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Bartling MT, Brandt A, Hollert H, Vilcinskas A. Current Insights into Sublethal Effects of Pesticides on Insects. Int J Mol Sci 2024; 25:6007. [PMID: 38892195 PMCID: PMC11173082 DOI: 10.3390/ijms25116007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/25/2024] [Accepted: 05/27/2024] [Indexed: 06/21/2024] Open
Abstract
The effect of pesticides on insects is often discussed in terms of acute and chronic toxicity, but an important and often overlooked aspect is the impact of sublethal doses on insect physiology and behavior. Pesticides can influence various physiological parameters of insects, including the innate immune system, development, and reproduction, through a combination of direct effects on specific exposed tissues and the modification of behaviors that contribute to health and reproductive success. Such behaviors include mobility, feeding, oviposition, navigation, and the ability to detect pheromones. Pesticides also have a profound effect on insect learning and memory. The precise effects depend on many different factors, including the insect species, age, sex, caste, physiological condition, as well as the type and concentration of the active ingredients and the exposure route. More studies are needed to assess the effects of different active ingredients (and combinations thereof) on a wider range of species to understand how sublethal doses of pesticides can contribute to insect decline. This review reflects our current knowledge about sublethal effects of pesticides on insects and advancements in the development of innovative methods to detect them.
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Affiliation(s)
- Merle-Theresa Bartling
- Institute for Insect Biotechnology, Justus Liebig University of Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany;
| | - Annely Brandt
- Bee Institute Kirchhain, Landesbetrieb Landwirtschaft Hessen, Erlenstr. 9, 35274 Kirchhain, Germany;
| | - Henner Hollert
- Department Evolutionary Ecology & Environmental Toxicology, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany;
- Department Environmental Media Related Ecotoxicology, Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, 57392 Schmallenberg, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325 Frankfurt, Germany
| | - Andreas Vilcinskas
- Institute for Insect Biotechnology, Justus Liebig University of Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany;
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325 Frankfurt, Germany
- Branch of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, 35392 Giessen, Germany
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2
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Geens B, Goossens S, Li J, Van de Peer Y, Vanden Broeck J. Untangling the gordian knot: The intertwining interactions between developmental hormone signaling and epigenetic mechanisms in insects. Mol Cell Endocrinol 2024; 585:112178. [PMID: 38342134 DOI: 10.1016/j.mce.2024.112178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/30/2024] [Accepted: 02/04/2024] [Indexed: 02/13/2024]
Abstract
Hormones control developmental and physiological processes, often by regulating the expression of multiple genes simultaneously or sequentially. Crosstalk between hormones and epigenetics is pivotal to dynamically coordinate this process. Hormonal signals can guide the addition and removal of epigenetic marks, steering gene expression. Conversely, DNA methylation, histone modifications and non-coding RNAs can modulate regional chromatin structure and accessibility and regulate the expression of numerous (hormone-related) genes. Here, we provide a review of the interplay between the classical insect hormones, ecdysteroids and juvenile hormones, and epigenetics. We summarize the mode-of-action and roles of these hormones in post-embryonic development, and provide a general overview of epigenetic mechanisms. We then highlight recent advances on the interactions between these hormonal pathways and epigenetics, and their involvement in development. Furthermore, we give an overview of several 'omics techniques employed in the field. Finally, we discuss which questions remain unanswered and possible avenues for future research.
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Affiliation(s)
- Bart Geens
- Molecular Developmental Physiology and Signal Transduction, KU Leuven, Naamsestraat 59 box 2465, B-3000 Leuven, Belgium.
| | - Stijn Goossens
- Molecular Developmental Physiology and Signal Transduction, KU Leuven, Naamsestraat 59 box 2465, B-3000 Leuven, Belgium.
| | - Jia Li
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; VIB Center for Plant Systems Biology, VIB, Ghent, Belgium.
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; VIB Center for Plant Systems Biology, VIB, Ghent, Belgium.
| | - Jozef Vanden Broeck
- Molecular Developmental Physiology and Signal Transduction, KU Leuven, Naamsestraat 59 box 2465, B-3000 Leuven, Belgium.
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3
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Brink K, Thomas CL, Jones A, Chan TW, Mallon EB. Exploring the ageing methylome in the model insect, Nasonia vitripennis. BMC Genomics 2024; 25:305. [PMID: 38519892 PMCID: PMC10958858 DOI: 10.1186/s12864-024-10211-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/11/2024] [Indexed: 03/25/2024] Open
Abstract
BACKGROUND The ageing process is a multifaceted phenomenon marked by the gradual deterioration of cellular and organismal functions, accompanied by an elevated susceptibility to diseases. The intricate interplay between genetic and environmental factors complicates research, particularly in complex mammalian models. In this context, simple invertebrate organisms have been pivotal, but the current models lack detectable DNA methylation limiting the exploration of this critical epigenetic ageing mechanism. This study introduces Nasonia vitripennis, the jewel wasp, as an innovative invertebrate model for investigating the epigenetics of ageing. Leveraging its advantages as a model organism and possessing a functional DNA methylation system, Nasonia emerges as a valuable addition to ageing research. RESULTS Whole-genome bisulfite sequencing unveiled dynamic alterations in DNA methylation, with differentially methylated CpGs between distinct time points in both male and female wasps. These changes were associated with numerous genes, enriching for functions related to telomere maintenance, histone methylation, and mRNA catabolic processes. Additionally, other CpGs were found to be variably methylated at each timepoint. Sex-specific effects on epigenetic entropy were observed, indicating differential patterns in the loss of epigenetic stability over time. Constructing an epigenetic clock containing 19 CpGs revealed a robust correlation between epigenetic age and chronological age. CONCLUSIONS Nasonia vitripennis emerges as a promising model for investigating the epigenetics of ageing, shedding light on the intricate dynamics of DNA methylation and their implications for age-related processes. This research not only expands the repertoire of ageing models but also opens avenues for deeper exploration of epigenetic mechanisms in the context of ageing.
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Affiliation(s)
- K Brink
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, UK
| | - C L Thomas
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, UK
| | - A Jones
- Institute for Evolution and Biodiversity, University of Muenster, Huefferstrabe, Muenster, Germany
| | - T W Chan
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, UK
| | - E B Mallon
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, UK.
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4
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Taylor BA, Taylor D, Bodrug‐Schepers A, Câmara Ferreira F, Stralis‐Pavese N, Himmelbauer H, Guigó R, Reuter M, Sumner S. Molecular signatures of alternative reproductive strategies in a facultatively social hover wasp. Mol Ecol 2024; 33:e17217. [PMID: 38014715 PMCID: PMC10953455 DOI: 10.1111/mec.17217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 11/09/2023] [Accepted: 11/13/2023] [Indexed: 11/29/2023]
Abstract
Social insect reproductives and non-reproductives represent ideal models with which to understand the expression and regulation of alternative phenotypes. Most research in this area has focused on the developmental regulation of reproductive phenotypes in obligately social taxa such as honey bees, while relatively few studies have addressed the molecular correlates of reproductive differentiation in species in which the division of reproductive labour is established only in plastic dominance hierarchies. To address this knowledge gap, we generate the first genome for any stenogastrine wasp and analyse brain transcriptomic data for non-reproductives and reproductives of the facultatively social species Liostenogaster flavolineata, a representative of one of the simplest forms of social living. By experimentally manipulating the reproductive 'queues' exhibited by social colonies of this species, we show that reproductive division of labour in this species is associated with transcriptomic signatures that are more subtle and variable than those observed in social taxa in which colony living has become obligate; that variation in gene expression among non-reproductives reflects their investment into foraging effort more than their social rank; and that genes associated with reproductive division of labour overlap to some extent with those underlying division of labour in the separate polistine origin of wasp sociality but only explain a small portion of overall variation in this trait. These results indicate that broad patterns of within-colony transcriptomic differentiation in this species are similar to those in Polistinae but offer little support for the existence of a strongly conserved 'toolkit' for sociality.
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Affiliation(s)
- Benjamin A. Taylor
- Centre for Biodiversity & Environment ResearchUniversity College LondonLondonUK
- Department of Genetics, Evolution & EnvironmentUniversity College LondonLondonUK
| | - Daisy Taylor
- School of Biological SciencesUniversity of BristolBristolUK
| | | | | | - Nancy Stralis‐Pavese
- Department of BiotechnologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Heinz Himmelbauer
- Department of BiotechnologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Roderic Guigó
- Centre for Genomic RegulationBarcelona Institute of Science and TechnologyBarcelonaSpain
- Universitat Pompeu FabraBarcelonaSpain
| | - Max Reuter
- Department of Genetics, Evolution & EnvironmentUniversity College LondonLondonUK
- Centre for Life's Origins and EvolutionUniversity College LondonLondonUK
| | - Seirian Sumner
- Centre for Biodiversity & Environment ResearchUniversity College LondonLondonUK
- Department of Genetics, Evolution & EnvironmentUniversity College LondonLondonUK
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5
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Renard T, Martinet B, De Souza Araujo N, Aron S. DNA methylation extends lifespan in the bumblebee Bombus terrestris. Proc Biol Sci 2023; 290:20232093. [PMID: 38052245 DOI: 10.1098/rspb.2023.2093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 11/14/2023] [Indexed: 12/07/2023] Open
Abstract
Epigenetic alterations are a primary hallmark of ageing. In mammals, age-related epigenetic changes alter gene expression profiles, disrupt cellular homeostasis and physiological functions and, therefore, promote ageing. It remains unclear whether ageing is also driven by epigenetic mechanisms in invertebrates. Here, we used a pharmacological hypomethylating agent (RG108) to evaluate the effects of DNA methylation (DNAme) on lifespan in an insect-the bumblebee Bombus terrestris. RG108 extended mean lifespan by 43% and induced the differential methylation of genes involved in hallmarks of ageing, including DNA damage repair and chromatin organization. Furthermore, the longevity gene sirt1 was overexpressed following the treatment. Functional experiments demonstrated that SIRT1 protein activity was positively associated with lifespan. Overall, our study indicates that epigenetic mechanisms are conserved regulators of lifespan in both vertebrates and invertebrates and provides new insights into how DNAme is involved in the ageing process in insects.
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Affiliation(s)
- Thibaut Renard
- Evolutionary Biology & Ecology, Université Libre de Bruxelles, Avenue Paul Héger - CP 160/12, Bruxelles 1000, Belgium
| | - Baptiste Martinet
- Evolutionary Biology & Ecology, Université Libre de Bruxelles, Avenue Paul Héger - CP 160/12, Bruxelles 1000, Belgium
| | - Natalia De Souza Araujo
- Evolutionary Biology & Ecology, Université Libre de Bruxelles, Avenue Paul Héger - CP 160/12, Bruxelles 1000, Belgium
| | - Serge Aron
- Evolutionary Biology & Ecology, Université Libre de Bruxelles, Avenue Paul Héger - CP 160/12, Bruxelles 1000, Belgium
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6
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Rahman SR, Lozier JD. Genome-wide DNA methylation patterns in bumble bee (Bombus vosnesenskii) populations from spatial-environmental range extremes. Sci Rep 2023; 13:14901. [PMID: 37689750 PMCID: PMC10492822 DOI: 10.1038/s41598-023-41896-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 09/01/2023] [Indexed: 09/11/2023] Open
Abstract
Unraveling molecular mechanisms of adaptation to complex environments is crucial to understanding tolerance of abiotic pressures and responses to climatic change. Epigenetic variation is increasingly recognized as a mechanism that can facilitate rapid responses to changing environmental cues. To investigate variation in genetic and epigenetic diversity at spatial and thermal extremes, we use whole genome and methylome sequencing to generate a high-resolution map of DNA methylation in the bumble bee Bombus vosnesenskii. We sample two populations representing spatial and environmental range extremes (a warm southern low-elevation site and a cold northern high-elevation site) previously shown to exhibit differences in thermal tolerance and determine positions in the genome that are consistently and variably methylated across samples. Bisulfite sequencing reveals methylation characteristics similar to other arthropods, with low global CpG methylation but high methylation concentrated in gene bodies and in genome regions with low nucleotide diversity. Differentially methylated sites (n = 2066) were largely hypomethylated in the northern high-elevation population but not related to local sequence differentiation. The concentration of methylated and differentially methylated sites in exons and putative promoter regions suggests a possible role in gene regulation, and this high-resolution analysis of intraspecific epigenetic variation in wild Bombus suggests that the function of methylation in niche adaptation would be worth further investigation.
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Affiliation(s)
| | - Jeffrey D Lozier
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA
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7
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Okwaro LA, Korb J. Epigenetic regulation and division of labor in social insects. CURRENT OPINION IN INSECT SCIENCE 2023; 58:101051. [PMID: 37164259 DOI: 10.1016/j.cois.2023.101051] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 05/01/2023] [Accepted: 05/02/2023] [Indexed: 05/12/2023]
Abstract
Analogous to multicellular organisms, social insect colonies are characterized by division of labor with queens and workers reflecting germline and soma, respectively. In multicellular organisms, such division is achieved through epigenetic factors regulating cell differentiation during development. Analogously, epigenetic regulation is postulated to regulate caste differences in social insects. We summarize recent findings about the role of epigenetics in social insects, focusing on DNA methylation and histone modifications. We specifically address (i) queen versus worker caste differentiation, (ii) queen versus worker caste differences, and (iii) division of labor among workers. Our review provides an overview of an exciting and controversially discussed field in developmental and molecular biology. It shows that our current understanding about the role of epigenetics in regulating division of labor in social insects is still fragmentary but that refined methods with well-replicated samples and targeted questions offer promising insights into this emerging field of socio-epigenomics.
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Affiliation(s)
- Louis A Okwaro
- University of Freiburg, Evolutionary Biology and Ecology D-79104 Freiburg, Germany
| | - Judith Korb
- University of Freiburg, Evolutionary Biology and Ecology D-79104 Freiburg, Germany.
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8
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Toga K, Bono H. Meta-Analysis of Public RNA Sequencing Data Revealed Potential Key Genes Associated with Reproductive Division of Labor in Social Hymenoptera and Termites. Int J Mol Sci 2023; 24:ijms24098353. [PMID: 37176060 PMCID: PMC10179490 DOI: 10.3390/ijms24098353] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
Eusociality in insects has evolved independently many times. One of the most notable characteristics of eusociality is the reproductive division of labor. In social insects, the reproductive division of labor is accomplished by queens and workers. Transcriptome analyses of queens and workers have been conducted for various eusocial species. However, the genes that regulate the reproductive division of labor across all or multiple eusocial species have not yet been fully elucidated. Therefore, we conducted a meta-analysis using publicly available RNA-sequencing data from four major groups of social insects. In this meta-analysis, we collected 258 pairs (queen vs. worker) of RNA-sequencing data from 34 eusocial species. The meta-analysis identified a total of 20 genes that were differentially expressed in queens or workers. Out of these, 12 genes have not previously been reported to be involved in the reproductive division of labor. Functional annotation of these 20 genes in other organisms revealed that they could be regulators of behaviors and physiological states related to the reproductive division of labor. These 20 genes, revealed using massive datasets of numerous eusocial insects, may be key regulators of the reproductive division of labor.
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Affiliation(s)
- Kouhei Toga
- Laboratory of BioDX, PtBio Co-Creation Research Center, Genome Editing Innovation Center, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima City 739-0046, Hiroshima, Japan
- Laboratory of Genome Informatics, Graduate School of Integrated Sciences for Life, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima City 739-0046, Hiroshima, Japan
| | - Hidemasa Bono
- Laboratory of BioDX, PtBio Co-Creation Research Center, Genome Editing Innovation Center, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima City 739-0046, Hiroshima, Japan
- Laboratory of Genome Informatics, Graduate School of Integrated Sciences for Life, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima City 739-0046, Hiroshima, Japan
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9
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Zhou Z, Yao Z, Abouzaid M, Hull JJ, Ma W, Hua H, Lin Y. Co-Expression Network Analysis: A Future Approach for Pest Control Target Discovery. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:7201-7209. [PMID: 37146201 DOI: 10.1021/acs.jafc.3c00113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The striped stem borer (SSB, Chilo suppressalis Walker) is a major pest of rice worldwide. Double-stranded RNAs (dsRNAs) targeting essential genes can trigger a lethal RNA interference (RNAi) response in insect pests. In this study, we applied a Weighted Gene Co-expression Network Analysis (WGCNA) to diet-based RNA-Seq data as a method to facilitate the discovery of novel target genes for pest control. Nieman-Pick type c 1 homolog b (NPC1b) was identified as the gene with the highest correlation values to hemolymph cholesterol levels and larval size. Functional characterization of the gene supported CsNPC1b expression with dietary cholesterol uptake and insect growth. This study revealed the critical role of NPC1b for intestinal cholesterol absorption in lepidopteran insects and highlights the utility of the WGCNA approach for identifying new pest management targets.
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Affiliation(s)
- Zaihui Zhou
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhuotian Yao
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Mostafa Abouzaid
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - J Joe Hull
- Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, Arizona 85138, United States
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Hongxia Hua
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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10
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Degueldre F, Aron S. Long-term sperm storage in eusocial Hymenoptera. Biol Rev Camb Philos Soc 2023; 98:567-583. [PMID: 36397639 DOI: 10.1111/brv.12919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 10/29/2022] [Accepted: 11/01/2022] [Indexed: 11/21/2022]
Abstract
In internally fertilizing species, sperm transfer is not always immediately followed by egg fertilization, and female sperm storage (FSS) may occur. FSS is a phenomenon in which females store sperm in a specialized organ for periods lasting from a few hours to several years, depending on the species. Eusocial hymenopterans (ants, social bees, and social wasps) hold the record for FSS duration. In these species, mating takes place during a single nuptial flight that occurs early in adult life for both sexes; they never mate again. Males die quickly after copulation but survive posthumously as sperm stored in their mates' spermathecae. Reproductive females, also known as queens, have a much longer life expectancy, up to 20 years in some species. Here, we review what is currently known about the molecular adaptations underlying the remarkable FSS capacities in eusocial hymenopterans. Because sperm quality is crucial to the reproductive success of both sexes, we also discuss the mechanisms involved in sperm storage and preservation in the male seminal vesicles prior to ejaculation. Finally, we propose future research directions that should broaden our understanding of this unique biological phenomenon.
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Affiliation(s)
- Félicien Degueldre
- Evolutionary Biology and Ecology, CP 160/12, Université Libre de Bruxelles, B-1050, Brussels, Belgium
| | - Serge Aron
- Evolutionary Biology and Ecology, CP 160/12, Université Libre de Bruxelles, B-1050, Brussels, Belgium
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11
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Renard T, Gueydan C, Aron S. DNA methylation and expression of the egfr gene are associated with worker size in monomorphic ants. Sci Rep 2022; 12:21228. [PMID: 36481802 PMCID: PMC9732050 DOI: 10.1038/s41598-022-25675-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
The reproductive division of labour is a hallmark of eusocial Hymenoptera. Females are either reproductive queens or non-reproductive workers. In ants, workers often display further task specialisation that is associated with variation in size and/or morphology. Because female polyphenism is typically under environmental control, it is thought epigenetic mechanisms (such as DNA methylation) play a central role since they mediate gene-by-environment interactions. Methylation of the growth-promoting gene epidermal growth factor receptor (egfr) was indeed shown to control worker size in a highly polymorphic ant. However, it remains unknown if egfr methylation could also regulate worker size in monomorphic species. By combining experimental pharmacology and molecular biology, we show that worker size is associated with egfr methylation in two monomorphic ants. Furthermore, we functionally demonstrate that EGFR signalling affects worker size. These results indicate that worker size regulation by egfr methylation has been mechanistically conserved in ants but remains unexploited in monomorphic species.
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Affiliation(s)
- Thibaut Renard
- grid.4989.c0000 0001 2348 0746Evolutionary Biology and Ecology, Université Libre de Bruxelles, Avenue F.D. Roosevelt, 50, 1050 Brussels, Belgium
| | - Cyril Gueydan
- grid.4989.c0000 0001 2348 0746Molecular Biology of the Gene, Université Libre de Bruxelles, Rue Prof. Jeener et Brachet, 12, 6041 Gosselies, Belgium
| | - Serge Aron
- grid.4989.c0000 0001 2348 0746Evolutionary Biology and Ecology, Université Libre de Bruxelles, Avenue F.D. Roosevelt, 50, 1050 Brussels, Belgium
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12
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Feldmeyer B, Gstöttl C, Wallner J, