arpit Acharya
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Diganta Dey
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Siba Shinde
- ICAR-Central Institute of Fisheries Education, Mumbai, 400 061, Maharashtra, India
| | - Manohar Vasam
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, 751 002, Odisha, India
| | - Rajesh Kumar
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, 751 002, Odisha, India
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Xu J, Zhang W, Zhong S, Xie X, Che H, Si W, Tuo X, Xu D, Zhao S. Microcystin-leucine-arginine affects brain gene expression programs and behaviors of offspring through paternal epigenetic information. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159032. [PMID: 36167133 DOI: 10.1016/j.scitotenv.2022.159032] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/01/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Microcystin-leucine-arginine (MC-LR) adversely affects male reproduction and interferes with the development of the offspring. Here, we establish a zebrafish (Danio rerio) model to understand the cross-generational effects of MC-LR in a male-lineage transmission pattern. F0 embryos were reared in water containing MC-LR (0, 5, and 25 μg/L) for 90 days and the developmental indices of F1 and F2 embryos were then measured with no MC-LR treatment. The results show that paternal MC-LR exposure reduced the hatching rate, heart rate and body weight in F1 and F2 generations. Global DNA methylation significantly increased in sperm and testes with the elevation expressions of DNA methyltransferases. Meanwhile, DNA methylation of brain-derived neurotrophic factor (bdnf) promoter was increased in sperm after paternal MC-LR exposure. Subsequently, increased DNA methylation of bdnf promoter and decreased gene expression of bdnf in the brain of F1 male zebrafish were detected. F1 offspring born to F0 males exhibit the depression of BDNF/AKT/CREB pathway and recapitulate these paternal neurodevelopment phenotypes in F2 offspring. In addition, the DNA methylations of dio3b and gad1b promoters were decreased and gene expressions of gad1b and dio3b were increased, accompanied with neurotransmitter disturbances in the brain of F1 male zebrafish after paternal MC-LR exposure. These data revealed that MC-LR displays a potential epigenetic impact on the germ line, reprogramming the epigenetic and transcriptional regulation of brain development, and contributing to aberrant expression of neurodevelopment-related genes and behavior disorders.
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Affiliation(s)
- Jiayi Xu
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Weiyun Zhang
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Shengzheng Zhong
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Xinxin Xie
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Huimin Che
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Weirong Si
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Xun Tuo
- College of Chemistry, Nanchang University, Nanchang 330031, China
| | - Dexiang Xu
- School of Public Health, Anhui Medical University, Hefei 230032, China
| | - Sujuan Zhao
- School of Public Health, Anhui Medical University, Hefei 230032, China.
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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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Sarkies P. Encyclopaedia of eukaryotic DNA methylation: from patterns to mechanisms and functions. Biochem Soc Trans 2022; 50:1179-1190. [PMID: 35521905 PMCID: PMC9246332 DOI: 10.1042/bst20210725] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 04/08/2022] [Accepted: 04/11/2022] [Indexed: 12/14/2022]
Abstract
DNA methylation is an epigenetic modification with a very long evolutionary history. However, DNA methylation evolves surprisingly rapidly across eukaryotes. The genome-wide distribution of methylation diversifies rapidly in different lineages, and DNA methylation is lost altogether surprisingly frequently. The growing availability of genomic and epigenomic sequencing across organisms highlights this diversity but also illuminates potential factors that could explain why both the DNA methylation machinery and its genome-wide distribution evolve so rapidly. Key to this are new discoveries about the fitness costs associated with DNA methylation, and new theories about how the fundamental biochemical mechanisms of DNA methylation introduction and maintenance could explain how new genome-wide patterns of methylation evolve.
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Affiliation(s)
- Peter Sarkies
- Department of Biochemistry, University of Oxford, Oxford, U.K
- MRC London Institute of Molecular Biology, London, U.K
- Institute of Clinical Sciences, Imperial College London, London, U.K
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8
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Blagov A, Zhigmitova EB, Sazonova MA, Mikhaleva LM, Kalmykov V, Shakhpazyan NK, Orekhova VA, Orekhov AN. Novel Models of Crohn's Disease Pathogenesis Associated with the Occurrence of Mitochondrial Dysfunction in Intestinal Cells. Int J Mol Sci 2022; 23:ijms23095141. [PMID: 35563530 PMCID: PMC9102004 DOI: 10.3390/ijms23095141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/28/2022] [Accepted: 05/02/2022] [Indexed: 12/10/2022] Open
Abstract
Crohn’s disease remains one of the challenging problems of modern medicine, and the development of new and effective and safer treatments against it is a dynamic field of research. To make such developments possible, it is important to understand the pathologic processes underlying the onset and progression of Crohn’s disease at the molecular and cellular levels. During the recent years, the involvement of mitochondrial dysfunction and associated chronic inflammation in these processes became evident. In this review, we discuss the published works on pathogenetic models of Crohn’s disease. These models make studying the role of mitochondrial dysfunction in the disease pathogenesis possible and advances the development of novel therapies.
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Affiliation(s)
- Alexander Blagov
- Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia; (A.B.); (M.A.S.); (V.K.)
| | - Elena B. Zhigmitova
- Federal State Budgetary Scientific Institution “Petrovsky National Research Centre of Surgery, A.P. Avtsyn Research Institute of Human Morphology”, 117418 Moscow, Russia; (E.B.Z.); (L.M.M.); (N.K.S.)
| | - Margarita A. Sazonova
- Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia; (A.B.); (M.A.S.); (V.K.)
| | - Liudmila M. Mikhaleva
- Federal State Budgetary Scientific Institution “Petrovsky National Research Centre of Surgery, A.P. Avtsyn Research Institute of Human Morphology”, 117418 Moscow, Russia; (E.B.Z.); (L.M.M.); (N.K.S.)
| | - Vladislav Kalmykov
- Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia; (A.B.); (M.A.S.); (V.K.)
| | - Nikolay K. Shakhpazyan
- Federal State Budgetary Scientific Institution “Petrovsky National Research Centre of Surgery, A.P. Avtsyn Research Institute of Human Morphology”, 117418 Moscow, Russia; (E.B.Z.); (L.M.M.); (N.K.S.)
| | - Varvara A. Orekhova
- Skolkovo Innovative Center, Institute for Atherosclerosis Research, 121609 Moscow, Russia
- Correspondence: (V.A.O.); (A.N.O.); Tel.: +7-9057506815 (A.N.O.)
| | - Alexander N. Orekhov
- Skolkovo Innovative Center, Institute for Atherosclerosis Research, 121609 Moscow, Russia
- Correspondence: (V.A.O.); (A.N.O.); Tel.: +7-9057506815 (A.N.O.)
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Gui L, Lu W, Shi M, Hu R, Yan zhou, Shen Y, Xu X, Liu J, Xia H, Wang Y, Li W, Lu Y. Liver DNA methylation and transcriptome between 1- and 3-year-old grass carp. AQUACULTURE AND FISHERIES 2022. [DOI: 10.1016/j.aaf.2020.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Terrazas-Salgado L, García-Gasca A, Betancourt-Lozano M, Llera-Herrera R, Alvarado-Cruz I, Yáñez-Rivera B. Epigenetic Transgenerational Modifications Induced by Xenobiotic Exposure in Zebrafish. Front Cell Dev Biol 2022; 10:832982. [PMID: 35281093 PMCID: PMC8914061 DOI: 10.3389/fcell.2022.832982] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/21/2022] [Indexed: 11/23/2022] Open
Abstract
Zebrafish (Danio rerio) is a well-established vertebrate model in ecotoxicology research that responds to a wide range of xenobiotics such as pesticides, drugs, and endocrine-disrupting compounds. The epigenome can interact with the environment and transform internal and/or external signals into phenotypic responses through changes in gene transcription. Environmental exposures can also generate epigenetic variations in offspring even by indirect exposure. In this review, we address the advantages of using zebrafish as an experimental animal model to study transgenerational epigenetic processes upon exposure to xenobiotics. We focused mostly on DNA methylation, although studies on post-translational modifications of histones, and non-coding RNAs related to xenobiotic exposure in zebrafish are also discussed. A revision of the methods used to study epigenetic changes in zebrafish revealed the relevance and reproducibility for epigenetics-related research. PubMed and Google Scholar databases were consulted for original research articles published from 2013 to date, by using six keywords: zebrafish, epigenetics, exposure, parental, transgenerational, and F2. From 499 articles identified, 92 were considered, of which 14 were selected as included F2 and epigenetic mechanisms. Current knowledge regarding the effect of xenobiotics on DNA methylation, histone modifications, and changes in non-coding RNAs expressed in F2 is summarized, along with key experimental design considerations to characterize transgenerational effects.
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Affiliation(s)
| | | | | | - Raúl Llera-Herrera
- Instituto de Ciencias del Mar y Limnología—Unidad Académica Mazatlán, Universidad Nacional Autónoma de México, Mazatlán, Mexico
| | - Isabel Alvarado-Cruz
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, Tucson, AZ, United States
| | - Beatriz Yáñez-Rivera
- Centro de Investigación en Alimentación y Desarrollo, A. C., Mazatlán, Mexico
- Consejo Nacional de Ciencia y Tecnología, México, Mexico
- *Correspondence: Beatriz Yáñez-Rivera,
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Gutierrez J, Platt R, Opazo JC, Ray DA, Hoffmann F, Vandewege M. Evolutionary history of the vertebrate Piwi gene family. PeerJ 2021; 9:e12451. [PMID: 34760405 PMCID: PMC8574217 DOI: 10.7717/peerj.12451] [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: 06/07/2021] [Accepted: 10/18/2021] [Indexed: 11/28/2022] Open
Abstract
PIWIs are regulatory proteins that belong to the Argonaute family. Piwis are primarily expressed in gonads and protect the germline against the mobilization and propagation of transposable elements (TEs) through transcriptional gene silencing. Vertebrate genomes encode up to four Piwi genes: Piwil1, Piwil2, Piwil3 and Piwil4, but their duplication history is unresolved. We leveraged phylogenetics, synteny and expression analyses to address this void. Our phylogenetic analysis suggests Piwil1 and Piwil2 were retained in all vertebrate members. Piwil4 was the result of Piwil1 duplication in the ancestor of gnathostomes, but was independently lost in ray-finned fishes and birds. Further, Piwil3 was derived from a tandem Piwil1 duplication in the common ancestor of marsupial and placental mammals, but was secondarily lost in Atlantogenata (Xenarthra and Afrotheria) and some rodents. The evolutionary rate of Piwil3 is considerably faster than any Piwi among all lineages, but an explanation is lacking. Our expression analyses suggest Piwi expression has mostly been constrained to gonads throughout vertebrate evolution. Vertebrate evolution is marked by two early rounds of whole genome duplication and many multigene families are linked to these events. However, our analyses suggest Piwi expansion was independent of whole genome duplications.
