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A small set of differentially expressed genes was associated with two color morphs in natural populations of the pea aphid Acyrthosiphon pisum. Gene 2018; 651:23-32. [DOI: 10.1016/j.gene.2018.01.079] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 01/09/2018] [Accepted: 01/23/2018] [Indexed: 12/11/2022]
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202
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Weyrich A, Jeschek M, Schrapers KT, Lenz D, Chung TH, Rübensam K, Yasar S, Schneemann M, Ortmann S, Jewgenow K, Fickel J. Diet changes alter paternally inherited epigenetic pattern in male Wild guinea pigs. ENVIRONMENTAL EPIGENETICS 2018; 4:dvy011. [PMID: 29992049 PMCID: PMC6031029 DOI: 10.1093/eep/dvy011] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/19/2018] [Accepted: 04/06/2018] [Indexed: 05/14/2023]
Abstract
Epigenetic modifications, of which DNA methylation is the most stable, are a mechanism conveying environmental information to subsequent generations via parental germ lines. The paternal contribution to adaptive processes in the offspring might be crucial, but has been widely neglected in comparison to the maternal one. To address the paternal impact on the offspring's adaptability to changes in diet composition, we investigated if low protein diet (LPD) in F0 males caused epigenetic alterations in their subsequently sired sons. We therefore fed F0 male Wild guinea pigs with a diet lowered in protein content (LPD) and investigated DNA methylation in sons sired before and after their father's LPD treatment in both, liver and testis tissues. Our results point to a 'heritable epigenetic response' of the sons to the fathers' dietary change. Because we detected methylation changes also in the testis tissue, they are likely to be transmitted to the F2 generation. Gene-network analyses of differentially methylated genes in liver identified main metabolic pathways indicating a metabolic reprogramming ('metabolic shift'). Epigenetic mechanisms, allowing an immediate and inherited adaptation may thus be important for the survival of species in the context of a persistently changing environment, such as climate change.
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Affiliation(s)
- A Weyrich
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - M Jeschek
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
- Berlin Center for Genomics in Biodiversity Research, Koenigin-Luise-Street 6-8, 14195 Berlin, Germany
| | - K T Schrapers
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - D Lenz
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - T H Chung
- Zymoresearch, EpiQuest, 17062 Murphy Avenue, Irvine, CA 92614, USA
| | - K Rübensam
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - S Yasar
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - M Schneemann
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - S Ortmann
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - K Jewgenow
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
| | - J Fickel
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Street 17, D-10315 Berlin, Germany
- Institute for Biochemistry and Biology, Potsdam University, Karl-Liebknecht-Street 24-25, 14476 Potsdam, Germany
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203
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Herb BR, Shook MS, Fields CJ, Robinson GE. Defense against territorial intrusion is associated with DNA methylation changes in the honey bee brain. BMC Genomics 2018; 19:216. [PMID: 29580210 PMCID: PMC5870497 DOI: 10.1186/s12864-018-4594-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 03/12/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Aggression is influenced by individual variation in temperament as well as behavioral plasticity in response to adversity. DNA methylation is stably maintained over time, but also reversible in response to specific environmental conditions, and may thus be a neuromolecular regulator of both of these processes. A previous study reported DNA methylation differences between aggressive Africanized and gentle European honey bees. We investigated whether threat-induced aggression altered DNA methylation profiles in the honey bee brain in response to a behavioral stimulus (aggression-provoking intruder bee or inert control). We sampled five minutes and two hours after stimulus exposure to examine the effect of time on epigenetic profiles of aggression. RESULTS There were DNA methylation differences between aggressive and control bees for individual cytosine-guanine dinucleotides (CpGs) across the genome. Eighteen individual CpG sites showed significant difference between aggressive and control bees 120 min post stimulus. For clusters of CpGs, we report four genomic regions differentially methylated between aggressive and control bees at the 5-min time point, and 50 regions differentially methylated at the120-minute time point following intruder exposure. Differential methylation occurred at genes involved in neural plasticity, chromatin remodeling and hormone signaling. Additionally, there was a significant overlap of differential methylation with previously published epigenetic differences that distinguish aggressive Africanized and gentle European honey bees, suggesting an evolutionarily conserved use of brain DNA methylation in the regulation of aggression. Lastly, we identified individually statistically suggestive CpGs that as a group were significantly associated with differentially expressed genes underlying aggressive behavior and also co-localize with binding sites of transcription factors involved in neuroplasticity or neurodevelopment. CONCLUSIONS There were DNA methylation differences in the brain associated with response to an intruder. These differences increased in number a few hours after the initial exposure and overlap with previously reported aggression-associated genes and neurobiologically relevant transcription factor binding sites. Many DNA methylation differences that occurred in association with the expression of aggression in real time also exist between Africanized bees and European bees, suggesting an evolutionarily conserved role for epigenetic regulation in aggressive behavior.
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Affiliation(s)
- Brian R Herb
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Molly S Shook
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Christopher J Fields
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Gene E Robinson
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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204
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Genome-Wide Characterization of DNA Methylation in an Invasive Lepidopteran Pest, the Cotton Bollworm Helicoverpa armigera. G3-GENES GENOMES GENETICS 2018; 8:779-787. [PMID: 29298815 PMCID: PMC5844299 DOI: 10.1534/g3.117.1112] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The genes and genomes of insect pests are shaped by the wide array of selective forces encountered in their environments. While the molecular adaptations that evolve are beginning to be understood at the genomic and transcriptomic level, they have been less well characterized at an epigenetic level. Here, we present a genome-wide map of DNA methylation at single-nucleotide resolution for the cotton bollworm moth, Helicoverpa armigera, a globally invasive pest of agriculture. We show that methylation is almost identical in the larvae and adults of H. armigera and that, through whole-genome bisulfite sequencing (WGBS), at the most ∼0.9% of CpG sites in this species are methylated. We find that DNA methylation occurs primarily in exons, is positively correlated with gene expression, and that methylated genes are enriched for cellular "housekeeping" roles. H. armigera has an exceptional capacity for long-range migration. To explore the role of methylation in influencing the migratory phenotype of H. armigera, we performed targeted bisulfite sequencing on selected loci from 16 genes that were differentially expressed between adult moths exhibiting distinct flight performance in behavioral assays. While most CpG sites in these genes were not methylated between flight phenotypes, we identified hypermethylation in a demethylase (KDM4) that targets lysine-specific histone modifications, which are strongly associated with transcription and methylation. The H. armigera methylome provides new insights into the role of DNA methylation in a noctuid moth and is a valuable resource for further research into the epigenetic control of adaptive traits in this important pest.
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205
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De Santis M, Locati M, Selmi C. The elegance of a macrophage. Cell Mol Immunol 2018; 15:196-198. [PMID: 28757608 PMCID: PMC5843624 DOI: 10.1038/cmi.2017.64] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 01/05/2023] Open
Affiliation(s)
- Maria De Santis
- Rheumatology and Clinical Immunology, Humanitas Research Hospital, Rozzano, Italy
| | - Massimo Locati
- Rheumatology and Clinical Immunology, Humanitas Research Hospital, Rozzano, Italy
- Laboratory of Leukocyte Biology, Humanitas Research Hospital, Rozzano, Italy
| | - Carlo Selmi
- Rheumatology and Clinical Immunology, Humanitas Research Hospital, Rozzano, Italy
- BIOMETRA Department, University of Milan, Milan, Italy
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206
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Nishikawa K, Kinjo AR. Mechanism of evolution by genetic assimilation : Equivalence and independence of genetic mutation and epigenetic modulation in phenotypic expression. Biophys Rev 2018; 10:667-676. [PMID: 29468522 DOI: 10.1007/s12551-018-0403-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 02/05/2018] [Indexed: 12/21/2022] Open
Abstract
Conrad H. Waddington discovered the phenomenon of genetic assimilation through a series of experiments on fruit flies. In those experiments, artificially exerted environmental stress induced plastic phenotypic changes in the fruit flies, but after some generations, the same phenotypic variant started to appear without the environmental stress. Both the initial state (where the phenotypic changes were environmentally induced and plastic) and the final state (where the phenotypic changes were genetically fixed and constitutive) are experimental facts. However, it remains unclear how the environmentally induced phenotypic change in the first generation becomes genetically fixed in the central process of genetic assimilation itself. We have argued that the key to understanding the mechanism of genetic assimilation lies in epigenetics, and proposed the "cooperative model" in which the evolutionary process depends on both genetic and epigenetic factors. Evolutionary simulations based on the cooperative model reproduced the process of genetic assimilation. Detailed analysis of the trajectories has revealed genetic assimilation is a process in which epigenetically induced phenotypic changes are incrementally and statistically replaced with multiple minor genetic mutations through natural selection. In this scenario, epigenetic and genetic changes may be considered as mutually independent but equivalent in terms of their effects on phenotypic changes. This finding rejects the common (and confused) hypothesis that epigenetically induced phenotypic changes depend on genetic mutations. Furthermore, we argue that transgenerational epigenetic inheritance is not required for evolution by genetic assimilation.
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Affiliation(s)
- Ken Nishikawa
- National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Akira R Kinjo
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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207
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Aging and nutrition induce tissue-specific changes on global DNA methylation status in rats. Mech Ageing Dev 2018; 174:47-54. [PMID: 29427568 DOI: 10.1016/j.mad.2018.02.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 01/31/2018] [Accepted: 02/06/2018] [Indexed: 01/12/2023]
Abstract
A number of epigenetic studies have demonstrated that DNA methylation patterns exhibit a tissue specificity, but not much has been done to highlight the extent of this phenomenon. Moreover, it is unknown how external factors modulate the plasticity of the tissue specific epigenetic profile. We examined global DNA methylation profiles in tissues from rats of different age, fed with standard or low-calorie diet, and evaluated their association with aging and nutrition. Tissue-specific variations occur during aging with hyper-methylation taking place in all tissues except for liver. The expression of enzymes involved in methylation reactions (DNMTs and TETs) was consistent with the methylation patterns. Nutrition affects global DNA methylation status throughout lifespan. Interestingly, the differences among different tissues are magnified in 96 weeks old rats fed with low calorie diet. Moreover, the low-calorie diet appears to affect the offspring's epigenetic status more strongly if administered during the maternal pre-gestational period than the gestational and lactation time. Therefore, we propose that changes in the global DNA methylation status may represent an epigenetic mechanism by which age and nutrition intersect each other and, in turn, influence the aging plasticity.
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208
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Li B, Hou L, Zhu D, Xu X, An S, Wang X. Identification and caste-dependent expression patterns of DNA methylation associated genes in Bombus terrestris. Sci Rep 2018; 8:2332. [PMID: 29402971 PMCID: PMC5799256 DOI: 10.1038/s41598-018-20831-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 01/24/2018] [Indexed: 11/09/2022] Open
Abstract
DNA methylation has been proposed to play critical roles in caste fate and behavioral plasticity in bumblebees, however, there is little information on its regulatory mechanisms. Here, we identified six important genes mediating the modification of DNA methylation and determined their expression patterns in the bumblebee Bombus terrestris. There is a complete functional DNA methylation system, including four DNA methyltransferases (DNMT1a, DNMT1b, DNMT2, and DNMT3), a DNA demethylase (Ten-eleven translocation), and a methyl-CpG-binding domain protein in B. terrestris. Most of these genes were highly expressed in fat bodies and gonads but lowly expressed in antennae and brains of bumblebee adults. Besides, these genes exhibited caste-specific expression patterns in bumblebees, with higher transcription levels in queens than workers and drones. Whereas their expression levels showed no remarkable difference in queenright and queenless workers. These results suggested potential roles of DNA methylation-related genes in caste differentiation in bumblebees.
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Affiliation(s)
- Beibei Li
- College of Plant Protection, Henan Agricultural University, Zhengzhou, 450002, China
| | - Li Hou
- Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Dan Zhu
- Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xilian Xu
- Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China
| | - Shiheng An
- College of Plant Protection, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Xianhui Wang
- Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
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209
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Kay S, Skowronski D, Hunt BG. Developmental DNA methyltransferase expression in the fire ant Solenopsis invicta. INSECT SCIENCE 2018; 25:57-65. [PMID: 27774769 DOI: 10.1111/1744-7917.12413] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/01/2016] [Accepted: 09/24/2016] [Indexed: 06/06/2023]
Abstract
DNA methylation is accomplished in animals by 2 classes of enzymes known as DNA methyltransferases, DNMT3 and DNMT1, which perform de novo methylation and maintenance methylation, respectively. Several studies of hymenopteran eusocial insects suggest that DNA methylation is capable of influencing developmental plasticity. However, fundamental questions remain about the patterning of DNA methylation during the course of insect development. In this study, we performed quantitative real-time PCR (qPCR) on transcripts from the single-copy orthologs of DNMT1 and DNMT3 in the red imported fire ant, Solenopsis invicta. In particular, we assessed the expression of S. invicta Dnmt1 and Dnmt3 mRNA during 7 stages of worker development, among behaviorally distinct adults, and among male and female gonads. Dnmt3 was most highly expressed during embryonic development, whereas Dnmt1 was similarly expressed throughout the course of development. Moreover, Dnmt1 and Dnmt3 were highly expressed in testes and ovaries. Neither Dnmt was significantly differentially expressed among heads of behaviorally distinct adult castes. Our results support the hypothesis that extensive patterning of DNA methylation occurs during gametogenesis and embryogenesis in the insect order Hymenoptera.
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Affiliation(s)
- Sasha Kay
- Department of Entomology, University of Georgia, Griffin, Georgia, USA
| | - Daniel Skowronski
- Department of Entomology, University of Georgia, Griffin, Georgia, USA
| | - Brendan G Hunt
- Department of Entomology, University of Georgia, Griffin, Georgia, USA
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210
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Nijhout HF, McKenna KZ. The distinct roles of insulin signaling in polyphenic development. CURRENT OPINION IN INSECT SCIENCE 2018; 25:58-64. [PMID: 29602363 DOI: 10.1016/j.cois.2017.11.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/05/2017] [Accepted: 11/21/2017] [Indexed: 06/08/2023]
Abstract
Many insects have the ability to develop alternative morphologies in response to specific environmental signals such as photoperiod, temperature, nutrition and crowding. These signals are integrated by the brain and result in alternative patterns of secretion of developmental hormones like ecdysone, juvenile hormone and insulin-like growth factors, which, in turn, direct alternative developmental trajectories. Insulin signaling appears to be particularly important when the polyphenism involves differences in the sizes of the body, appendages and other structures, such as wings, mandibles and horns. Here we review recent advances in understanding the role of insulin signaling, and its interaction with other hormones, in the development of polyphenisms.
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211
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Beyond Royalactin and a master inducer explanation of phenotypic plasticity in honey bees. Commun Biol 2018; 1:8. [PMID: 30271895 PMCID: PMC6123742 DOI: 10.1038/s42003-017-0004-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 11/06/2017] [Indexed: 12/26/2022] Open
Abstract
Distinct female castes produced from one genotype are the trademark of a successful evolutionary invention in eusocial insects known as reproductive division of labour. In honey bees, fertile queens develop from larvae fed a complex diet called royal jelly. Recently, one protein in royal jelly, dubbed Royalactin, was deemed to be the exclusive driver of queen bee determination. However, this notion has not been universally accepted. Here I critically evaluate this line of research and argue that the sheer complexity of creating alternate phenotypes from one genotype cannot be reduced to a single dietary component. An acceptable model of environmentally driven caste differentiation should include the facets of dynamic thinking, such as the concepts of attractor states and genetic hierarchical networks. In honeybees, genotypically identical females develop into queens or sterile workers, depending on their diets. In this review, Ryszard Maleszka discusses the controversial role of the royal jelly protein Royalactin in caste determination and provides a framework for moving beyond the master inducer concept.
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212
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Pennell TM, Holman L, Morrow EH, Field J. Building a new research framework for social evolution: intralocus caste antagonism. Biol Rev Camb Philos Soc 2018; 93:1251-1268. [PMID: 29341390 PMCID: PMC5896731 DOI: 10.1111/brv.12394] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 12/06/2017] [Accepted: 12/18/2017] [Indexed: 01/02/2023]
Abstract
The breeding and non‐breeding ‘castes’ of eusocial insects provide a striking example of role‐specific selection, where each caste maximises fitness through different morphological, behavioural and physiological trait values. Typically, queens are long‐lived egg‐layers, while workers are short‐lived, largely sterile foragers. Remarkably, the two castes are nevertheless produced by the same genome. The existence of inter‐caste genetic correlations is a neglected consequence of this shared genome, potentially hindering the evolution of caste dimorphism: alleles that increase the productivity of queens may decrease the productivity of workers and vice versa, such that each caste is prevented from reaching optimal trait values. A likely consequence of this ‘intralocus caste antagonism’ should be the maintenance of genetic variation for fitness and maladaptation within castes (termed ‘caste load’), analogous to the result of intralocus sexual antagonism. The aim of this review is to create a research framework for understanding caste antagonism, drawing in part upon conceptual similarities with sexual antagonism. By reviewing both the social insect and sexual antagonism literature, we highlight the current empirical evidence for caste antagonism, discuss social systems of interest, how antagonism might be resolved, and challenges for future research. We also introduce the idea that sexual and caste antagonism could interact, creating a three‐way antagonism over gene expression. This includes unpacking the implications of haplodiploidy for the outcome of this complex interaction.
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Affiliation(s)
- Tanya M Pennell
- College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
| | - Luke Holman
- School of Biosciences, University of Melbourne, Parkville, Victoria, 3052, Australia
| | - Edward H Morrow
- Evolution Behaviour and Environment Group, School of Life Sciences, University of Sussex, Falmer, East Sussex, BN1 9QG, UK
| | - Jeremy Field
- College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
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213
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Abstract
The genome revolution represents a complete change on our view of biological systems. The quantitative determination of changes in all major molecular components of the living cells, the "omics" approach, opened whole new fields for all health sciences. Genomics, transcriptomics, proteomics, metabolomics, and others, together with appropriate prediction and modeling tools, will mark the future of developmental toxicity assessment both for wildlife and humans. This is especially true for disciplines, like teratology, which rely on studies in model organisms, as studies at lower levels of organization are difficult to implement. Rodents and frogs have been the favorite models for studying human reproductive and developmental disorders for decades. Recently, the study of the development of zebrafish embryos (ZE) is becoming a major alternative tool to adult animal testing. ZE intrinsic characteristics makes this model a unique system to analyze in vivo developmental alterations that only can be studied applying in toto approaches. Moreover, under actual legislations, ZE is considered as a replacement model (and therefore, excluded from animal welfare regulations) during the first 5 days after fertilization. Here we review the most important components of the zebrafish toolbox available for analyzing early stages of embryotoxic events that could eventually lead to teratogenesis.
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214
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Insulin-like peptides and DNA/tRNA methyltransferases are involved in the nutritional regulation of female reproduction in Nilaparvata lugens (Stål). Gene 2018; 639:96-105. [DOI: 10.1016/j.gene.2017.10.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 10/05/2017] [Accepted: 10/06/2017] [Indexed: 11/22/2022]
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215
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van Dongen J, Bonder MJ, Dekkers KF, Nivard MG, van Iterson M, Willemsen G, Beekman M, van der Spek A, van Meurs JBJ, Franke L, Heijmans BT, van Duijn CM, Slagboom PE, Boomsma DI. DNA methylation signatures of educational attainment. NPJ SCIENCE OF LEARNING 2018; 3:7. [PMID: 30631468 PMCID: PMC6220239 DOI: 10.1038/s41539-018-0020-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/18/2017] [Accepted: 02/09/2018] [Indexed: 05/09/2023]
Abstract
Educational attainment is a key behavioural measure in studies of cognitive and physical health, and socioeconomic status. We measured DNA methylation at 410,746 CpGs (N = 4152) and identified 58 CpGs associated with educational attainment at loci characterized by pleiotropic functions shared with neuronal, immune and developmental processes. Associations overlapped with those for smoking behaviour, but remained after accounting for smoking at many CpGs: Effect sizes were on average 28% smaller and genome-wide significant at 11 CpGs after adjusting for smoking and were 62% smaller in never smokers. We examined sources and biological implications of education-related methylation differences, demonstrating correlations with maternal prenatal folate, smoking and air pollution signatures, and associations with gene expression in cis, dynamic methylation in foetal brain, and correlations between blood and brain. Our findings show that the methylome of lower-educated people resembles that of smokers beyond effects of their own smoking behaviour and shows traces of various other exposures.
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Affiliation(s)
- Jenny van Dongen
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Marc Jan Bonder
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Koen F. Dekkers
- Molecular Epidemiology section, Leiden University Medical Center, Leiden, The Netherlands
| | - Michel G. Nivard
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Maarten van Iterson
- Molecular Epidemiology section, Leiden University Medical Center, Leiden, The Netherlands
| | - Gonneke Willemsen
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Marian Beekman
- Molecular Epidemiology section, Leiden University Medical Center, Leiden, The Netherlands
| | - Ashley van der Spek
- Department of Epidemiology, Genetic Epidemiology Unit, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Lude Franke
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Bastiaan T. Heijmans
- Molecular Epidemiology section, Leiden University Medical Center, Leiden, The Netherlands
| | - Cornelia M. van Duijn
- Department of Epidemiology, Genetic Epidemiology Unit, Erasmus Medical Center, Rotterdam, The Netherlands
| | - P. Eline Slagboom
- Molecular Epidemiology section, Leiden University Medical Center, Leiden, The Netherlands
| | - Dorret I. Boomsma
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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216
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Cardoso-Júnior CAM, Guidugli-Lazzarini KR, Hartfelder K. DNA methylation affects the lifespan of honey bee (Apis mellifera L.) workers - Evidence for a regulatory module that involves vitellogenin expression but is independent of juvenile hormone function. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 92:21-29. [PMID: 29157677 DOI: 10.1016/j.ibmb.2017.11.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 11/06/2017] [Accepted: 11/09/2017] [Indexed: 06/07/2023]
Abstract
The canonic regulatory module for lifespan of honey bee (Apis mellifera) workers involves a mutual repressor relationship between juvenile hormone (JH) and vitellogenin (Vg). Compared to vertebrates, however, little is known about a possible role of epigenetic factors. The full genomic repertoire of DNA methyltransferases (DNMTs) makes the honey bee an attractive emergent model for studying the role of epigenetics in the aging process of invertebrates, and especially so in social insects. We first quantified the transcript levels of the four DNMTs encoding genes in the head thorax and abdomens of workers of different age, showing that dnmt1a and dnmt3 expression is up-regulated in abdomens of old workers, whereas dnmt1b and dnmt2 are down-regulated in heads of old workers. Pharmacological genome demethylation by RG108 treatment caused an increase in worker lifespan. Next, we showed that the genomic DNA methylation status indirectly affects vitellogenin gene expression both in vitro and in vivo in young workers, and that this occurs independent of caloric restriction or JH levels, suggesting that a non-canonical circuitry may be acting in parallel with the JH/Vg module to regulate the adult life cycle of honey bee workers. Our data provide evidence that epigenetic factors play a role in regulatory networks associated with complex life history traits of a social insect.
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Affiliation(s)
- Carlos A M Cardoso-Júnior
- Departamento de Biologia Celular, Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14049-900, Brazil.
| | - Karina R Guidugli-Lazzarini
- Departamento de Biologia Celular, Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14049-900, Brazil.
| | - Klaus Hartfelder
- Departamento de Biologia Celular, Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14049-900, Brazil.
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Genome-wide DNA methylation changes associated with olfactory learning and memory in Apis mellifera. Sci Rep 2017; 7:17017. [PMID: 29208987 PMCID: PMC5717273 DOI: 10.1038/s41598-017-17046-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 11/08/2017] [Indexed: 12/25/2022] Open
Abstract
The honeybee is a model organism for studying learning and memory formation and its underlying molecular mechanisms. While DNA methylation is well studied in caste differentiation, its role in learning and memory is not clear in honeybees. Here, we analyzed genome-wide DNA methylation changes during olfactory learning and memory process in A. mellifera using whole genome bisulfite sequencing (WGBS) method. A total of 853 significantly differentially methylated regions (DMRs) and 963 differentially methylated genes (DMGs) were identified. We discovered that 440 DMRs of 648 genes were hypermethylated and 274 DMRs of 336 genes were hypomethylated in trained group compared to untrained group. Of these DMGs, many are critical genes involved in learning and memory, such as Creb, GABABR and Ip3k, indicating extensive involvement of DNA methylation in honeybee olfactory learning and memory process. Furthermore, key enzymes for histone methylation, RNA editing and miRNA processing also showed methylation changes during this process, implying that DNA methylation can affect learning and memory of honeybees by regulating other epigenetic modification processes.
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218
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Mitochondrial mothers of a fat nation: Race, gender and epigenetics in obesity research on Mexican mestizos. BIOSOCIETIES 2017. [DOI: 10.1057/s41292-017-0078-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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219
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Tubbs CW, McDonough CE. Reproductive Impacts of Endocrine-Disrupting Chemicals on Wildlife Species: Implications for Conservation of Endangered Species. Annu Rev Anim Biosci 2017; 6:287-304. [PMID: 29140722 DOI: 10.1146/annurev-animal-030117-014547] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Wildlife have proven valuable to our understanding of the potential effects of endocrine-disrupting chemicals (EDCs) on human health by contributing considerably to our understanding of the mechanisms and consequences of EDC exposure. But the threats EDCs present to populations of wildlife species themselves are significant, particularly for endangered species whose existence is vulnerable to any reproductive perturbation. However, few studies address the threats EDCs pose to endangered species owing to challenges associated with their study. Here, we highlight those barriers and review the available literature concerning EDC effects on endangered species. Drawing from other investigations into nonthreatened wildlife species, we highlight opportunities for new approaches to advance our understanding and potentially mitigate the effects of EDCs on endangered species to enhance their fertility.
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Affiliation(s)
- Christopher W Tubbs
- San Diego Zoo Global, Institute for Conservation Research, Escondido, California 92027, USA;
| | - Caitlin E McDonough
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, New York 13244, USA;
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220
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Linz DM, Moczek AP. Homology is dead! Long live homology! A review of Deep Homology? Evol Dev 2017. [DOI: 10.1111/ede.12241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David M. Linz
- Department of Biology; Indiana University; Bloomington Indiana USA
| | - Armin P. Moczek
- Department of Biology; Indiana University; Bloomington Indiana USA
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Steijven K, Spaethe J, Steffan-Dewenter I, Härtel S. Learning performance and brain structure of artificially-reared honey bees fed with different quantities of food. PeerJ 2017; 5:e3858. [PMID: 29085743 PMCID: PMC5657415 DOI: 10.7717/peerj.3858] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 09/06/2017] [Indexed: 11/24/2022] Open
Abstract
Background Artificial rearing of honey bee larvae is an established method which enables to fully standardize the rearing environment and to manipulate the supplied diet to the brood. However, there are no studies which compare learning performance or neuroanatomic differences of artificially-reared (in-lab) bees in comparison with their in-hive reared counterparts. Methods Here we tested how different quantities of food during larval development affect body size, brain morphology and learning ability of adult honey bees. We used in-lab rearing to be able to manipulate the total quantity of food consumed during larval development. After hatching, a subset of the bees was taken for which we made 3D reconstructions of the brains using confocal laser-scanning microscopy. Learning ability and memory formation of the remaining bees was tested in a differential olfactory conditioning experiment. Finally, we evaluated how bees reared with different quantities of artificial diet compared to in-hive reared bees. Results Thorax and head size of in-lab reared honey bees, when fed the standard diet of 160 µl or less, were slightly smaller than hive bees. The brain structure analyses showed that artificially reared bees had smaller mushroom body (MB) lateral calyces than their in-hive counterparts, independently of the quantity of food they received. However, they showed the same total brain size and the same associative learning ability as in-hive reared bees. In terms of mid-term memory, but not early long-term memory, they performed even better than the in-hive control. Discussion We have demonstrated that bees that are reared artificially (according to the Aupinel protocol) and kept in lab-conditions perform the same or even better than their in-hive sisters in an olfactory conditioning experiment even though their lateral calyces were consistently smaller at emergence. The applied combination of experimental manipulation during the larval phase plus subsequent behavioral and neuro-anatomic analyses is a powerful tool for basic and applied honey bee research.
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Affiliation(s)
- Karin Steijven
- Department of Animal Ecology & Tropical Biology, University of Würzburg, Würzburg, Germany.,Lectorat Bee Health-Domain Animals and Business, Van Hall Larenstein, University of Applied Sciences, Leeuwarden, Netherlands
| | - Johannes Spaethe
- Department of Behavioral Physiology & Sociobiology, University of Würzburg, Würzburg, Germany
| | | | - Stephan Härtel
- Department of Animal Ecology & Tropical Biology, University of Würzburg, Würzburg, Germany
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223
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Lyko F. The DNA methyltransferase family: a versatile toolkit for epigenetic regulation. Nat Rev Genet 2017; 19:81-92. [PMID: 29033456 DOI: 10.1038/nrg.2017.80] [Citation(s) in RCA: 795] [Impact Index Per Article: 113.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The DNA methyltransferase (DNMT) family comprises a conserved set of DNA-modifying enzymes that have a central role in epigenetic gene regulation. Recent studies have shown that the functions of the canonical DNMT enzymes - DNMT1, DNMT3A and DNMT3B - go beyond their traditional roles of establishing and maintaining DNA methylation patterns. This Review analyses how molecular interactions and changes in gene copy numbers modulate the activity of DNMTs in diverse gene regulatory functions, including transcriptional silencing, transcriptional activation and post-transcriptional regulation by DNMT2-dependent tRNA methylation. This mechanistic diversity enables the DNMT family to function as a versatile toolkit for epigenetic regulation.
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Affiliation(s)
- Frank Lyko
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
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224
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Kanada K, Takeshita K, Suetake I, Tajima S, Nakagawa A. Conserved threonine 1505 in the catalytic domain stabilizes mouse DNA methyltransferase 1. J Biochem 2017; 162:271-278. [PMID: 28369487 DOI: 10.1093/jb/mvx024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/15/2017] [Indexed: 11/14/2022] Open
Abstract
In mammals, DNA methyltransferase 1 (DNMT1) is responsible for propagating the DNA methylation pattern into the next generation through selective methylation of hemi-methylated CpG that emerges just after replication, a process known as maintenance methylation. The T1505, which is conserved among DNMT1s of vertebrates, in the catalytic domain of mouse DNMT1 forms the hydrogen bond with the W1512, which is also conserved among vertebrates and one of the essential residues in recognition of the 5-methylcytosine in hemi-methylated CpGs. However, importance of the hydrogen bond between T1505 and W1512 is unknown. In this study, we determined the crystal structure of mouse DNMT1(291-1620) that replaced T1505 with alanine (DNMT1(291-1620)T1505A) and examined its DNA methylation activity in vitro. Although the mutation lost the hydrogen bond between T1505 and W1512, the overall structure of DNMT1(291-1620)T1505A remained almost identical with that of the wild type. Structural stability and DNA methylation activity of DNMT1(291-1620)T1505A under physiological temperature were lower than those of DNMT1(291-1620). T1505 is crucial on the DNA methylation activity of DNMT1 through stabilizing its structure during ongoing round of DNA methylation.
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Affiliation(s)
- Kensaku Kanada
- The Laboratory of Supramolecular Crystallography, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kohei Takeshita
- The Laboratory of Supramolecular Crystallography, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Isao Suetake
- The Laboratory of Epigenetics, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shoji Tajima
- The Laboratory of Epigenetics, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Atsushi Nakagawa
- The Laboratory of Supramolecular Crystallography, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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225
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Velando A, Costa MM, Kim SY. Sex-specific phenotypes and metabolism-related gene expression in juvenile sticklebacks. Behav Ecol 2017. [DOI: 10.1093/beheco/arx129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Affiliation(s)
- Alberto Velando
- Departamento de Ecoloxía e Bioloxía Animal, Campus As Lagoas, Universidade de Vigo, 36310 Vigo, Spain
| | - María M Costa
- Departamento de Ecoloxía e Bioloxía Animal, Campus As Lagoas, Universidade de Vigo, 36310 Vigo, Spain
| | - Sin-Yeon Kim
- Departamento de Ecoloxía e Bioloxía Animal, Campus As Lagoas, Universidade de Vigo, 36310 Vigo, Spain
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226
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Kusari F, O'Doherty AM, Hodges NJ, Wojewodzic MW. Bi-directional effects of vitamin B 12 and methotrexate on Daphnia magna fitness and genomic methylation. Sci Rep 2017; 7:11872. [PMID: 28928387 PMCID: PMC5605502 DOI: 10.1038/s41598-017-12148-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 09/04/2017] [Indexed: 12/19/2022] Open
Abstract
Here we interrogated, using three separate but complementary experimental approaches, the impact of vitamin B12 availability and methotrexate exposure on Daphnia magna, which we hypothesised should have an opposite effect on One carbon metabolism (OCM). OCM is a vital biological process supporting a variety of physiological processes, including DNA methylation. Contrary to mammalian models, this process remains largely unexplored in invertebrates. The purpose of this study was to elucidate the impact of OCM short-term alteration on the fitness and epigenome of the keystone species, Daphnia. We used maternal age at reproduction, brood size and survival rates in combination with DNA methylation sensitive comet assay to determine the effects of vitamin B12 or MTX on fitness and the epigenome. Vitamin B12 had a positive influence on Daphnia fitness and we provide evidence demonstrating that this may be associated with an increased level of genome-wide DNA methylation. Conversely, exposing D. magna to MTX negatively influenced the fitness of the animals and was associated with loss of global DNA methylation, translating in decreased fitness. These results highlight the potential importance of OCM in invertebrates, providing novel evidence supporting a potential role for epigenetic modifications to the genome in D. magna environmental adaptability.
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Affiliation(s)
- Fitore Kusari
- University of Birmingham, School of Biosciences, Edgbaston, Birmingham, B15 2TT,, UK
| | - Alan M O'Doherty
- School of Agriculture & Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Nikolas J Hodges
- University of Birmingham, School of Biosciences, Edgbaston, Birmingham, B15 2TT,, UK
| | - Marcin W Wojewodzic
- University of Birmingham, School of Biosciences, Edgbaston, Birmingham, B15 2TT,, UK.
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227
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Riyahi S, Vilatersana R, Schrey AW, Ghorbani Node H, Aliabadian M, Senar JC. Natural epigenetic variation within and among six subspecies of the house sparrow, Passer domesticus. ACTA ACUST UNITED AC 2017; 220:4016-4023. [PMID: 28877923 DOI: 10.1242/jeb.169268] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/01/2017] [Indexed: 12/30/2022]
Abstract
Epigenetic modifications can respond rapidly to environmental changes and can shape phenotypic variation in accordance with environmental stimuli. One of the most studied epigenetic marks is DNA methylation. In the present study, we used the methylation-sensitive amplified polymorphism (MSAP) technique to investigate the natural variation in DNA methylation within and among subspecies of the house sparrow, Passer domesticus We focused on five subspecies from the Middle East because they show great variation in many ecological traits and because this region is the probable origin for the house sparrow's commensal relationship with humans. We analysed house sparrows from Spain as an outgroup. The level of variation in DNA methylation was similar among the five house sparrow subspecies from the Middle East despite high phenotypic and environmental variation, but the non-commensal subspecies was differentiated from the other four (commensal) Middle Eastern subspecies. Further, the European subspecies was differentiated from all other subspecies in DNA methylation. Our results indicate that variation in DNA methylation does not strictly follow subspecies designations. We detected a correlation between methylation level and some morphological traits, such as standardized bill length, and we suggest that part of the high morphological variation in the native populations of the house sparrow is influenced by differentially methylated regions in specific loci throughout the genome. We also detected 10 differentially methylated loci among subspecies and three loci that differentiated between commensal or non-commensal status. Therefore, the MSAP technique detected larger scale differences among the European and non-commensal subspecies, but did not detect finer scale differences among the other Middle Eastern subspecies.
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Affiliation(s)
- Sepand Riyahi
- Evolutionary and Behavioural Ecology Research Unit, Natural History Museum of Barcelona, Psg. Picasso s/n, 08003 Barcelona, Spain
| | - Roser Vilatersana
- Botanic Institute of Barcelona (IBB-CSIC-ICUB), Passeig de Migdia s/n, 08038 Barcelona, Spain
| | - Aaron W Schrey
- Department of Biology, Armstrong State University, Savannah, GA 31419, USA
| | - Hassan Ghorbani Node
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad 9177 9489 74, Iran.,Research Department of Zoological Innovations, Institute of Applied Zoology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad 9177 9489 74, Iran
| | - Mansour Aliabadian
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad 9177 9489 74, Iran.,Research Department of Zoological Innovations, Institute of Applied Zoology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad 9177 9489 74, Iran
| | - Juan Carlos Senar
- Evolutionary and Behavioural Ecology Research Unit, Natural History Museum of Barcelona, Psg. Picasso s/n, 08003 Barcelona, Spain
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228
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Sex-specific inhibition and stimulation of worker-reproductive transition in a termite. Naturwissenschaften 2017; 104:79. [PMID: 28879477 DOI: 10.1007/s00114-017-1501-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/28/2017] [Accepted: 08/30/2017] [Indexed: 10/18/2022]
Abstract
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.
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229
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Zhu K, Liu M, Fu Z, Zhou Z, Kong Y, Liang H, Lin Z, Luo J, Zheng H, Wan P, Zhang J, Zen K, Chen J, Hu F, Zhang CY, Ren J, Chen X. Plant microRNAs in larval food regulate honeybee caste development. PLoS Genet 2017; 13:e1006946. [PMID: 28859085 PMCID: PMC5578494 DOI: 10.1371/journal.pgen.1006946] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 07/27/2017] [Indexed: 11/18/2022] Open
Abstract
The major environmental determinants of honeybee caste development come from larval nutrients: royal jelly stimulates the differentiation of larvae into queens, whereas beebread leads to worker bee fate. However, these determinants are not fully characterized. Here we report that plant RNAs, particularly miRNAs, which are more enriched in beebread than in royal jelly, delay development and decrease body and ovary size in honeybees, thereby preventing larval differentiation into queens and inducing development into worker bees. Mechanistic studies reveal that amTOR, a stimulatory gene in caste differentiation, is the direct target of miR162a. Interestingly, the same effect also exists in non-social Drosophila. When such plant RNAs and miRNAs are fed to Drosophila larvae, they cause extended developmental times and reductions in body weight and length, ovary size and fecundity. This study identifies an uncharacterized function of plant miRNAs that fine-tunes honeybee caste development, offering hints for understanding cross-kingdom interaction and co-evolution. How caste has formed in honeybees is an enduring puzzle. The prevailing view is that royal jelly stimulates the differentiation of larvae into queen. Here, we uncover a new mechanism that plant miRNAs in worker bee’s food postpone larval development, thereby inducing sterile worker bees. Thus, the theories about honeybee caste formation need to be re-examined from a new angle besides the traditional focus on royal jelly and its components. Furthermore, since miRNAs are transmitted between species of different kingdoms and can contribute to the phenotype regulation, this new model of horizontal miRNA transfer may open up a new avenue to further study the molecular mechanisms underlying cross-kingdom interaction and co-evolution.
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Affiliation(s)
- Kegan Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Minghui Liu
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Zheng Fu
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Zhen Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Yan Kong
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Hongwei Liang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Zheguang Lin
- College of Animal Science, Zhejiang University, Hangzhou, China
| | - Jun Luo
- Model Animal Research Center and MOE Key Laboratory of Model Animals for Disease Study, Nanjing University, Nanjing, China
| | - Huoqing Zheng
- College of Animal Science, Zhejiang University, Hangzhou, China
| | - Ping Wan
- Model Animal Research Center and MOE Key Laboratory of Model Animals for Disease Study, Nanjing University, Nanjing, China
| | - Junfeng Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Ke Zen
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
| | - Jiong Chen
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
- Model Animal Research Center and MOE Key Laboratory of Model Animals for Disease Study, Nanjing University, Nanjing, China
- * E-mail: (XC); (JR); (CZ); (FH); (JC)
| | - Fuliang Hu
- College of Animal Science, Zhejiang University, Hangzhou, China
- * E-mail: (XC); (JR); (CZ); (FH); (JC)
| | - Chen-Yu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
- * E-mail: (XC); (JR); (CZ); (FH); (JC)
| | - Jie Ren
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States of America
- * E-mail: (XC); (JR); (CZ); (FH); (JC)
| | - Xi Chen
- State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University, Nanjing, China
- * E-mail: (XC); (JR); (CZ); (FH); (JC)
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Abstract
The study of insect social behavior has offered tremendous insight into the molecular mechanisms mediating behavioral and phenotypic plasticity. Genomic applications to the study of eusocial insect species, in particular, have led to several hypotheses for the processes underlying the molecular evolution of behavior. Advances in understanding the genetic control of social organization have also been made, suggesting an important role for supergenes in the evolution of divergent behavioral phenotypes. Intensive study of social phenotypes across species has revealed that behavior and caste are controlled by an interaction between genetic and environmentally mediated effects and, further, that gene expression and regulation mediate plastic responses to environmental signals. However, several key methodological flaws that are hindering progress in the study of insect social behavior remain. After reviewing the current state of knowledge, we outline ongoing challenges in experimental design that remain to be overcome in order to advance the field.
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Affiliation(s)
- Chelsea A Weitekamp
- Department of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland; ,
| | - Romain Libbrecht
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, 55128 Mainz, Germany;
| | - Laurent Keller
- Department of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland; ,
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231
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Genome-wide DNA methylation and transcriptome analyses reveal genes involved in immune responses of pig peripheral blood mononuclear cells to poly I:C. Sci Rep 2017; 7:9709. [PMID: 28852164 PMCID: PMC5575306 DOI: 10.1038/s41598-017-10648-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 08/10/2017] [Indexed: 12/14/2022] Open
Abstract
DNA methylation changes play essential roles in regulating the activities of genes involved in immune responses. Understanding of variable DNA methylation linked to immune responses may contribute to identifying biologically promising epigenetic markers for pathogenesis of diseases. Here, we generated genome-wide DNA methylation and transcriptomic profiles of six pairs of polyinosinic-polycytidylic acid-treated pig peripheral blood mononuclear cell (PBMC) samples and corresponding controls using methylated DNA immunoprecipitation sequencing and RNA sequencing. Comparative methylome analyses identified 5,827 differentially methylated regions and 615 genes showing differential expression between the two groups. Integrative analyses revealed inverse associations between DNA methylation around transcriptional start site and gene expression levels. Furthermore, 70 differentially methylated and expressed genes were identified such as TNFRSF9, IDO1 and EBI3. Functional annotation revealed the enriched categories including positive regulation of immune system process and regulation of leukocyte activation. These findings demonstrated DNA methylation changes occurring in immune responses of PBMCs to poly I:C stimulation and a subset of genes potentially regulated by DNA methylation in the immune responses. The PBMC DNA methylome provides an epigenetic overview of this physiological system in response to viral infection, and we expect it to constitute a valuable resource for future epigenetic epidemiology studies in pigs.
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232
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Dimond JL, Gamblewood SK, Roberts SB. Genetic and epigenetic insight into morphospecies in a reef coral. Mol Ecol 2017; 26:5031-5042. [DOI: 10.1111/mec.14252] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 12/27/2022]
Affiliation(s)
- James L. Dimond
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
- Shannon Point Marine Center Western Washington University Anacortes WA USA
| | | | - Steven B. Roberts
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
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233
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Gibert JM. The flexible stem hypothesis: evidence from genetic data. Dev Genes Evol 2017; 227:297-307. [PMID: 28780641 DOI: 10.1007/s00427-017-0589-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 07/20/2017] [Indexed: 11/29/2022]
Abstract
Phenotypic plasticity, the ability of a given genotype to produce different phenotypes in response to distinct environmental conditions, is widely observed in the wild. It is believed to facilitate evolution and, under the "flexible stem hypothesis", it is thought that an ancestral plastic species can be at the origin of sister lineages with divergent phenotypes fixed by genetic assimilation of alternative morphs. We review here the genetic mechanisms underlying such phenomenon. We show several examples in which the same gene shows transcriptional plasticity in response to environmental factors and divergence of expression within or between species. Thus, the same gene is involved both in the plasticity of a trait and in the evolution of that trait. In a few cases, it can be traced down to cis-regulatory variation in this gene and, in one case, in the very same regulatory sequence whose activity is modulated by the environment. These data are compatible with the "flexible stem hypothesis" and also suggest that the evolution of the plasticity of a trait and the evolution of the trait are not completely uncoupled as they often involve the same locus. Furthermore, the "flexible stem hypothesis" implies that it is possible to canalize initially plastic phenotypes. Several studies have shown that it was possible through modification of chromatin regulation or hormonal signalling/response. Further studies of phenotypic plasticity in an evolutionary framework are needed to see how much the findings described in this review can be generalized.
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Affiliation(s)
- Jean-Michel Gibert
- Sorbonne Universités, UPMC Université Paris 06, CNRS, Biologie du Développement Paris Seine, Institut de Biologie Paris Seine (LBD-IBPS), 75005, Paris, France.
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Werner MS, Sieriebriennikov B, Loschko T, Namdeo S, Lenuzzi M, Dardiry M, Renahan T, Sharma DR, Sommer RJ. Environmental influence on Pristionchus pacificus mouth form through different culture methods. Sci Rep 2017; 7:7207. [PMID: 28775277 PMCID: PMC5543044 DOI: 10.1038/s41598-017-07455-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/28/2017] [Indexed: 12/29/2022] Open
Abstract
Environmental cues can impact development to elicit distinct phenotypes in the adult. The consequences of phenotypic plasticity can have profound effects on morphology, life cycle, and behavior to increase the fitness of the organism. The molecular mechanisms governing these interactions are beginning to be elucidated in a few cases, such as social insects. Nevertheless, there is a paucity of systems that are amenable to rigorous experimentation, preventing both detailed mechanistic insight and the establishment of a generalizable conceptual framework. The mouth dimorphism of the model nematode Pristionchus pacificus offers the rare opportunity to examine the genetics, genomics, and epigenetics of environmental influence on developmental plasticity. Yet there are currently no easily tunable environmental factors that affect mouth-form ratios and are scalable to large cultures required for molecular biology. Here we present a suite of culture conditions to toggle the mouth-form phenotype of P. pacificus. The effects are reversible, do not require the costly or labor-intensive synthesis of chemicals, and proceed through the same pathways previously examined from forward genetic screens. Different species of Pristionchus exhibit different responses to culture conditions, demonstrating unique gene-environment interactions, and providing an opportunity to study environmental influence on a macroevolutionary scale.
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Affiliation(s)
- Michael S Werner
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Bogdan Sieriebriennikov
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Tobias Loschko
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Suryesh Namdeo
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Masa Lenuzzi
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Mohannad Dardiry
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Tess Renahan
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Devansh Raj Sharma
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Ralf J Sommer
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany.
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235
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Hu J, Barrett RDH. Epigenetics in natural animal populations. J Evol Biol 2017; 30:1612-1632. [PMID: 28597938 DOI: 10.1111/jeb.13130] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 06/01/2017] [Accepted: 06/03/2017] [Indexed: 12/22/2022]
Abstract
Phenotypic plasticity is an important mechanism for populations to buffer themselves from environmental change. While it has long been appreciated that natural populations possess genetic variation in the extent of plasticity, a surge of recent evidence suggests that epigenetic variation could also play an important role in shaping phenotypic responses. Compared with genetic variation, epigenetic variation is more likely to have higher spontaneous rates of mutation and a more sensitive reaction to environmental inputs. In our review, we first provide an overview of recent studies on epigenetically encoded thermal plasticity in animals to illustrate environmentally-mediated epigenetic effects within and across generations. Second, we discuss the role of epigenetic effects during adaptation by exploring population epigenetics in natural animal populations. Finally, we evaluate the evolutionary potential of epigenetic variation depending on its autonomy from genetic variation and its transgenerational stability. Although many of the causal links between epigenetic variation and phenotypic plasticity remain elusive, new data has explored the role of epigenetic variation in facilitating evolution in natural populations. This recent progress in ecological epigenetics will be helpful for generating predictive models of the capacity of organisms to adapt to changing climates.
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Affiliation(s)
- J Hu
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
| | - R D H Barrett
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
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236
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Vieira GC, Vieira GF, Sinigaglia M, da Silva Valente VL. Linking epigenetic function to electrostatics: The DNMT2 structural model example. PLoS One 2017; 12:e0178643. [PMID: 28575027 PMCID: PMC5456315 DOI: 10.1371/journal.pone.0178643] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 05/16/2017] [Indexed: 11/25/2022] Open
Abstract
The amino acid sequence of DNMT2 is very similar to the catalytic domains of bacterial and eukaryotic proteins. However, there is great variability in the region of recognition of the target sequence. While bacterial DNMT2 acts as a DNA methyltransferase, previous studies have indicated low DNA methylation activity in eukaryotic DNMT2, with preference by tRNA methylation. Drosophilids are known as DNMT2-only species and the DNA methylation phenomenon is a not elucidated case yet, as well as the ontogenetic and physiologic importance of DNMT2 for this species group. In addition, more recently study showed that methylation in the genome in Drosophila melanogaster is independent in relation to DNMT2. Despite these findings, Drosophilidae family has more than 4,200 species with great ecological diversity and historical evolution, thus we, therefore, aimed to examine the drosophilids DNMT2 in order to verify its conservation at the physicochemical and structural levels in a functional context. We examined the twenty-six DNMT2 models generated by molecular modelling and five crystallographic structures deposited in the Protein Data Bank (PDB) using different approaches. Our results showed that despite sequence and structural similarity between species close related, we found outstanding differences when they are analyzed in the context of surface distribution of electrostatic properties. The differences found in the electrostatic potentials may be linked with different affinities and processivity of DNMT2 for its different substrates (DNA, RNA or tRNA) and even for interactions with other proteins involved in the epigenetic mechanisms.
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Affiliation(s)
- Gilberto Cavalheiro Vieira
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- * E-mail:
| | - Gustavo Fioravanti Vieira
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Núcleo de Bioinformática do Laboratório de Imunogenética, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Marialva Sinigaglia
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Instituto do Câncer Infantil, Porto Alegre, RS, Brazil
| | - Vera Lúcia da Silva Valente
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
- Programa de Pós Graduação em Biologia Animal, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
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237
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de Luca A, Hankard R, Borys JM, Sinnett D, Marcil V, Levy E. Nutriepigenomics and malnutrition. Epigenomics 2017; 9:893-917. [DOI: 10.2217/epi-2016-0168] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Epigenetics is defined as the modulation of gene expression without changes to the underlying DNA sequence. Epigenetic alterations, as a consequence of in utero malnutrition, may play a role in susceptibility to develop adulthood diseases and inheritance. However, the mechanistic link between epigenetic modifications and abnormalities in nutrition remains elusive. This review provides an update on the association of suboptimal nutritional environment and the high propensity to produce adult-onset chronic illnesses with a particular focus on modifications in genome functions that occur without alterations to the DNA sequence. We will mention the drivers of the phenotype and pattern of epigenetic markers set down during the reprogramming along with novel preventative and therapeutic strategies. New knowledge of epigenetic alterations is opening a gate toward personalized medicine.
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Affiliation(s)
- Arnaud de Luca
- Research Center, Sainte-Justine University Hospital Center, Montreal, Quebec H3T 1C5, Canada
- INSERM, U 1069, F-37044 Tours, France
| | - Regis Hankard
- INSERM, U 1069, F-37044 Tours, France
- François Rabelais University, F-37000 Tours, France
| | | | - Daniel Sinnett
- Research Center, Sainte-Justine University Hospital Center, Montreal, Quebec H3T 1C5, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - Valérie Marcil
- Research Center, Sainte-Justine University Hospital Center, Montreal, Quebec H3T 1C5, Canada
- Department of Nutrition, Faculty of Medicine, University of Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Emile Levy
- Research Center, Sainte-Justine University Hospital Center, Montreal, Quebec H3T 1C5, Canada
- EPODE International Network, F-75017 Paris, France
- Department of Nutrition, Faculty of Medicine, University of Montréal, Montreal, Quebec H3T 1J4, Canada
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238
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Nica D, Popescu C, Draghici G, Privistirescu I, Suciu M, Stöger R. Effect of cadmium on cytosine hydroxymethylation in gastropod hepatopancreas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:15187-15195. [PMID: 28497329 DOI: 10.1007/s11356-017-9104-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
5-Hydroxymethylcytosine (5hmC) is an important, yet poorly understood epigenetic DNA modification, especially in invertebrates. Aberrant genome-wide 5hmC levels have been associated with cadmium (Cd) exposure in humans, but such information is lacking for invertebrate bioindicators. Here, we aimed to determine whether this epigenetic mark is present in DNA of the hepatopancreas of the land snail Cantareus aspersus and is responsive to Cd exposure. Adult snails were reared under laboratory conditions and exposed to graded amounts of dietary cadmium for 14 days. Weight gain was used as a sublethal endpoint, whereas survival as a lethal endpoint. Our results are the first to provide evidence for the presence of 5hmC in DNA of terrestrial mollusks; 5hmC levels are generally low with the measured values falling below 0.03%. This is also the first study to investigate the interplay of Cd with DNA hydroxymethylation levels in a non-human animal study system. Cadmium retention in the hepatopancreas of C. aspersus increased from a dietary Cd dose of 1 milligram per kilogram dry weight (mg/kg d. wt). For the same treatment, we identified the only significant elevation in percentage of samples with detectable 5hmC levels despite the lack of significant mortalities and changes in weight gain among treatment groups. These findings indicate that 5hmC is an epigenetic mark that may be responsive to Cd exposure, thereby opening a new aspect to invertebrate environmental epigenetics.
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Affiliation(s)
- Dragos Nica
- Faculty of Pharmacy, "Victor Babes" University of Medicine and Pharmacy, P-ta Murgu Eftimie 2, RO 300041, Timisoara, Romania.
- Institute of Life Sciences, "Vasile Goldis" Western University of Arad, Str. Liviu Rebreanu 86, RO 310045, Arad, Romania.
| | - Cristina Popescu
- Institute of Life Sciences, "Vasile Goldis" Western University of Arad, Str. Liviu Rebreanu 86, RO 310045, Arad, Romania
- Faculty of Pharmacy, "Vasile Goldis" Western University of Arad, Str. Liviu Rebreanu 86, RO 310045, Arad, Romania
| | - George Draghici
- Institute of Life Sciences, "Vasile Goldis" Western University of Arad, Str. Liviu Rebreanu 86, RO 310045, Arad, Romania
| | - Ionela Privistirescu
- Faculty of Medicine, "Victor Babes" University of Medicine and Pharmacy, P-ta Murgu Eftimie 2, RO 300041, Timisoara, Romania
| | - Maria Suciu
- Faculty of Pharmacy, "Victor Babes" University of Medicine and Pharmacy, P-ta Murgu Eftimie 2, RO 300041, Timisoara, Romania
- "Babes-Bolyai" University, Str. Mihail Kogalniceanu1, RO 400084, Cluj-Napoca, Romania
| | - Reinhard Stöger
- School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire, LE12 5RD, UK
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239
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Müller T, Müller C. Phenotype of a leaf beetle larva depends on host plant quality and previous test experience. Behav Processes 2017; 142:40-45. [PMID: 28552703 DOI: 10.1016/j.beproc.2017.05.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/28/2017] [Accepted: 05/22/2017] [Indexed: 12/21/2022]
Abstract
Phenotypic expressions of insects are strongly dependent on various external and internal factors, like diet or density and age or sex. However, environmental effects on the behavioural phenotype and repeatability are rather unexplored for holometabolous insects in their larval stage. We examined the effects of the food environment (young versus old cabbage leaves) and previous test experience on growth and behaviour of Phaedon cochleariae larvae. A more nutritious diet, i.e., young leaves, had beneficial consequences on larval growth. Contrary to findings on adults, the behaviour of larvae was neither consistent over time nor across contexts, thus larvae did not show personality. Furthermore, larval behaviour was shaped independent of the diet, pointing to a stage-dependent receptivity towards diet conditions in this species. Besides, larval activity was significantly influenced by former test experience, with naïve larvae being more active than previously tested larvae. In general, in insects memories in an olfactory or sexual behaviour context can lead to behavioural responses later in life. Mechanisms of memory-learning should be further explored in different contexts in insects. Overall, the present study reveals that growth-related traits are diet-dependent and that the activity of a holometabolous larva is shaped in dependence of its previous test experience.
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Affiliation(s)
- Thorben Müller
- Department of Chemical Ecology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
| | - Caroline Müller
- Department of Chemical Ecology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
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240
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Stevens AJ, Rucklidge JJ, Kennedy MA. Epigenetics, nutrition and mental health. Is there a relationship? Nutr Neurosci 2017; 21:602-613. [PMID: 28553986 DOI: 10.1080/1028415x.2017.1331524] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many aspects of human development and disease are influenced by the interaction between genetic and environmental factors. Understanding how our genes respond to the environment is central to managing health and disease, and is one of the major contemporary challenges in human genetics. Various epigenetic processes affect chromosome structure and accessibility of deoxyribonucleic acid (DNA) to the enzymatic machinery that leads to expression of genes. One important epigenetic mechanism that appears to underlie the interaction between environmental factors, including diet, and our genome, is chemical modification of the DNA. The best understood of these modifications is methylation of cytosine residues in DNA. It is now recognized that the pattern of methylated cytosines throughout our genomes (the 'methylome') can change during development and in response to environmental cues, often with profound effects on gene expression. Many dietary constituents may indirectly influence genomic pathways that methylate DNA, and there is evidence for biochemical links between nutritional quality and mental health. Deficiency of both macro- and micronutrients has been associated with increased behavioural problems, and nutritional supplementation has proven efficacious in treatment of certain neuropsychiatric disorders. In this review we examine evidence from the fields of nutrition, developmental biology, and mental health that supports dietary impacts on epigenetic processes, particularly DNA methylation. We then consider whether such processes could underlie the demonstrated efficacy of dietary supplementation in treatment of mental disorders, and whether targeted manipulation of DNA methylation patterns using controlled dietary supplementation may be of wider clinical value.
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Affiliation(s)
- Aaron J Stevens
- a Department of Pathology , University of Otago , P.O. Box 4345, Christchurch , New Zealand
| | - Julia J Rucklidge
- b Department of Psychology , University of Canterbury , Christchurch , New Zealand
| | - Martin A Kennedy
- a Department of Pathology , University of Otago , P.O. Box 4345, Christchurch , New Zealand
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241
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Radhakrishnan S, Literman R, Mizoguchi B, Valenzuela N. MeDIP-seq and nCpG analyses illuminate sexually dimorphic methylation of gonadal development genes with high historic methylation in turtle hatchlings with temperature-dependent sex determination. Epigenetics Chromatin 2017; 10:28. [PMID: 28533820 PMCID: PMC5438563 DOI: 10.1186/s13072-017-0136-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/12/2017] [Indexed: 12/15/2022] Open
Abstract
Background DNA methylation alters gene expression but not DNA sequence and mediates some cases of phenotypic plasticity. Temperature-dependent sex determination (TSD) epitomizes phenotypic plasticity where environmental temperature drives embryonic sexual fate, as occurs commonly in turtles. Importantly, the temperature-specific transcription of two genes underlying gonadal differentiation is known to be induced by differential methylation in TSD fish, turtle and alligator. Yet, how extensive is the link between DNA methylation and TSD remains unclear. Here we test for broad differences in genome-wide DNA methylation between male and female hatchling gonads of the TSD painted turtle Chrysemys picta using methyl DNA immunoprecipitation sequencing, to identify differentially methylated candidates for future study. We also examine the genome-wide nCpG distribution (which affects DNA methylation) in painted turtles and test for historic methylation in genes regulating vertebrate gonadogenesis. Results Turtle global methylation was consistent with other vertebrates (57% of the genome, 78% of all CpG dinucleotides). Numerous genes predicted to regulate turtle gonadogenesis exhibited sex-specific methylation and were proximal to methylated repeats. nCpG distribution predicted actual turtle DNA methylation and was bimodal in gene promoters (as other vertebrates) and introns (unlike other vertebrates). Differentially methylated genes, including regulators of sexual development, had lower nCpG content indicative of higher historic methylation. Conclusions Ours is the first evidence suggesting that sexually dimorphic DNA methylation is pervasive in turtle gonads (perhaps mediated by repeat methylation) and that it targets numerous regulators of gonadal development, consistent with the hypothesis that it may regulate thermosensitive transcription in TSD vertebrates. However, further research during embryogenesis will help test this hypothesis and the alternative that instead, most differential methylation observed in hatchlings is the by-product of sexual differentiation and not its cause. Electronic supplementary material The online version of this article (doi:10.1186/s13072-017-0136-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Srihari Radhakrishnan
- Bioinformatics and Computational Biology Program, Iowa State University, Ames, IA 50011 USA.,Department of Ecology, Evolution and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011 USA
| | - Robert Literman
- Ecology and Evolutionary Biology Program, Iowa State University, Ames, IA 50011 USA.,Department of Ecology, Evolution and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011 USA
| | - Beatriz Mizoguchi
- Interdepartmental Genetics and Genomics Program, Iowa State University, Ames, IA 50011 USA.,Department of Ecology, Evolution and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011 USA
| | - Nicole Valenzuela
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011 USA
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242
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Alternative splicing as a regulator of development and tissue identity. Nat Rev Mol Cell Biol 2017; 18:437-451. [PMID: 28488700 DOI: 10.1038/nrm.2017.27] [Citation(s) in RCA: 771] [Impact Index Per Article: 110.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alternative splicing of eukaryotic transcripts is a mechanism that enables cells to generate vast protein diversity from a limited number of genes. The mechanisms and outcomes of alternative splicing of individual transcripts are relatively well understood, and recent efforts have been directed towards studying splicing networks. It has become apparent that coordinated splicing networks regulate tissue and organ development, and that alternative splicing has important physiological functions in different developmental processes in humans.
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243
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Ye J, Wu W, Li Y, Li L. Influences of the Gut Microbiota on DNA Methylation and Histone Modification. Dig Dis Sci 2017; 62:1155-1164. [PMID: 28341870 DOI: 10.1007/s10620-017-4538-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 03/09/2017] [Indexed: 12/12/2022]
Abstract
The gut microbiota is a vast ensemble of microorganisms inhabiting the mammalian gastrointestinal tract that can impact physiologic and pathologic processes. However, our understanding of the underlying mechanism for the dynamic interaction between host and gut microbiota is still in its infancy. The highly evolved epigenetic modifications allow hosts to reprogram the genome in response to environmental stimuli, which may play a key role in triggering multiple human diseases. In spite of increasing studies in gut microbiota and epigenetic modifications, the correlation between them has not been well elaborated. Here, we review current knowledge of gut microbiota impacts on epigenetic modifications, the major evidence of which centers on DNA methylation and histone modification of the immune system.
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Affiliation(s)
- Jianzhong Ye
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310003, China
| | - Wenrui Wu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310003, China
| | - Yating Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310003, China
| | - Lanjuan Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310003, China.
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244
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Strachecka A, Chobotow J, Paleolog J, Łoś A, Schulz M, Teper D, Kucharczyk H, Grzybek M. Insights into the biochemical defence and methylation of the solitary bee Osmia rufa L: A foundation for examining eusociality development. PLoS One 2017; 12:e0176539. [PMID: 28448564 PMCID: PMC5407852 DOI: 10.1371/journal.pone.0176539] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 04/12/2017] [Indexed: 01/24/2023] Open
Abstract
We examined age-related biochemical and histological changes in the fat bodies and hemolymph of Osmia rufa males and females. We analysed solitary bees during diapause, in October and in April; as well as the flying insects following diapause, in May and June. The trophocyte sizes, as well as the numbers of lipid droplets were the greatest at the beginning of diapause. Subsequently, they decreased along with age. Triglyceride and glucose concentrations systematically decreased in fat body cells but increased in the hemolymph from October to June. Concentrations/activities of (enzymatic and non-enzymatic) antioxidant and proteolytic systems, as well as phenoloxidase, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase levels were constant during the diapause, usually lower in the males than the females. Prior to the diapause/overwintering, the concentrations/activities of all the compounds were higher in the fat bodies than in the hemolymph. Later in the spring and in the summer, they increased in the hemolymph and on the body surfaces, while decreasing in the fat bodies. The global DNA methylation levels increased with age. Higher levels were always observed in the males than in the females. The study will promote better understanding of bee evolution and will be useful for the protection and management of solitary bees, with benefits to the environment and agriculture.
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Affiliation(s)
- Aneta Strachecka
- Department of Biological Basis of Animal Production, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, Lublin, Poland
| | - Jacek Chobotow
- Zoological Museum/Laboratory, Institute of Biology and Biochemistry, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19, Lublin, Poland
| | - Jerzy Paleolog
- Department of Zoology, Animal Ecology & Wildlife Management, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, Lublin, Poland
| | - Aleksandra Łoś
- Department of Biological Basis of Animal Production, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, Lublin, Poland
| | - Michał Schulz
- Department of Biological Basis of Animal Production, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, Lublin, Poland
| | - Dariusz Teper
- Research Institute of Horticulture, Apicultural Division in Pulawy, Kazimierska 2, Pulawy, Poland
| | - Halina Kucharczyk
- Department of Zoology, Institute of Biology and Biochemistry, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19, Lublin, Poland
| | - Maciej Grzybek
- Department of Parasitology and Invasive Diseases, Faculty of Veterinary Medicine University of Life Sciences in Lublin, Akademicka 12, Lublin, Poland
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Science in Jastrzebiec, Postepu 36A, Magdalenka, Poland
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245
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Cridge AG, Lovegrove MR, Skelly JG, Taylor SE, Petersen GEL, Cameron RC, Dearden PK. The honeybee as a model insect for developmental genetics. Genesis 2017; 55. [PMID: 28432809 DOI: 10.1002/dvg.23019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 01/08/2017] [Accepted: 01/15/2017] [Indexed: 11/11/2022]
Abstract
Honeybees are an important component of modern agricultural systems, and a fascinating and scientifically engrossing insect. Honeybees are not commonly used as model systems for understanding development in insects despite their importance in agriculture. Honeybee embryogenesis, while being superficially similar to Drosophila, is molecularly very different, especially in axis formation and sex determination. In later development, much of honeybee biology is modified by caste development, an as yet poorly understood, but excellent, system to study developmental plasticity. In adult stages, developmental plasticity of the ovaries, related to reproductive constraint exhibits another aspect of plasticity. Here they review the tools, current knowledge and opportunities in honeybee developmental biology, and provide an updated embryonic staging scheme to support future studies.
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Affiliation(s)
- A G Cridge
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand
| | - M R Lovegrove
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand
| | - J G Skelly
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand
| | - S E Taylor
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand
| | - G E L Petersen
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand.,AbacusBio Ltd, Public Trust Building, 442 Moray Place, Dunedin 9016, Aotearoa-New Zealand
| | - R C Cameron
- Department of Developmental and Molecular Biology and Gottesman Institute for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York
| | - P K Dearden
- Laboratory for Evolution and Development, Genetics Otago, Biochemistry Department, University of Otago, Dunedin, 9054, P.O. Box 56, Aotearoa-New Zealand
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246
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Leung C, Duclos KK, Grünbaum T, Cloutier R, Angers B. Asymmetry in dentition and shape of pharyngeal arches in the clonal fish Chrosomus eos-neogaeus: Phenotypic plasticity and developmental instability. PLoS One 2017; 12:e0174235. [PMID: 28380079 PMCID: PMC5381790 DOI: 10.1371/journal.pone.0174235] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 03/06/2017] [Indexed: 01/15/2023] Open
Abstract
The effect of the environment may result in different developmental outcomes. Extrinsic signals can modify developmental pathways and result in alternative phenotypes (phenotypic plasticity). The environment can also be interpreted as a stressor and increase developmental instability (developmental noise). Directional and fluctuating asymmetry provide a conceptual background to discriminate between these results. This study aims at assessing whether variation in dentition and shape of pharyngeal arches of the clonal fish Chrosomus eos-neogaeus results from developmental instability or environmentally induced changes. A total of 262 specimens of the Chrosomus eos-neogaeus complex from 12 natural sites were analysed. X-ray microcomputed tomography (X-ray micro-CT) was used to visualize the pharyngeal arches in situ with high resolution. Variation in the number of pharyngeal teeth is high in hybrids in contrast to the relative stability observed in both parental species. The basal dental formula is symmetric while the most frequent alternative dental formula is asymmetric. Within one lineage, large variation in the proportion of individuals bearing basal or alternative dental formulae was observed among sites in the absence of genetic difference. Both dentition and arch shape of this hybrid lineage were explained significantly by environmental differences. Only individuals bearing asymmetric dental formula displayed fluctuating asymmetry as well as directional left-right asymmetry for the arches. The hybrids appeared sensitive to environmental signals and intraspecific variation on pharyngeal teeth was not random but reflects phenotypic plasticity. Altogether, these results support the influence of the environment as a trigger for an alternative developmental pathway resulting in left-right asymmetry in dentition and shape of pharyngeal arches.
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Affiliation(s)
- Christelle Leung
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Kevin Karl Duclos
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Thomas Grünbaum
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Richard Cloutier
- Département de Biologie, Chimie et Géographie, Université du Québec à Rimouski, Rimouski, Quebec, Canada
| | - Bernard Angers
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
- * E-mail:
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247
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Developmental origins of type 2 diabetes: a perspective from China. Eur J Clin Nutr 2017; 71:870-880. [PMID: 28378847 DOI: 10.1038/ejcn.2017.48] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 03/04/2017] [Indexed: 12/20/2022]
Abstract
There has been a marked increase in the prevalence of diabetes in Asia, including China, over the last few decades. While the increased prevalence of diabetes has often been attributed to the nutritional transition associated with recent economic development, emerging data suggest that early-life exposures also play a major role in shaping developmental trajectories, and contributes to alter an individual's susceptibility to diabetes and other non-communicable diseases (NCDs). Early-life exposures such as in utero exposure to undernutrition has been consistently linked with later risk of diabetes and obesity. Furthermore, in utero exposure to maternal hyperglycemia, maternal obesity and excess gestational weight gain are all linked with increased childhood obesity and later risk of diabetes. Emerging data have also highlighted the potential link between early-feeding practices, the role of one-carbon metabolism in metabolic programming and endocrine disrupting chemicals (EDCs) with later risk of diabetes. These different developmental exposures may all be highly relevant to the current epidemic of diabetes in China. For example, the prevalence of gestational diabetes has increased markedly over the last two decades, and may contribute to the diabetes epidemic by driving macrosomia, childhood obesity and later risk of diabetes. In order to address the current burden of diabetes, a lifecourse perspective, incorporating multisectoral efforts from public health policy down to the individuals, will be needed. Several major initiatives have been launched in China as part of its national plans for NCD prevention and treatment, and the experience from these efforts would be invaluable.
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248
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Bharadwaj PS, Hall SE. Endogenous RNAi Pathways Are Required in Neurons for Dauer Formation in Caenorhabditis elegans. Genetics 2017; 205:1503-1516. [PMID: 28122825 PMCID: PMC5378109 DOI: 10.1534/genetics.116.195438] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 01/21/2017] [Indexed: 12/16/2022] Open
Abstract
Animals can adapt to unfavorable environments through changes in physiology or behavior. In the nematode, Caenorhabditis elegans, environmental conditions perceived early in development determine whether the animal enters either the reproductive cycle, or enters into an alternative diapause stage named dauer. Here, we show that endogenous RNAi pathways play a role in dauer formation in crowding (high pheromone), starvation, and high temperature conditions. Disruption of the Mutator proteins or the nuclear Argonaute CSR-1 result in differential dauer-deficient phenotypes that are dependent upon the experienced environmental stress. We provide evidence that the RNAi pathways function in chemosensory neurons for dauer formation, upstream of the TGF-β and insulin signaling pathways. In addition, we show that Mutator MUT-16 expression in a subset of individual pheromone-sensing neurons is sufficient for dauer formation in high pheromone conditions, but not in starvation or high temperature conditions. Furthermore, we also show that MUT-16 and CSR-1 are required for expression of a subset of G proteins with functions in the detection of pheromone components. Together, our data suggest a model where Mutator-amplified siRNAs that associate with the CSR-1 pathway promote expression of genes required for the detection and signaling of environmental conditions to regulate development and behavior in C. elegans This study highlights a mechanism whereby RNAi pathways mediate the link between environmental stress and adaptive phenotypic plasticity in animals.
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Affiliation(s)
| | - Sarah E Hall
- Department of Biology, Syracuse University, New York 13244
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249
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Yang W, Tian Y, Han M, Miao X. Longevity extension of worker honey bees ( Apis mellifera) by royal jelly: optimal dose and active ingredient. PeerJ 2017; 5:e3118. [PMID: 28367370 PMCID: PMC5372980 DOI: 10.7717/peerj.3118] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 02/23/2017] [Indexed: 12/18/2022] Open
Abstract
In the Western honey bee, Apis mellifera, queens and workers have different longevity although they share the same genome. Queens consume royal jelly (RJ) as the main food throughout their life, including as adults, but workers only eat worker jelly when they are larvae less than 3 days old. In order to explore the effect of RJ and the components affecting longevity of worker honey bees, we first determined the optimal dose for prolonging longevity of workers as 4% RJ in 50% sucrose solution, and developed a method of obtaining long lived workers. We then compared the effects of longevity extension by RJ 4% with bee-collected pollen from rapeseed (Brassica napus). Lastly, we determined that a water soluble RJ protein obtained by precipitation with 60% ammonium sulfate (RJP60) contained the main component for longevity extension after comparing the effects of RJ crude protein extract (RJCP), RJP30 (obtained by precipitation with 30% ammonium sulfate), and RJ ethanol extract (RJEE). Understanding what regulates worker longevity has potential to help increase colony productivity and improve crop pollination efficiency.
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Affiliation(s)
- Wenchao Yang
- Apitherapy Institute, College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, China.,Bee Product Processing and Application Research Center of the Ministry of Education, Fuzhou, China
| | - Yuanyuan Tian
- Apitherapy Institute, College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, China.,Bee Product Processing and Application Research Center of the Ministry of Education, Fuzhou, China
| | - Mingfeng Han
- Apitherapy Institute, College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, China.,Bee Product Processing and Application Research Center of the Ministry of Education, Fuzhou, China
| | - Xiaoqing Miao
- Apitherapy Institute, College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, China.,Bee Product Processing and Application Research Center of the Ministry of Education, Fuzhou, China
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250
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Wedd L, Ashby R, Foret S, Maleszka R. Developmental and loco-like effects of a swainsonine-induced inhibition of α-mannosidase in the honey bee, Apis mellifera. PeerJ 2017; 5:e3109. [PMID: 28321369 PMCID: PMC5357340 DOI: 10.7717/peerj.3109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 02/20/2017] [Indexed: 01/24/2023] Open
Abstract
Background Deficiencies in lysosomal a-mannosidase (LAM) activity in animals, caused either by mutations or by consuming toxic alkaloids, lead to severe phenotypic and behavioural consequences. Yet, epialleles adversely affecting LAM expression exist in the honey bee population suggesting that they might be beneficial in certain contexts and cannot be eliminated by natural selection. Methods We have used a combination of enzymology, molecular biology and metabolomics to characterise the catalytic properties of honey bee LAM (AmLAM) and then used an indolizidine alkaloid swainsonine to inhibit its activity in vitro and in vivo. Results We show that AmLAM is inhibited in vitro by swainsonine albeit at slightly higher concentrations than in other animals. Dietary exposure of growing larvae to swainsonine leads to pronounced metabolic changes affecting not only saccharides, but also amino acids, polyols and polyamines. Interestingly, the abundance of two fatty acids implicated in epigenetic regulation is significantly reduced in treated individuals. Additionally, swainsonie causes loco-like symptoms, increased mortality and a subtle decrease in the rate of larval growth resulting in a subsequent developmental delay in pupal metamorphosis. Discussion We consider our findings in the context of cellular LAM function, larval development, environmental toxicity and colony-level impacts. The observed developmental heterochrony in swainsonine-treated larvae with lower LAM activity offer a plausible explanation for the existence of epialleles with impaired LAM expression. Individuals carrying such epialleles provide an additional level of epigenetic diversity that could be beneficial for the functioning of a colony whereby more flexibility in timing of adult emergence might be useful for task allocation.
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Affiliation(s)
- Laura Wedd
- Research School of Biology, Australian National University , Canberra , Australia
| | - Regan Ashby
- Research School of Biology, Australian National University, Canberra, Australia; Centre for Research in Therapeutic Solutions, Health Research Institute, Faculty of Education, Science, Technology and Mathematics, University of Canberra, Canberra, Australia
| | - Sylvain Foret
- Research School of Biology, Australian National University , Canberra , Australia
| | - Ryszard Maleszka
- Research School of Biology, Australian National University , Canberra , Australia
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