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Affiliation(s)
- Javier Gutierrez
- Department of Biology, Eastern New Mexico University, Portales, NM, United States of America
| | - Roy Platt
- Host Pathogen Interaction Program, Texas Biomedical Research Institute, San Antonio, TX, United States of America
| | - Juan C. Opazo
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
- Integrative Biology Group, Universidad Austral de Chile, Valdivia, Chile
| | - David A. Ray
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States of America
| | - Federico Hoffmann
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Starkville, MS, United States of America
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Starkville, MS, United States of America
| | - Michael Vandewege
- Department of Biology, Eastern New Mexico University, Portales, NM, United States of America
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Zhou M, Zhao Z, Zhao J, Wu M, Chen X. Gene expression profiling of DNA methyltransferase genes in Siniperca chuatsi based on transcriptome sequencing. JOURNAL OF FISH BIOLOGY 2021; 99:1755-1760. [PMID: 34310718 DOI: 10.1111/jfb.14862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/06/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
The mandarin fish (Siniperca chuatsi) DNA methyltransferase gene 1 (dnmt1) was highly expressed in the mesonephros, head kidney and gonad, whereas dnmt2 was expressed in most tissues. dnmt3a was highly expressed in the brain and spleen, but dnmt3b was mainly expressed in the brain and head kidney. The genes dnmt1 and dnmt2 were highly expressed in the early stages of embryonic development, and dnmt3a and dnmt3b were expressed later. These genes also showed certain changes after artificial diet acclimation, salinity adaptation and immune stress.
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Affiliation(s)
- Min Zhou
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China
| | - Ziwei Zhao
- Shanghai Collaborative Innovation for Aquatic Animal Genetics and Breeding, Shanghai Ocean University, Shanghai, China
| | - Jinliang Zhao
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China
| | - Minglin Wu
- Fisheries Research Institute, Anhui Academy of Agricultural Sciences, Hefei, China
| | - Xiaowu Chen
- Shanghai Collaborative Innovation for Aquatic Animal Genetics and Breeding, Shanghai Ocean University, Shanghai, China
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13
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Zupkovitz G, Kabiljo J, Kothmayer M, Schlick K, Schöfer C, Lagger S, Pusch O. Analysis of Methylation Dynamics Reveals a Tissue-Specific, Age-Dependent Decline in 5-Methylcytosine Within the Genome of the Vertebrate Aging Model Nothobranchius furzeri. Front Mol Biosci 2021; 8:627143. [PMID: 34222326 PMCID: PMC8242171 DOI: 10.3389/fmolb.2021.627143] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 06/02/2021] [Indexed: 12/12/2022] Open
Abstract
Erosion of the epigenetic DNA methylation landscape is a widely recognized hallmark of aging. Emerging advances in high throughput sequencing techniques, in particular DNA methylation data analysis, have resulted in the establishment of precise human and murine age prediction tools. In vertebrates, methylation of cytosine at the C5 position of CpG dinucleotides is executed by DNA methyltransferases (DNMTs) whereas the process of enzymatic demethylation is highly dependent on the activity of the ten-eleven translocation methylcytosine dioxygenase (TET) family of enzymes. Here, we report the identification of the key players constituting the DNA methylation machinery in the short-lived teleost aging model Nothobranchius furzeri. We present a comprehensive spatio-temporal expression profile of the methylation-associated enzymes from embryogenesis into late adulthood, thereby covering the complete killifish life cycle. Data mining of the N. furzeri genome produced five dnmt gene family orthologues corresponding to the mammalian DNMTs (DNMT1, 2, 3A, and 3B). Comparable to other teleost species, N. furzeri harbors multiple genomic copies of the de novo DNA methylation subfamily. A related search for the DNMT1 recruitment factor UHRF1 and TET family members resulted in the identification of N. furzeri uhrf1, tet1, tet2, and tet3. Phylogenetic analysis revealed high cross-species similarity on the amino acid level of all individual dnmts, tets, and uhrf1, emphasizing a high degree of functional conservation. During early killifish development all analyzed dnmts and tets showed a similar expression profile characterized by a strong increase in transcript levels after fertilization, peaking either at embryonic day 6 or at the black eye stage of embryonic development. In adult N. furzeri, DNA methylation regulating enzymes showed a ubiquitous tissue distribution. Specifically, we observed an age-dependent downregulation of dnmts, and to some extent uhrf1, which correlated with a significant decrease in global DNA methylation levels in the aging killifish liver and muscle. The age-dependent DNA methylation profile and spatio-temporal expression characteristics of its enzymatic machinery reported here may serve as an essential platform for the identification of an epigenetic aging clock in the new vertebrate model system N. furzeri.
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Affiliation(s)
- Gordin Zupkovitz
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria.,Department of Life Science Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria.,City of Vienna Competence Team Aging Tissue, Vienna, Austria
| | - Julijan Kabiljo
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria.,Department of General Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Vienna, Austria
| | - Michael Kothmayer
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Katharina Schlick
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Christian Schöfer
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Sabine Lagger
- Unit of Laboratory Animal Pathology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Oliver Pusch
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
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14
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González-Rodríguez P, Cheray M, Füllgrabe J, Salli M, Engskog-Vlachos P, Keane L, Cunha V, Lupa A, Li W, Ma Q, Dreij K, Rosenfeld MG, Joseph B. The DNA methyltransferase DNMT3A contributes to autophagy long-term memory. Autophagy 2021; 17:1259-1277. [PMID: 32876528 PMCID: PMC8143216 DOI: 10.1080/15548627.2020.1816664] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 10/25/2022] Open
Abstract
Macroautophagy/autophagy is a conserved catabolic pathway that targets cytoplasmic components for their degradation and recycling in an autophagosome-dependent lysosomal manner. Under physiological conditions, this process maintains cellular homeostasis. However, autophagy can be stimulated upon different forms of cellular stress, ranging from nutrient starvation to exposure to drugs. Thus, this pathway can be seen as a central component of the integrated and adaptive stress response. Here, we report that even brief induction of autophagy is coupled in vitro to a persistent downregulation of the expression of MAP1LC3 isoforms, which are key components of the autophagy core machinery. In fact, DNA-methylation mediated by de novo DNA methyltransferase DNMT3A of MAP1LC3 loci upon autophagy stimulation leads to the observed long-term decrease of MAP1LC3 isoforms at transcriptional level. Finally, we report that the downregulation of MAP1LC3 expression can be observed in vivo in zebrafish larvae and mice exposed to a transient autophagy stimulus. This epigenetic memory of autophagy provides some understanding of the long-term effect of autophagy induction and offers a possible mechanism for its decline upon aging, pathological conditions, or in response to treatment interventions.Abbreviations: ACTB: actin beta; ATG: autophagy-related; 5-Aza: 5-aza-2'-deoxycytidine; BafA1: bafilomycin A1; CBZ: carbamazepine; CDKN2A: cyclin dependent kinase inhibitor 2A; ChIP: chromatin immunoprecipitation; Clon.: clonidine; CpG: cytosine-guanine dinucleotide: DMSO: dimethyl sulfoxide; DNA: deoxyribonucleic acid; DNMT: DNA methyltransferase; DNMT1: DNA methyltransferase 1; DNMT3A: DNA methyltransferase alpha; DNMT3B: DNA methyltransferase beta; dpf: days post-fertilization; EBSS: Earle's balanced salt solution; EM: Zebrafish embryo medium; GABARAP: GABA type A receptor associated protein; GABARAPL1: GABA type A receptor associated protein like 1; GABARAPL2: GABA type A receptor associated protein like 2; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GRO-Seq: Global Run-On sequencing; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAP1LC3A: microtubule-associated protein 1 light chain 3 alpha; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MAP1LC3B2: microtubule-associated protein 1 light chain 3 beta 2; MEM: minimum essential medium; MEF: mouse embryonic fibroblasts; mRNA: messenger RNA; MTOR: mechanistic target of rapamycin kinase; PBS: phosphate-buffered saline; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; RB1CC1/FIP200: RB1 inducible coiled-coil 1; RT-qPCR: quantitative reverse transcription polymerase chain reaction; SQSTM1/p62: sequestosome 1; Starv.: starvation; Treh.: trehalose; ULK1: unc-51 like autophagy activating kinase 1.
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Affiliation(s)
- Patricia González-Rodríguez
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
| | - Mathilde Cheray
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
| | - Jens Füllgrabe
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Maria Salli
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
| | | | - Lily Keane
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Virginia Cunha
- Institute of Environmental Medicine, Biochemical Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Agata Lupa
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
| | - Wenbo Li
- Howard Hughes Medical Institute, Department of Medicine, School of Medicine, University of California, San Diego, California, USA
| | - Qi Ma
- Howard Hughes Medical Institute, Department of Medicine, School of Medicine, University of California, San Diego, California, USA
| | - Kristian Dreij
- Institute of Environmental Medicine, Biochemical Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Michael G. Rosenfeld
- Howard Hughes Medical Institute, Department of Medicine, School of Medicine, University of California, San Diego, California, USA
| | - Bertrand Joseph
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
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15
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Marchione AD, Thompson Z, Kathrein KL. DNA methylation and histone modifications are essential for regulation of stem cell formation and differentiation in zebrafish development. Brief Funct Genomics 2021:elab022. [PMID: 33782688 DOI: 10.1093/bfgp/elab022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 01/21/2023] Open
Abstract
The complex processes necessary for embryogenesis require a gene regulatory network that is complex and systematic. Gene expression regulates development and organogenesis, but this process is altered and fine-tuned by epigenetic regulators that facilitate changes in the chromatin landscape. Epigenetic regulation of embryogenesis adjusts the chromatin structure by modifying both DNA through methylation and nucleosomes through posttranslational modifications of histone tails. The zebrafish is a well-characterized model organism that is a quintessential tool for studying developmental biology. With external fertilization, low cost and high fecundity, the zebrafish are an efficient tool for studying early developmental stages. Genetic manipulation can be performed in vivo resulting in quick identification of gene function. Large-scale genome analyses including RNA sequencing, chromatin immunoprecipitation and chromatin structure all are feasible in the zebrafish. In this review, we highlight the key events in zebrafish development where epigenetic regulation plays a critical role from the early stem cell stages through differentiation and organogenesis.
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16
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Ross SE, Hesselson D, Bogdanovic O. Developmental Accumulation of Gene Body and Transposon Non-CpG Methylation in the Zebrafish Brain. Front Cell Dev Biol 2021; 9:643603. [PMID: 33748137 PMCID: PMC7978034 DOI: 10.3389/fcell.2021.643603] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/08/2021] [Indexed: 12/13/2022] Open
Abstract
DNA methylation predominantly occurs at CG dinucleotides in vertebrate genomes; however, non-CG methylation (mCH) is also detectable in vertebrate tissues, most notably in the nervous system. In mammals it is well established that mCH is targeted to CAC trinucleotides by DNMT3A during nervous system development where it is enriched in gene bodies and associated with transcriptional repression. Nevertheless, the conservation of developmental mCH accumulation and its deposition by DNMT3A is largely unexplored and has yet to be functionally demonstrated in other vertebrates. In this study, by analyzing DNA methylomes and transcriptomes of zebrafish brains, we identified enrichment of mCH at CAC trinucleotides (mCAC) at defined transposon motifs as well as in developmentally downregulated genes associated with developmental and neural functions. We further generated and analyzed DNA methylomes and transcriptomes of developing zebrafish larvae and demonstrated that, like in mammals, mCH accumulates during post-embryonic brain development. Finally, by employing CRISPR/Cas9 technology, we unraveled a conserved role for Dnmt3a enzymes in developmental mCAC deposition. Overall, this work demonstrates the evolutionary conservation of developmental mCH dynamics and highlights the potential of zebrafish as a model to study mCH regulation and function during normal and perturbed development.
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Affiliation(s)
- Samuel E Ross
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine, St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Daniel Hesselson
- Centenary Institute, The University of Sydney, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Ozren Bogdanovic
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, NSW, Australia.,School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
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17
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Sadeq S, Al-Hashimi S, Cusack CM, Werner A. Endogenous Double-Stranded RNA. Noncoding RNA 2021; 7:15. [PMID: 33669629 PMCID: PMC7930956 DOI: 10.3390/ncrna7010015] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 02/07/2023] Open
Abstract
The birth of long non-coding RNAs (lncRNAs) is closely associated with the presence and activation of repetitive elements in the genome. The transcription of endogenous retroviruses as well as long and short interspersed elements is not only essential for evolving lncRNAs but is also a significant source of double-stranded RNA (dsRNA). From an lncRNA-centric point of view, the latter is a minor source of bother in the context of the entire cell; however, dsRNA is an essential threat. A viral infection is associated with cytoplasmic dsRNA, and endogenous RNA hybrids only differ from viral dsRNA by the 5' cap structure. Hence, a multi-layered defense network is in place to protect cells from viral infections but tolerates endogenous dsRNA structures. A first line of defense is established with compartmentalization; whereas endogenous dsRNA is found predominantly confined to the nucleus and the mitochondria, exogenous dsRNA reaches the cytoplasm. Here, various sensor proteins recognize features of dsRNA including the 5' phosphate group of viral RNAs or hybrids with a particular length but not specific nucleotide sequences. The sensors trigger cellular stress pathways and innate immunity via interferon signaling but also induce apoptosis via caspase activation. Because of its central role in viral recognition and immune activation, dsRNA sensing is implicated in autoimmune diseases and used to treat cancer.
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Affiliation(s)
| | | | | | - Andreas Werner
- Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; (S.S.); (S.A.-H.); (C.M.C.)
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18
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Ross SE, Angeloni A, Geng FS, de Mendoza A, Bogdanovic O. Developmental remodelling of non-CG methylation at satellite DNA repeats. Nucleic Acids Res 2020; 48:12675-12688. [PMID: 33271598 PMCID: PMC7736785 DOI: 10.1093/nar/gkaa1135] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 11/03/2020] [Accepted: 11/06/2020] [Indexed: 12/15/2022] Open
Abstract
In vertebrates, DNA methylation predominantly occurs at CG dinucleotides however, widespread non-CG methylation (mCH) has been reported in mammalian embryonic stem cells and in the brain. In mammals, mCH is found at CAC trinucleotides in the nervous system, where it is associated with transcriptional repression, and at CAG trinucleotides in embryonic stem cells, where it positively correlates with transcription. Moreover, CAC methylation appears to be a conserved feature of adult vertebrate brains. Unlike any of those methylation signatures, here we describe a novel form of mCH that occurs in the TGCT context within zebrafish mosaic satellite repeats. TGCT methylation is inherited from both male and female gametes, remodelled during mid-blastula transition, and re-established during gastrulation in all embryonic layers. Moreover, we identify DNA methyltransferase 3ba (Dnmt3ba) as the primary enzyme responsible for the deposition of this mCH mark. Finally, we observe that TGCT-methylated repeats are specifically associated with H3K9me3-marked heterochromatin suggestive of a functional interplay between these two gene-regulatory marks. Altogether, this work provides insight into a novel form of vertebrate mCH and highlights the substrate diversity of vertebrate DNA methyltransferases.
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Affiliation(s)
- Samuel E Ross
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales 2010, Australia
| | - Allegra Angeloni
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales 2010, Australia
| | - Fan-Suo Geng
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales 2010, Australia
| | - Alex de Mendoza
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Ozren Bogdanovic
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, New South Wales 2010, Australia
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
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19
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Oliveira CCV, Fatsini E, Fernández I, Anjos C, Chauvigné F, Cerdà J, Mjelle R, Fernandes JMO, Cabrita E. Kisspeptin Influences the Reproductive Axis and Circulating Levels of microRNAs in Senegalese Sole. Int J Mol Sci 2020; 21:E9051. [PMID: 33260781 PMCID: PMC7730343 DOI: 10.3390/ijms21239051] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/11/2022] Open
Abstract
Kisspeptin regulates puberty and reproduction onset, acting upstream of the brain-pituitary-gonad (HPG) axis. This study aimed to test a kisspeptin-based hormonal therapy on cultured Senegalese sole (G1) breeders, known to have reproductive dysfunctions. A single intramuscular injection of KISS2-10 decapeptide (250 µg/kg) was tested in females and males during the reproductive season, and gonad maturation, sperm motility, plasma levels of gonadotropins (Fsh and Lh) and sex steroids (11-ketotestosterone, testosterone and estradiol), as well as changes in small non-coding RNAs (sncRNAs) in plasma, were investigated. Fsh, Lh, and testosterone levels increased after kisspeptin injection in both sexes, while sperm analysis did not show differences between groups. Let7e, miR-199a-3p and miR-100-5p were differentially expressed in females, while miR-1-3p miRNA was up-regulated in kisspeptin-treated males. In silico prediction of mRNAs targeted by miRNAs revealed that kisspeptin treatment might affect paracellular transporters, regulate structural and functional polarity of cells, neural networks and intracellular trafficking in Senegalese sole females; also, DNA methylation and sphingolipid metabolism might be altered in kisspeptin-treated males. Results demonstrated that kisspeptin stimulated gonadotropin and testosterone secretion in both sexes and induced an unanticipated alteration of plasma miRNAs, opening new research venues to understand how this neuropeptide impacts in fish HPG axis.
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Affiliation(s)
- Catarina C. V. Oliveira
- Center of Marine Sciences-CCMAR, University of Algarve, 8005-139 Faro, Portugal; (E.F.); (C.A.)
| | - Elvira Fatsini
- Center of Marine Sciences-CCMAR, University of Algarve, 8005-139 Faro, Portugal; (E.F.); (C.A.)
| | - Ignacio Fernández
- Aquaculture Research Center, Agrarian Technological Institute of Castile and Leon, Ctra. Arévalo, s/n, 40196 Segovia, Spain;
| | - Catarina Anjos
- Center of Marine Sciences-CCMAR, University of Algarve, 8005-139 Faro, Portugal; (E.F.); (C.A.)
| | - François Chauvigné
- IRTA-Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, 08193 Barcelona, Spain; (F.C.); (J.C.)
| | - Joan Cerdà
- IRTA-Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, 08193 Barcelona, Spain; (F.C.); (J.C.)
| | - Robin Mjelle
- Faculty of Bioscience and Aquaculture, Nord University, 8049 Bodø, Norway; (R.M.); (J.M.O.F.)
| | - Jorge M. O. Fernandes
- Faculty of Bioscience and Aquaculture, Nord University, 8049 Bodø, Norway; (R.M.); (J.M.O.F.)
| | - Elsa Cabrita
- Center of Marine Sciences-CCMAR, University of Algarve, 8005-139 Faro, Portugal; (E.F.); (C.A.)
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20
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Miller JGP, Jamwal A, Ilnytskyy Y, Hontela A, Wiseman SB. Dicamba elevates concentrations of S-adenosyl methionine but does not induce oxidative stress or alter DNA methylation in rainbow trout (Oncorhynchus mykiss) hepatocytes. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 36:100744. [PMID: 32950925 DOI: 10.1016/j.cbd.2020.100744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/04/2020] [Accepted: 09/07/2020] [Indexed: 02/05/2023]
Abstract
Dicamba is a benzoic acid herbicide used to target woody and broadleaf weeds in industrial, domestic, and municipal spheres. Because of its widespread use, dicamba is frequently detected in surface waters near sites of application. However, little is known regarding the effects of dicamba on freshwater fishes. In the present study, primary cultures of hepatocytes from rainbow trout (Oncorhynchus mykiss) were exposed to either an environmentally relevant (0.22 or 2.2 μg L-1) or supra-environmental (22 μg L-1) concentration of dicamba for 48 h to investigate if oxidative stress is a mechanism of toxicity. mRNA abundances of genes involved in the response to oxidative stress, levels of lipid peroxidation, and concentrations of glutathione and s-adenosyl methionine (SAM) were quantified. Results indicate that dicamba does not induce oxidative stress. However, exposure to 2.2 μg L-1 of dicamba did cause a 5.24-fold increase in concentrations of SAM. To investigate the mechanisms of increased SAM, effects of dicamba on global and genome-wide DNA methylation were quantified. Dicamba did not cause changes to DNA methylation. Overall, dicamba was not acutely toxic to hepatocytes and did not cause oxidative stress or changes in DNA methylation at environmentally relevant concentrations.
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Affiliation(s)
- Justin G P Miller
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Ankur Jamwal
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Yaroslav Ilnytskyy
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Alice Hontela
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada; Water Institute for Sustainable Environments (WISE), University of Lethbridge, Lethbridge, Alberta, Canada
| | - Steve B Wiseman
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada; Water Institute for Sustainable Environments (WISE), University of Lethbridge, Lethbridge, Alberta, Canada.
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21
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Lerebours A, Robson S, Sharpe C, Nagorskaya L, Gudkov D, Haynes-Lovatt C, Smith JT. Transcriptional Changes in the Ovaries of Perch from Chernobyl. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10078-10087. [PMID: 32686935 DOI: 10.1021/acs.est.0c02575] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fish have been highly exposed to radiation in freshwater systems after the Chernobyl Nuclear Power Plant (NPP) accident in 1986 and in freshwater and marine systems after the more recent Fukushima NPP accident in 2011. In the years after the accident, the radioactivity levels rapidly declined due to radioactive decay and environmental processes, but chronic lower dose exposures persisted. To gain insights into the long-term effects of environmental low dose radiation on fish ovaries development, a high-throughput transcriptomic approach including a de novo assembly was applied to different gonad phenotypes of female perch: developed gonads from reference lakes, developed/irradiated from medium contaminated lake, and both developed/irradiated and undeveloped from more highly contaminated lakes. This is the most comprehensive analysis to date of the gene responses in wildlife reproductive system to radiation. Some gene responses that were modulated in irradiated gonads were found to be involved in biological processes including cell differentiation and proliferation (ggnb2, mod5, rergl), cytoskeleton organization (k1C18, mtpn), gonad development (nell2, tcp4), lipid metabolism (ldah, at11b, nltp), reproduction (cyb5, cyp17A, ovos), DNA damage repair (wdhd1, rad51, hus1), and epigenetic mechanisms (dmap1). Identification of these genes provides a better understanding of the underlying molecular mechanisms underpinning the development of the gonad phenotypes of wild perch and how fish may respond to chronic exposure to radiation in their natural environment, though causal attribution of gene responses remains unclear in the undeveloped gonads.
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Affiliation(s)
- Adélaïde Lerebours
- School of the Environment, Geography and Geosciences, University of Portsmouth, Portsmouth PO1 3QL, United Kingdom
- School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Samuel Robson
- Centre for Enzyme Innovation, University of Portsmouth, Portsmouth PO1 2DT, United Kingdom
| | - Colin Sharpe
- School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Liubov Nagorskaya
- Applied Science Center for Bioresources of the National Academy of Sciences of Belarus, Minsk 220072, Belarus
| | - Dmitri Gudkov
- Institute of Hydrobiology of the National Academy of Sciences of Ukraine, Kiev UA-04210, Ukraine
| | | | - Jim T Smith
- School of the Environment, Geography and Geosciences, University of Portsmouth, Portsmouth PO1 3QL, United Kingdom
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22
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dnmt1 function is required to maintain retinal stem cells within the ciliary marginal zone of the zebrafish eye. Sci Rep 2020; 10:11293. [PMID: 32647199 PMCID: PMC7347529 DOI: 10.1038/s41598-020-68016-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 05/15/2020] [Indexed: 12/22/2022] Open
Abstract
The ciliary marginal zone (CMZ) of the zebrafish retina contains a population of actively proliferating resident stem cells, which generate retinal neurons throughout life. The maintenance methyltransferase, dnmt1, is expressed within the CMZ. Loss of dnmt1 function results in gene misregulation and cell death in a variety of developmental contexts, however, its role in retinal stem cell (RSC) maintenance is currently unknown. Here, we demonstrate that zebrafish dnmt1s872 mutants possess severe defects in RSC maintenance within the CMZ. Using a combination of immunohistochemistry, in situ hybridization, and a transgenic reporter assay, our results demonstrate a requirement for dnmt1 activity in the regulation of RSC proliferation, gene expression and in the repression of endogenous retroelements (REs). Ultimately, cell death is elevated in the dnmt1−/− CMZ, but in a p53-independent manner. Using a transgenic reporter for RE transposition activity, we demonstrate increased transposition in the dnmt1−/− CMZ. Taken together our data identify a critical role for dnmt1 function in RSC maintenance in the vertebrate eye.
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23
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Akdogan-Ozdilek B, Duval KL, Goll MG. Chromatin dynamics at the maternal to zygotic transition: recent advances from the zebrafish model. F1000Res 2020; 9. [PMID: 32528656 PMCID: PMC7262572 DOI: 10.12688/f1000research.21809.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/17/2020] [Indexed: 01/02/2023] Open
Abstract
Early animal development is characterized by intense reorganization of the embryonic genome, including large-scale changes in chromatin structure and in the DNA and histone modifications that help shape this structure. Particularly profound shifts in the chromatin landscape are associated with the maternal-to-zygotic transition, when the zygotic genome is first transcribed and maternally loaded transcripts are degraded. The accessibility of the early zebrafish embryo facilitates the interrogation of chromatin during this critical window of development, making it an important model for early chromatin regulation. Here, we review our current understanding of chromatin dynamics during early zebrafish development, highlighting new advances as well as similarities and differences between early chromatin regulation in zebrafish and other species.
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Affiliation(s)
| | | | - Mary G Goll
- Department of Genetics, University of Georgia, Athens, GA, USA
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24
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Cytosine Methylation Affects the Mutability of Neighboring Nucleotides in Germline and Soma. Genetics 2020; 214:809-823. [PMID: 32079595 DOI: 10.1534/genetics.120.303028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 02/12/2020] [Indexed: 02/07/2023] Open
Abstract
Methylated cytosines deaminate at higher rates than unmethylated cytosines, and the lesions they produce are repaired less efficiently. As a result, methylated cytosines are mutational hotspots. Here, combining rare polymorphism and base-resolution methylation data in humans, Arabidopsis thaliana, and rice (Oryza sativa), we present evidence that methylation state affects mutation dynamics not only at the focal cytosine but also at neighboring nucleotides. In humans, contrary to prior suggestions, we find that nucleotides in the close vicinity (±3 bp) of methylated cytosines mutate less frequently. Reduced mutability around methylated CpGs is also observed in cancer genomes, considering single nucleotide variants alongside tissue-of-origin-matched methylation data. In contrast, methylation is associated with increased neighborhood mutation risk in A. thaliana and rice. The difference in neighborhood mutation risk is less pronounced further away from the focal CpG and modulated by regional GC content. Our results are consistent with a model where altered risk at neighboring bases is linked to lesion formation at the focal CpG and subsequent long-patch repair. Our findings indicate that cytosine methylation has a broader mutational footprint than is commonly assumed.
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Liu J, Hu H, Panserat S, Marandel L. Evolutionary history of DNA methylation related genes in chordates: new insights from multiple whole genome duplications. Sci Rep 2020; 10:970. [PMID: 31969623 PMCID: PMC6976628 DOI: 10.1038/s41598-020-57753-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 12/20/2019] [Indexed: 01/11/2023] Open
Abstract
DNA methylation is an important epigenetic mechanism involved in many biological processes, i.e. gametogenesis and embryonic development. However, increased copy numbers of DNA methylation related genes (dnmt, tet and tdg) have been found during chordate evolution due to successive whole genome duplication (WGD) events. Their evolutionary history and phylogenetic relationships remain unclear. The present study is the first to clarify the evolutionary history of DNA methylation genes in chordates. In particular, our results highlight the fixation of several dnmt3-related genes following successive WGD throughout evolution. The rainbow trout genome offered a unique opportunity to study the early evolutionary fates of duplicated genes due to a recent round of WGD at the radiation of salmonids. Differences highlighted in transcriptional patterns of these genes during gametogenesis and ontogenesis in trout indicated that they might be subjected to sub- or neo-functionalisation after WDG. The fixation of multiple dnmt3 genes in genomes after WGD could contribute to the diversification and plastic adaptation of the teleost.
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Affiliation(s)
- Jingwei Liu
- INRAE, Univ Pau & Pays de l'Adour, E2S-UPPA, UMR1419 Nutrition Metabolism and Aquaculture, Aquapôle, F-64310, Saint-Pée-sur-Nivelle, France
| | - Huihua Hu
- INRAE, Univ Pau & Pays de l'Adour, E2S-UPPA, UMR1419 Nutrition Metabolism and Aquaculture, Aquapôle, F-64310, Saint-Pée-sur-Nivelle, France
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Stéphane Panserat
- INRAE, Univ Pau & Pays de l'Adour, E2S-UPPA, UMR1419 Nutrition Metabolism and Aquaculture, Aquapôle, F-64310, Saint-Pée-sur-Nivelle, France
| | - Lucie Marandel
- INRAE, Univ Pau & Pays de l'Adour, E2S-UPPA, UMR1419 Nutrition Metabolism and Aquaculture, Aquapôle, F-64310, Saint-Pée-sur-Nivelle, France.
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Seritrakul P, Gross JM. Genetic and epigenetic control of retinal development in zebrafish. Curr Opin Neurobiol 2019; 59:120-127. [PMID: 31255843 PMCID: PMC6888853 DOI: 10.1016/j.conb.2019.05.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/23/2019] [Accepted: 05/28/2019] [Indexed: 12/24/2022]
Abstract
The vertebrate retina is a complex structure composed of seven cell types (six neuron and one glia), and all of which originate from a seemingly homogeneous population of proliferative multipotent retinal progenitor cells (RPCs) that exit the cell cycle and differentiate in a spatio-temporally regulated and stereotyped fashion. This neurogenesis process requires intricate genetic regulation involving a combination of cell intrinsic transcription factors and extrinsic signaling molecules, and many critical factors have been identified that influence the timing and composition of the developing retina. Adding complexity to the process, over the past decade, a variety of epigenetic regulatory mechanisms have been shown to influence neurogenesis, and these include changes in histone modifications and the chromatin landscape and changes in DNA methylation and hydroxymethylation patterns. This review summarizes recent findings in the genetic and epigenetic regulation of retinal development, with an emphasis on the zebrafish model system, and it outlines future areas of investigation that will continue to push the field forward into the epigenomics era.
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Affiliation(s)
- Pawat Seritrakul
- Faculty of Animal Sciences and Agricultural Technology, Silpakorn University, Phetchaburi, 76120, Thailand.
| | - Jeffrey M Gross
- Departments of Ophthalmology, and Developmental Biology, The Louis J. Fox Center for Vision Restoration, The McGowan Institute for Regenerative Medicine, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, United States.
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Balasubramanian S, Raghunath A, Perumal E. Role of epigenetics in zebrafish development. Gene 2019; 718:144049. [DOI: 10.1016/j.gene.2019.144049] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 02/07/2023]
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28
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Schmitz RJ, Lewis ZA, Goll MG. DNA Methylation: Shared and Divergent Features across Eukaryotes. Trends Genet 2019; 35:818-827. [PMID: 31399242 DOI: 10.1016/j.tig.2019.07.007] [Citation(s) in RCA: 132] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/01/2019] [Accepted: 07/15/2019] [Indexed: 02/02/2023]
Abstract
Chemical modification of nucleotide bases in DNA provides one mechanism for conveying information in addition to the genetic code. 5-methylcytosine (5mC) represents the most common chemically modified base in eukaryotic genomes. Sometimes referred to simply as DNA methylation, in eukaryotes 5mC is most prevalent at CpG dinucleotides and is frequently associated with transcriptional repression of transposable elements. However, 5mC levels and distributions are variable across phylogenies, and emerging evidence suggests that the functions of DNA methylation may be more diverse and complex than was previously appreciated. We summarize the current understanding of DNA methylation profiles and functions in different eukaryotic lineages.
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Affiliation(s)
- Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Zachary A Lewis
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Mary G Goll
- Department of Genetics, University of Georgia, Athens, GA 30602, USA.
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Qian Y, Ji C, Yue S, Zhao M. Exposure of low-dose fipronil enantioselectively induced anxiety-like behavior associated with DNA methylation changes in embryonic and larval zebrafish. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 249:362-371. [PMID: 30909129 DOI: 10.1016/j.envpol.2019.03.038] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/11/2019] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
Fipronil, a broad-spectrum chiral insecticide, has been documented to induce significant neurotoxicity to nontarget aquatic species; however, whether its neurotoxicity behaves enantioselectively and what molecular mechanisms correspond to the neurotoxicity remain unanswered. To date, few investigations have focused on the genomic mechanisms responsible for the enantioselective toxicity of chiral pesticides. The epigenetic modifications, especially DNA methylation, caused by the pesticides are also blind spot of the research works. Video tracking showed that R-fipronil exhibited more intense neurotoxicity, as well as the induction of more severe anxiety-like behavior, such as boosted swimming speed and dysregulated photoperiodic locomotion, to embryonic and larval zebrafish compared with S-fipronil. The MeDIP-Seq analysis, combined with Gene Ontology and KEGG, revealed that R-fipronil disrupted five signaling pathways (MAPK, Calcium signaling, Neuroactive ligand-receptor interaction, Purine metabolism, and Endocytosis) to a greater extent than S-fipronil through the hypermethylation of several important neuro-related genes, whereas no significant alterations of global DNA methylation were observed on the two enantiomers. To summarize, our data indicated that the fipronil-conducted enantioselective neurotoxicity likely applied its enantioselectivity by the dysregulation of DNA methylation. Our study also provided novel epigenetic insights into the study of enantioselective biological effects and the relevant underlying mechanisms of chiral insecticide.
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Affiliation(s)
- Yi Qian
- College of Life Science, Taizhou University, Taizhou, Zhejiang, 318000, China
| | - Chenyang Ji
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Siqing Yue
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Meirong Zhao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China.
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Cardoso AL, Fantinatti BEDA, Venturelli NB, Carmello BDO, de Oliveira RA, Martins C. Epigenetic DNA Modifications Are Correlated With B Chromosomes and Sex in the Cichlid Astatotilapia latifasciata. Front Genet 2019; 10:324. [PMID: 31031803 PMCID: PMC6474290 DOI: 10.3389/fgene.2019.00324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/22/2019] [Indexed: 12/11/2022] Open
Abstract
Supernumerary B chromosomes are dispensable elements found in several groups of eukaryotes, and their impacts in host organisms are not clear. The cichlid fish Astatotilapia latifasciata presents one or two large metacentric B chromosomes. These elements affect the transcription of several classes of RNAs. Here, we evaluated the epigenetic DNA modification status of B chromosomes using immunocytogenetics and assessed the impact of B chromosome presence on the global contents of 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) and the molecular mechanisms underlying these variations. We found that the B chromosome of A. latifasciata has an active pattern of DNA epimarks, and its presence promotes the loss of 5mC in gonads of females with B chromosome (FB+) and promotes the loss of 5hmC in the muscle of males with the B element (MB+). Based on the transcriptional quantification of DNA modification genes (dnmt, tet, and tdg) and their candidate regulators (idh genes, microRNAs, and long non-coding RNAs) and on RNA-protein interaction prediction, we suggest the occurrence of passive demethylation in gonads of FB+ and 5hmC loss by Tet inhibition or by 5hmC oxidation in MB+ muscle. We suggest that these results can also explain the previously reported variations in the transcription levels of several classes of RNA depending on B chromosome presence. The DNA modifications detected here are also influenced by sex. Although the correlation between B chromosomes and sex has been previously reported, it remains unexplained. The B chromosome of A. latifasciata seems to be active and impacts cell physiology in a very complex way, including at the epigenetic level.
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Affiliation(s)
- Adauto Lima Cardoso
- Integrative Genomics Laboratory, Department of Morphology, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
| | - Bruno Evaristo de Almeida Fantinatti
- Integrative Genomics Laboratory, Department of Morphology, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
| | - Natália Bortholazzi Venturelli
- Integrative Genomics Laboratory, Department of Morphology, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
| | - Bianca de Oliveira Carmello
- Integrative Genomics Laboratory, Department of Morphology, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
| | - Rogério Antonio de Oliveira
- Department of Biostatistics, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
| | - Cesar Martins
- Integrative Genomics Laboratory, Department of Morphology, Institute of Biosciences, São Paulo State University - Universidade Estadual Paulista, Botucatu, Brazil
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Abstract
In the last decade, the concept of animal stress has been stressed thin to accommodate the effects of short-term changes in cell and tissue physiology, major behavioral syndromes in individuals and ecological disturbances in populations. Seyle's definition of stress as "the nonspecific (common) result of any demand upon the body" now encompasses homeostasis in a broader sense, including all the hierarchical levels in a networked biological system. The heterogeneity of stress responses thus varies within individuals, and stressors become multimodal in terms of typology, source and effects, as well as the responses that each individual elicits to cope with the disturbance. In fish, the time course of changes after stress strongly depends on several factors, including the stressful experiences in early life, the vertical transmission of stressful-prone phenotypes, the degree of individual phenotypic plasticity, the robustness and variety of the epigenetic network related to environmentally induced changes, and the intrinsic behavioral responses (individuality/personality) of each individual. The hierarchical heterogeneity of stress responses demands a code that may decrypt and simplify the analysis of both proximate and evolutionary causes of a particular stress phenotype. We propose an analytical framework, the stressotope, defined as an adaptive scenario dominated by common environmental selective pressures that elicit common multilevel acute stress-induced responses and produce a measurable allostatic load in the organism. The stressotope may constitute a blueprint of embedded interactions between stress-related variations in cell states, molecular mediators and systemic networks, a map of circuits that reflect the inherited and acquired stress responses in an ever-changing, microorganismal-loaded medium. Several features of the proposed model are discussed as a starting point to pin down the maximum common stress responses across immune-neuroendocrine relevant physiological levels and scenarios, including the characterization of behavioral responses, in fish.
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Affiliation(s)
- Joan Carles Balasch
- Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain
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Volgin AD, Yakovlev OA, Demin KA, de Abreu MS, Alekseeva PA, Friend AJ, Lakstygal AM, Amstislavskaya TG, Bao W, Song C, Kalueff AV. Zebrafish models for personalized psychiatry: Insights from individual, strain and sex differences, and modeling gene x environment interactions. J Neurosci Res 2018; 97:402-413. [PMID: 30320468 DOI: 10.1002/jnr.24337] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 08/16/2018] [Accepted: 09/17/2018] [Indexed: 12/30/2022]
Abstract
Currently becoming widely recognized, personalized psychiatry focuses on unique physiological and genetic profiles of patients to best tailor their therapy. However, the role of individual differences, as well as genetic and environmental factors, in human psychiatric disorders remains poorly understood. Animal experimental models are a valuable tool to improve our understanding of disease pathophysiology and its molecular mechanisms. Due to high reproduction capability, fully sequenced genome, easy gene editing, and high genetic and physiological homology with humans, zebrafish (Danio rerio) are emerging as a novel powerful model in biomedicine. Mounting evidence supports zebrafish as a useful model organism in CNS research. Robustly expressed in these fish, individual, strain, and sex differences shape their CNS responses to genetic, environmental, and pharmacological manipulations. Here, we discuss zebrafish as a promising complementary translational tool to further advance patient-centered personalized psychiatry.
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Affiliation(s)
- Andrey D Volgin
- Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia.,Military Medical Academy, St Petersburg, Russia
| | - Oleg A Yakovlev
- Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia.,Military Medical Academy, St Petersburg, Russia
| | - Konstantin A Demin
- Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
| | - Murilo S de Abreu
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, Brazil.,Postgraduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria, Brazil
| | - Polina A Alekseeva
- Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia
| | - Ashton J Friend
- Tulane University School of Science and Engineering, New Orleans, Louisiana
| | - Anton M Lakstygal
- Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
| | - Tamara G Amstislavskaya
- Laboratory of Translational Biopsychiatry, Scientific Research Institute of Physiology and Basic Medicine, Novosibirsk, Russia
| | - Wandong Bao
- School of Pharmacy, Southwest University, Chongqing, China
| | - Cai Song
- Research Institute of Marine Drugs and Nutrition, Guangdong Ocean University, Zhanjiang, China
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Chongqing, China.,Ural Federal University, Ekaterinburg, Russia.,ZENEREI Research Center, Slidell, Louisiana.,Institute of Experimental Medicine, Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Granov Russian Scientific Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.,Scientific Research Institute of Physiology and Basic Medicine, Novosibirsk, Russia.,Laboratory of Biological Psychiatry, Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
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33
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Abstract
Defining the etiology of inflammatory bowel disease (IBD) continues to elude researchers, in part due to the possibility that there may be different triggers for a spectrum of disease phenotypes that are currently classified as either Crohn's disease (CD) or ulcerative colitis (UC). What is clear is that genetic susceptibility plays an important role in the development of IBD, and large genome-wide association studies using case-control approaches have identified more than 230 risk alleles. Many of these identified risk alleles are located in a variety of genes important in host-microbiome interactions. In spite of these major advances, the mechanisms behind the genetic influence on disease development remain unknown. In addition, the identified genetic risks have thus far failed to fully define the hereditability of IBD. Host genetics influence host interactions with the gut microbiota in maintaining health through a balance of regulated immune responses and coordinated microbial composition and function. What remains to be defined is how alterations in these interactions can lead to disease. The nature and cause of changes in the microbiota in patients with IBD are poorly understood. In spite of the large catalog of alterations in the microbiota of IBD patients, inflammation itself can alter the microbiota, leaving open the question of which is cause or effect. The composition and function of the gut microbiota are influenced by many factors, including environmental factors, dietary factors, and, as recent studies have shown, host genetic makeup. More than 200 loci have shown potential to influence the microbiota, but replication and larger studies are still required to validate these findings. It would seem reasonable to consider the combination of both host genetic makeup and the inheritance of the microbiota as interdependent heritable forces that could explain the nature of an individual's susceptibility to IBD or indeed the actual cause of IBD. In this review, we will consider the contribution of the host genetics, the microbiome, and the influence of host genetics on the microbiota to the heritability of IBD.
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Affiliation(s)
- Williams Turpin
- Zane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Medicine and Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Ashleigh Goethel
- Department of Medicine and Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Larbi Bedrani
- Zane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Medicine and Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Kenneth Croitoru, MDCM
- Zane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Medicine and Immunology, University of Toronto, Toronto, Ontario, Canada
- Correspondence: Kenneth Croitoru, Zane Cohen Centre for Digestive Diseases, Division of Gastroenterology, Department of Medicine and Immunology, University of Toronto, Mount Sinai Hospital, 600 University Avenue Room 437, Toronto, Ontario, M5G 1X5, Canada ()
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Jessop P, Ruzov A, Gering M. Developmental Functions of the Dynamic DNA Methylome and Hydroxymethylome in the Mouse and Zebrafish: Similarities and Differences. Front Cell Dev Biol 2018; 6:27. [PMID: 29616219 PMCID: PMC5869911 DOI: 10.3389/fcell.2018.00027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 03/05/2018] [Indexed: 12/25/2022] Open
Abstract
5-methylcytosine (5mC) is the best understood DNA modification and is generally believed to be associated with repression of gene expression. Over the last decade, sequentially oxidized forms of 5mC (oxi-mCs) have been discovered within the genomes of vertebrates. Their discovery was accompanied by that of the ten-eleven translocation (TET) methylcytosine dioxygenases, the enzymes that catalyze the formation of the oxi-mCs. Although a number of studies performed on different vertebrate models and embryonic stem cells demonstrated that both TET enzymes and oxi-mCs are likely to be important for several developmental processes it is currently unclear whether their developmental roles are conserved among vertebrates. Here, we summarize recent developments in this field suggesting that biological roles of TETs/oxi-mCs may significantly differ between mice and zebrafish. Thus, although the role of TET proteins in late organogenesis has been documented for both these systems; unlike in mice the enzymatic oxidation of 5mC does not seem to be involved in zygotic reprogramming or gastrulation in zebrafish. Our analysis may provide an insight into the general principles of epigenetic regulation of animal development and cellular differentiation.
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Affiliation(s)
- Peter Jessop
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Alexey Ruzov
- Division of Cancer and Stem Cells, Centre for Biomolecular Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Martin Gering
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
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35
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Epigenetics in teleost fish: From molecular mechanisms to physiological phenotypes. Comp Biochem Physiol B Biochem Mol Biol 2018; 224:210-244. [PMID: 29369794 DOI: 10.1016/j.cbpb.2018.01.006] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 01/08/2018] [Accepted: 01/16/2018] [Indexed: 02/07/2023]
Abstract
While the field of epigenetics is increasingly recognized to contribute to the emergence of phenotypes in mammalian research models across different developmental and generational timescales, the comparative biology of epigenetics in the large and physiologically diverse vertebrate infraclass of teleost fish remains comparatively understudied. The cypriniform zebrafish and the salmoniform rainbow trout and Atlantic salmon represent two especially important teleost orders, because they offer the unique possibility to comparatively investigate the role of epigenetic regulation in 3R and 4R duplicated genomes. In addition to their sequenced genomes, these teleost species are well-characterized model species for development and physiology, and therefore allow for an investigation of the role of epigenetic modifications in the emergence of physiological phenotypes during an organism's lifespan and in subsequent generations. This review aims firstly to describe the evolution of the repertoire of genes involved in key molecular epigenetic pathways including histone modifications, DNA methylation and microRNAs in zebrafish, rainbow trout, and Atlantic salmon, and secondly, to discuss recent advances in research highlighting a role for molecular epigenetics in shaping physiological phenotypes in these and other teleost models. Finally, by discussing themes and current limitations of the emerging field of teleost epigenetics from both theoretical and technical points of view, we will highlight future research needs and discuss how epigenetics will not only help address basic research questions in comparative teleost physiology, but also inform translational research including aquaculture, aquatic toxicology, and human disease.
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36
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Cavalieri V, Spinelli G. Environmental epigenetics in zebrafish. Epigenetics Chromatin 2017; 10:46. [PMID: 28982377 PMCID: PMC5629768 DOI: 10.1186/s13072-017-0154-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/27/2017] [Indexed: 02/06/2023] Open
Abstract
It is widely accepted that the epigenome can act as the link between environmental cues, both external and internal, to the organism and phenotype by converting the environmental stimuli to phenotypic responses through changes in gene transcription outcomes. Environmental stress endured by individual organisms can also enforce epigenetic variations in offspring that had never experienced it directly, which is termed transgenerational inheritance. To date, research in the environmental epigenetics discipline has used a wide range of both model and non-model organisms to elucidate the various epigenetic mechanisms underlying the adaptive response to environmental stimuli. In this review, we discuss the advantages of the zebrafish model for studying how environmental toxicant exposures affect the regulation of epigenetic processes, especially DNA methylation, which is the best-studied epigenetic mechanism. We include several very recent studies describing the state-of-the-art knowledge on this topic in zebrafish, together with key concepts in the function of DNA methylation during vertebrate embryogenesis.
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Affiliation(s)
- Vincenzo Cavalieri
- Laboratory of Molecular Biology and Functional Genomics, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze Edificio 16, 90128, Palermo, Italy. .,Zebrafish Laboratory, Advanced Technologies Network (ATeN) Center, University of Palermo, Viale delle Scienze Edificio 18, 90128, Palermo, Italy.
| | - Giovanni Spinelli
- Laboratory of Molecular Biology and Functional Genomics, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze Edificio 16, 90128, Palermo, Italy.
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37
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Firmino J, Carballo C, Armesto P, Campinho MA, Power DM, Manchado M. Phylogeny, expression patterns and regulation of DNA Methyltransferases in early development of the flatfish, Solea senegalensis. BMC DEVELOPMENTAL BIOLOGY 2017; 17:11. [PMID: 28716037 PMCID: PMC5513168 DOI: 10.1186/s12861-017-0154-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 07/06/2017] [Indexed: 12/12/2022]
Abstract
Background The identification of DNA methyltransferases (Dnmt) expression patterns during development and their regulation is important to understand the epigenetic mechanisms that modulate larval plasticity in marine fish. In this study, dnmt1 and dnmt3 paralogs were identified in the flatfish Solea senegalensis and expression patterns in early developmental stages and juveniles were determined. Additionally, the regulation of Dnmt transcription by a specific inhibitor (5-aza-2′-deoxycytidine) and temperature was evaluated. Results Five paralog genes of dnmt3, namely dnmt3aa, dnmt3ab, dnmt3ba, dnmt3bb.1 and dnmt3bb.2 and one gene for dnmt1 were identified. Phylogenetic analysis revealed that the dnmt gene family was highly conserved in teleosts and three fish-specific genes, dnmt3aa, dnmt3ba and dnmt3bb.2 have evolved. The spatio-temporal expression patterns of four dnmts (dnmt1, dnmt3aa, dnmt3ab and dnmt3bb.1) were different in early larval stages although all of them reduced expression with the age and were detected in neural organs and dnmt3aa appeared specific to somites. In juveniles, the four dnmt genes were expressed in brain and hematopoietic tissues such as kidney, spleen and gills. Treatment of sole embryos with 5-aza-2′-deoxycytidine down-regulated dntm1 and up-regulated dntm3aa. Moreover, in lecithotrophic larval stages, dnmt3aa and dnmt3ab were temperature sensitive and their expression was higher in larvae incubated at 16 °C relative to 20 °C. Conclusion Five dnmt3 and one dnmt1 paralog were identified in sole and their distinct developmental and tissue-specific expression patterns indicate that they may have different roles during development. The inhibitor 5-aza-2′-deoxycytidine modified the transcript abundance of dntm1 and dntm3aa in embryos, which suggests that a regulatory feedback mechanism exists for these genes. The impact of thermal regime on expression levels of dnmt3aa and dnmt3ab in lecithotrophic larval stages suggests that these paralogs might be involved in thermal programing. Electronic supplementary material The online version of this article (doi:10.1186/s12861-017-0154-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joana Firmino
- IFAPA Centro El Toruño, Junta de Andalucía, Camino Tiro Pichón s/n, 11500 El Puerto de Santa María, Cádiz, Spain.,Comparative Molecular Endocrinology Group, Marine Science Centre (CCMAR), Universidade do Algarve, 8005-139, Faro, Portugal
| | - Carlos Carballo
- IFAPA Centro El Toruño, Junta de Andalucía, Camino Tiro Pichón s/n, 11500 El Puerto de Santa María, Cádiz, Spain
| | - Paula Armesto
- IFAPA Centro El Toruño, Junta de Andalucía, Camino Tiro Pichón s/n, 11500 El Puerto de Santa María, Cádiz, Spain
| | - Marco A Campinho
- Comparative Molecular Endocrinology Group, Marine Science Centre (CCMAR), Universidade do Algarve, 8005-139, Faro, Portugal
| | - Deborah M Power
- Comparative Molecular Endocrinology Group, Marine Science Centre (CCMAR), Universidade do Algarve, 8005-139, Faro, Portugal
| | - Manuel Manchado
- IFAPA Centro El Toruño, Junta de Andalucía, Camino Tiro Pichón s/n, 11500 El Puerto de Santa María, Cádiz, Spain.
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Abstract
Zebrafish have been extensively used for studying vertebrate development and modeling human diseases such as cancer. In the last two decades, they have also emerged as an important model for developmental toxicology research and, more recently, for studying the developmental origins of health and disease (DOHaD). It is widely recognized that epigenetic mechanisms mediate the persistent effects of exposure to chemicals during sensitive windows of development. There is considerable interest in understanding the epigenetic mechanisms associated with DOHaD using zebrafish as a model system. This review summarizes our current knowledge on the effects of environmental chemicals on DNA methylation, histone modifications and noncoding RNAs in the context of DOHaD, and suggest some key considerations in designing experiments for characterizating the mechanisms of action.
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Affiliation(s)
- Neelakanteswar Aluru
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
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39
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He Y, Bao B, Li H. Using zebrafish as a model to study the role of epigenetics in hearing loss. Expert Opin Drug Discov 2017; 12:967-975. [PMID: 28682135 DOI: 10.1080/17460441.2017.1340270] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION The rapid progress of bioinformatics and high-throughput screening techniques in recent years has led to the identification of many candidate genes and small-molecule drugs that have the potential to make significant contributions to our understanding of the developmental and pathological processes of hearing, but it remains unclear how these genes and regulatory factors are coordinated. Increasing evidence suggests that epigenetic mechanisms are essential for establishing gene expression profiles and likely play an important role in the development of inner ear and in the pathology of hearing-associated diseases. Zebrafish are a valuable and tractable in vivo model organism for monitoring changes in the epigenome and for identifying new epigenetic processes and drug molecules that can influence vertebrate development. Areas covered: In this review, the authors focus on zebrafish as a model to summarize recent findings concerning the roles of epigenetics in the development, regeneration, and protection of hair cells. Expert opinion: Using the zebrafish model in combination with high-throughput screening and genome-editing technologies to investigate the function of epigenetics in hearing is crucial to help us better understand the molecular and genetic mechanisms of auditory development and function. It will also contribute to the development of new strategies to restore hearing loss.
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Affiliation(s)
- Yingzi He
- a ENT Institute and Otorhinolaryngology Department of Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology , Fudan University , Shanghai , China.,c Key Laboratory of Hearing Medicine of NHFPC , Shanghai , China
| | - Beier Bao
- a ENT Institute and Otorhinolaryngology Department of Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology , Fudan University , Shanghai , China
| | - Huawei Li
- a ENT Institute and Otorhinolaryngology Department of Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology , Fudan University , Shanghai , China.,b Institutes of Biomedical Sciences , Fudan University , Shanghai , China.,c Key Laboratory of Hearing Medicine of NHFPC , Shanghai , China.,d Shanghai Engineering Research Centre of Cochlear Implant , Shanghai , China.,e The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science , Fudan University , Shanghai , China
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40
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Wang Y, Liu H, Sun Z. Lamarck rises from his grave: parental environment-induced epigenetic inheritance in model organisms and humans. Biol Rev Camb Philos Soc 2017; 92:2084-2111. [PMID: 28220606 DOI: 10.1111/brv.12322] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 01/12/2017] [Accepted: 01/18/2017] [Indexed: 12/12/2022]
Abstract
Organisms can change their physiological/behavioural traits to adapt and survive in changed environments. However, whether these acquired traits can be inherited across generations through non-genetic alterations has been a topic of debate for over a century. Emerging evidence indicates that both ancestral and parental experiences, including nutrition, environmental toxins, nurturing behaviour, and social stress, can have powerful effects on the physiological, metabolic and cellular functions in an organism. In certain circumstances, these effects can be transmitted across several generations through epigenetic (i.e. non-DNA sequence-based rather than mutational) modifications. In this review, we summarize recent evidence on epigenetic inheritance from parental environment-induced developmental and physiological alterations in nematodes, fruit flies, zebrafish, rodents, and humans. The epigenetic modifications demonstrated to be both susceptible to modulation by environmental cues and heritable, including DNA methylation, histone modification, and small non-coding RNAs, are also summarized. We particularly focus on evidence that parental environment-induced epigenetic alterations are transmitted through both the maternal and paternal germlines and exert sex-specific effects. The thought-provoking data presented here raise fundamental questions about the mechanisms responsible for these phenomena. In particular, the means that define the specificity of the response to parental experience in the gamete epigenome and that direct the establishment of the specific epigenetic change in the developing embryos, as well as in specific tissues in the descendants, remain obscure and require elucidation. More precise epigenetic assessment at both the genome-wide level and single-cell resolution as well as strategies for breeding at relatively sensitive periods of development and manipulation aimed at specific epigenetic modification are imperative for identifying parental environment-induced epigenetic marks across generations. Considering their diverse epigenetic architectures, the conservation and prevalence of the mechanisms underlying epigenetic inheritance in non-mammals require further investigation in mammals. Interpretation of the consequences arising from epigenetic inheritance on organisms and a better understanding of the underlying mechanisms will provide insight into how gene-environment interactions shape developmental processes and physiological functions, which in turn may have wide-ranging implications for human health, and understanding biological adaptation and evolution.
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Affiliation(s)
- Yan Wang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Huijie Liu
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou 325000, China
| | - Zhongsheng Sun
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China.,Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou 325000, China
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41
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Hoang TV, Horowitz ER, Chaffee BR, Qi P, Flake RE, Bruney DG, Rasor BJ, Rosalez SE, Wagner BD, Robinson ML. Lens development requires DNMT1 but takes place normally in the absence of both DNMT3A and DNMT3B activity. Epigenetics 2017; 12:27-40. [PMID: 27824296 PMCID: PMC5270636 DOI: 10.1080/15592294.2016.1253651] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/14/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022] Open
Abstract
Despite the wealth of knowledge of transcription factors involved in lens development, little information exists about the role of DNA methylation in this process. Here, we investigated the role of DNA methylation in lens development and fiber cell differentiation using mice conditionally lacking maintenance or de novo methyltransferases in the lens lineage. We found that while Dnmt1 inactivation at the lens placode stage (via the Le-Cre transgene) led to lens DNA hypomethylation and severe lens epithelial apoptosis, lens fiber cell differentiation remained largely unaffected. The simultaneous deletion of phosphatase and tensin homolog (Pten) elevated the level of phosphorylated AKT and rescued many of the morphological defects and cell death in DNMT1-deficient lenses. With a different Cre driver (MLR10) we demonstrated that a small number of lens epithelial cells escaped Dnmt1-deletion and over-proliferated to compensate for the loss of Dnmt1-deleted cells, suggesting that lens epithelium possess a substantial capacity for self-renewal. Unlike lenses deficient for Dnmt1, inactivation of both Dnmt3a and Dnmt3b by either the Le-Cre or MLR10-Cre transgene did not result in any obvious lens phenotype prior to 10 months of age. Taken together, while lens epithelial cell survival requires DNMT1, morphologically normal lenses develop in the absence of both DNMT3A and DNMT3B.
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Affiliation(s)
- Thanh V. Hoang
- Department of Biology, Miami University, Oxford, OH, USA
| | | | | | - Peipei Qi
- Department of Biology, Miami University, Oxford, OH, USA
| | | | | | - Blake J. Rasor
- Department of Biology, Miami University, Oxford, OH, USA
| | | | - Brad D. Wagner
- Department of Biology, Miami University, Oxford, OH, USA
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42
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Kong EY, Cheng SH, Yu KN. Zebrafish as an In Vivo Model to Assess Epigenetic Effects of Ionizing Radiation. Int J Mol Sci 2016; 17:ijms17122108. [PMID: 27983682 PMCID: PMC5187908 DOI: 10.3390/ijms17122108] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 12/01/2016] [Accepted: 12/09/2016] [Indexed: 12/14/2022] Open
Abstract
Exposure to ionizing radiations (IRs) is ubiquitous in our environment and can be categorized into “targeted” effects and “non-targeted” effects. In addition to inducing deoxyribonucleic acid (DNA) damage, IR exposure leads to epigenetic alterations that do not alter DNA sequence. Using an appropriate model to study the biological effects of radiation is crucial to better understand IR responses as well as to develop new strategies to alleviate exposure to IR. Zebrafish, Danio rerio, is a scientific model organism that has yielded scientific advances in several fields and recent studies show the usefulness of this vertebrate model in radiation biology. This review briefly describes both “targeted” and “non-targeted” effects, describes the findings in radiation biology using zebrafish as a model and highlights the potential of zebrafish to assess the epigenetic effects of IR, including DNA methylation, histone modifications and miRNA expression. Other in vivo models are included to compare observations made with zebrafish, or to illustrate the feasibility of in vivo models when the use of zebrafish was unavailable. Finally, tools to study epigenetic modifications in zebrafish, including changes in genome-wide DNA methylation, histone modifications and miRNA expression, are also described in this review.
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Affiliation(s)
- Eva Yi Kong
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, China.
| | - Shuk Han Cheng
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
- State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong, China.
| | - Kwan Ngok Yu
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, China.
- State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong, China.
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43
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Dorts J, Falisse E, Schoofs E, Flamion E, Kestemont P, Silvestre F. DNA methyltransferases and stress-related genes expression in zebrafish larvae after exposure to heat and copper during reprogramming of DNA methylation. Sci Rep 2016; 6:34254. [PMID: 27731414 PMCID: PMC5059630 DOI: 10.1038/srep34254] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/08/2016] [Indexed: 12/23/2022] Open
Abstract
DNA methylation, a well-studied epigenetic mark, is important for gene regulation in adulthood and for development. Using genetic and epigenetic approaches, the present study aimed at evaluating the effects of heat stress and copper exposure during zebrafish early embryogenesis when patterns of DNA methylation are being established, a process called reprogramming. Embryos were exposed to 325 μg Cu/L from fertilization (<1 h post fertilization - hpf) to 4 hpf at either 26.5 °C or 34 °C, followed by incubation in clean water at 26.5 °C till 96 hpf. Significant increased mortality rates and delayed hatching were observed following exposure to combined high temperature and Cu. Secondly, both stressors, alone or in combination, significantly upregulated the expression of de novo DNA methyltransferase genes (dnmt3) along with no differences in global cytosine methylation level. Finally, Cu exposure significantly increased the expression of metallothionein (mt2) and heat shock protein (hsp70), the latter being also increased following exposure to high temperature. These results highlighted the sensitivity of early embryogenesis and more precisely of the reprogramming period to environmental challenges, in a realistic situation of combined stressors.
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Affiliation(s)
- Jennifer Dorts
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Elodie Falisse
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Emilie Schoofs
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Enora Flamion
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Patrick Kestemont
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Frédéric Silvestre
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium
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44
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Metzger DCH, Schulte PM. Epigenomics in marine fishes. Mar Genomics 2016; 30:43-54. [PMID: 26833273 DOI: 10.1016/j.margen.2016.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 01/20/2016] [Accepted: 01/21/2016] [Indexed: 12/31/2022]
Abstract
Epigenetic mechanisms are an underappreciated and often ignored component of an organism's response to environmental change and may underlie many types of phenotypic plasticity. Recent technological advances in methods for detecting epigenetic marks at a whole-genome scale have launched new opportunities for studying epigenomics in ecologically relevant non-model systems. The study of ecological epigenomics holds great promise to better understand the linkages between genotype, phenotype, and the environment and to explore mechanisms of phenotypic plasticity. The many attributes of marine fish species, including their high diversity, variable life histories, high fecundity, impressive plasticity, and economic value provide unique opportunities for studying epigenetic mechanisms in an environmental context. To provide a primer on epigenomic research for fish biologists, we start by describing fundamental aspects of epigenetics, focusing on the most widely studied and most well understood of the epigenetic marks: DNA methylation. We then describe the techniques that have been used to investigate DNA methylation in marine fishes to date and highlight some new techniques that hold great promise for future studies. Epigenomic research in marine fishes is in its early stages, so we first briefly discuss what has been learned about the establishment, maintenance, and function of DNA methylation in fishes from studies in zebrafish and then summarize the studies demonstrating the pervasive effects of the environment on the epigenomes of marine fishes. We conclude by highlighting the potential for ongoing research on the epigenomics of marine fishes to reveal critical aspects of the interaction between organisms and their environments.
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Affiliation(s)
- David C H Metzger
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Patricia M Schulte
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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45
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Aluru N, Kuo E, Helfrich LW, Karchner SI, Linney EA, Pais JE, Franks DG. Developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin alters DNA methyltransferase (dnmt) expression in zebrafish (Danio rerio). Toxicol Appl Pharmacol 2015; 284:142-51. [PMID: 25732252 DOI: 10.1016/j.taap.2015.02.016] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 02/09/2015] [Accepted: 02/13/2015] [Indexed: 01/14/2023]
Abstract
DNA methylation is one of the most important epigenetic modifications involved in the regulation of gene expression. The DNA methylation reaction is catalyzed by DNA methyltransferases (DNMTs). Recent studies have demonstrated that toxicants can affect normal development by altering DNA methylation patterns, but the mechanisms of action are poorly understood. Hence, we tested the hypothesis that developmental exposure to TCDD affects dnmt gene expression patterns. Zebrafish embryos were exposed to 5nM TCDD for 1h from 4 to 5h post-fertilization (hpf) and sampled at 12, 24, 48, 72, and 96 hpf to determine dnmt gene expression and DNA methylation patterns. We performed a detailed analysis of zebrafish dnmt gene expression during development and in adult tissues. Our results demonstrate that dnmt3b genes are highly expressed in early stages of development, and dnmt3a genes are more abundant in later stages. TCDD exposure upregulated dnmt1 and dnmt3b2 expression, whereas dnmt3a1, 3b1, and 3b4 are downregulated following exposure. We did not observe any TCDD-induced differences in global methylation or hydroxymethylation levels, but the promoter methylation of aryl hydrocarbon receptor (AHR) target genes was altered. In TCDD-exposed embryos, AHR repressor a (ahrra) and c-fos promoters were differentially methylated. To characterize the TCDD effects on DNMTs, we cloned the dnmt promoters with xenobiotic response elements and conducted AHR transactivation assays using a luciferase reporter system. Our results suggest that ahr2 can regulate dnmt3a1, dnmt3a2, and dnmt3b2 expression. Overall, we demonstrate that developmental exposure to TCDD alters dnmt expression and DNA methylation patterns.
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Affiliation(s)
- Neelakanteswar Aluru
- Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
| | - Elaine Kuo
- Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA; Stanford University, 450 Serra Mall, Stanford, CA 94305, USA
| | - Lily W Helfrich
- Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA; Northwestern University, 633 Clark St, Evanston, IL 60208, USA
| | - Sibel I Karchner
- Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Elwood A Linney
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Box 3020, Durham, NC 27710, USA
| | - June E Pais
- New England Biolabs, 240 County Road, Ipswich, MA 01938, USA
| | - Diana G Franks
- Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
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46
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Chatterjee A, Stockwell PA, Horsfield JA, Morison IM, Nakagawa S. Base-resolution DNA methylation landscape of zebrafish brain and liver. GENOMICS DATA 2014; 2:342-4. [PMID: 26484126 PMCID: PMC4535936 DOI: 10.1016/j.gdata.2014.10.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 10/07/2014] [Indexed: 01/29/2023]
Abstract
Zebrafish (Danio rerio) is a vertebrate model organism that is widely used for studying a plethora of biological questions, including developmental processes, effects of external cues on phenotype, and human disease modeling. DNA methylation is an important epigenetic mechanism that contributes to gene regulation, and is prevalent in all vertebrates. Reduced representation bisulfite sequencing (RRBS) is a cost-effective technique to generate genome-wide DNA methylation maps and has been used in mammalian genomes (e.g., human, mouse and rat) but not in zebrafish. High-resolution DNA methylation data in zebrafish are limited: increased availability of such data will enable us to model and better understand the roles, causes and consequences of changes in DNA methylation. Here we present five high-resolution DNA methylation maps for wild-type zebrafish brain (two pooled male and two pooled female methylomes) and liver. These data were generated using the RRBS technique (includes 1.43 million CpG sites of zebrafish genome) on the Illumina HiSeq platform. Alignment to the reference genome was performed using the Zv9 genome assembly. To our knowledge, these datasets are the only RRBS datasets and base-resolution DNA methylation data available at this time for zebrafish brain and liver. These datasets could serve as a resource for future studies to document the functional role of DNA methylation in zebrafish. In addition, these datasets could be used as controls while performing analysis on treated samples.
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Affiliation(s)
- Aniruddha Chatterjee
- Department of Pathology, Dunedin School of Medicine, University of Otago, 270 Great King Street, Dunedin 9054, New Zealand ; Gravida: National Centre for Growth and Development, 85 Park Road, Grafton, Auckland 1142, New Zealand
| | - Peter A Stockwell
- Department of Biochemistry, University of Otago, 710 Cumberland Street, Dunedin 9054, New Zealand ; Otago Genomics and Bioinformatics Facility, Centre for Innovation, 87 St David Street, Dunedin 9016, New Zealand
| | - Julia A Horsfield
- Department of Pathology, Dunedin School of Medicine, University of Otago, 270 Great King Street, Dunedin 9054, New Zealand ; Gravida: National Centre for Growth and Development, 85 Park Road, Grafton, Auckland 1142, New Zealand
| | - Ian M Morison
- Department of Pathology, Dunedin School of Medicine, University of Otago, 270 Great King Street, Dunedin 9054, New Zealand ; Gravida: National Centre for Growth and Development, 85 Park Road, Grafton, Auckland 1142, New Zealand
| | - Shinichi Nakagawa
- Gravida: National Centre for Growth and Development, 85 Park Road, Grafton, Auckland 1142, New Zealand ; Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9054, New Zealand
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47
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Seritrakul P, Gross JM. Expression of the de novo DNA methyltransferases (dnmt3 - dnmt8) during zebrafish lens development. Dev Dyn 2013; 243:350-6. [PMID: 24123478 DOI: 10.1002/dvdy.24077] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 09/10/2013] [Accepted: 10/03/2013] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND De novo DNA methylation is thought to be critical for cellular reprogramming during tissue differentiation and development. Little is known about the roles of de novo DNA methylation during eye development, and particularly during lens development. The lens is composed of lens epithelial (LE) and lens fiber (LF) cells, with proliferative LE cells giving rise to differentiated LFs at the "transition zone." Given the unique architecture and developmental program of the lens, and the involvement of de novo DNA methylation during differentiation events in other tissues, we sought to identify de novo DNA methyltransferases expressed in the zebrafish lens. RESULTS Zebrafish possess six de novo DNA methyltransferase genes, dnmt3 - dnmt8. At 24 hr postfertilization (hpf), all six are expressed ubiquitously throughout the eye. By 72 hpf, dnmt3 and dnmt5 become restricted to cells of the retinal ciliary marginal zone (CMZ), dnmt4 and dnmt7 to cells of the CMZ and LE, and dnmt6 and dnmt8 to ganglion cells and cells of the inner nuclear layer of the retina. CONCLUSIONS These data identify regions of the eye where de novo methyltransferases could mediate DNA methylation events during development. Overlapping expression domains also suggest functional redundancy within this gene family in the eye.
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Affiliation(s)
- Pawat Seritrakul
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas
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48
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Stapel LC, Vastenhouw NL. Message control in developmental transitions; deciphering chromatin's role using zebrafish genomics. Brief Funct Genomics 2013; 13:106-20. [PMID: 24170706 DOI: 10.1093/bfgp/elt045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Now that the sequencing of genomes has become routine, understanding how a given genome is used in different ways to obtain cell type diversity in an organism is the next frontier. How specific transcription programs are established during vertebrate embryogenesis, however, remains poorly understood. Transcription is influenced by chromatin structure, which determines the accessibility of DNA-binding proteins to the genome. Although large-scale genomics approaches have uncovered specific features of chromatin structure that are diagnostic for different cell types and developmental stages, our functional understanding of chromatin in transcriptional regulation during development is very limited. In recent years, zebrafish embryogenesis has emerged as an excellent vertebrate model system to investigate the functional relationship between chromatin organization, gene regulation and development in a dynamic environment. Here, we review how studies in zebrafish have started to improve our understanding of the role of chromatin structure in genome activation and pluripotency and in the potential inheritance of transcriptional states from parent to progeny.
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Affiliation(s)
- L Carine Stapel
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, D-01307 Dresden, Germany.
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49
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Rexroad CE, Vallejo RL, Liu S, Palti Y, Weber GM. Quantitative trait loci affecting response to crowding stress in an F(2) generation of rainbow trout produced through phenotypic selection. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2013; 15:613-627. [PMID: 23709047 DOI: 10.1007/s10126-013-9512-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/09/2013] [Indexed: 06/02/2023]
Abstract
Selective breeding programs for salmonids typically aim to improve traits associated with growth and disease resistance. It has been established that stressors common to production environments can adversely affect these and other traits which are important to producers and consumers. Previously, we employed phenotypic selection to create families that exhibit high or low plasma cortisol concentrations in response to crowding stress. Subsequent crosses of high × low phenotypes founded a multigenerational breeding scheme with the aim of dissecting the genetic basis for variation underlying stress response through the identification of quantitative trait loci (QTL). Multiple methods of QTL analyses differing in their assumptions of homozygosity of the causal alleles in the grandparental generation yielded similar results in the F1 generation, and the analysis of two stress response phenotype measurement indexes were highly correlated. In the current study, we conducted a genome scan with microsatellites to detect QTL in the F2 generation of two families created through phenotypic selection and having larger numbers of offspring than families screened in the previous generation. Seven suggestive and three significant QTL were detected, seven of which were not previously detected in the National Center for Cool and Cold Water Aquaculture germplasm, bringing the total number of chromosomes containing significant and suggestive stress response QTL to 4 and 15, respectively. One significant QTL which peaks at 7 cM on chromosome Omy12 spans 12 cM and explains 25 % of the phenotypic variance in family 2008052 particularly warrants further investigation. Five QTL with significant parent-of-origin effects were detected in family 2008052, including two QTL on Omy12. The 95 % confidence intervals for the remaining QTL we detected were broad, requiring validation and fine mapping with other genotyping approaches and mapping strategies. These results will facilitate identification of potential casual alleles that can be employed in strategies aimed at better understanding the genetic and physiological basis of stress responses to crowding in rainbow trout aquaculture production.
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Affiliation(s)
- Caird E Rexroad
- USDA/ARS National Center for Cool and Cold Water Aquaculture, 11861 Leetown Road, Kearneysville, WV 25430, USA.
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Abstract
The zebrafish is a recent addition to animal models of human cancer, and studies using this model are rapidly contributing major insights. Zebrafish develop cancer spontaneously, after mutagen exposure and through transgenesis. The tumours resemble human cancers at the histological, gene expression and genomic levels. The ability to carry out in vivo imaging, chemical and genetic screens, and high-throughput transgenesis offers a unique opportunity to functionally characterize the cancer genome. Moreover, increasingly sophisticated modelling of combinations of genetic and epigenetic alterations will allow the zebrafish to complement what can be achieved in other models, such as mouse and human cell culture systems.
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Affiliation(s)
- Richard White
- Cancer Biology and Genetics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
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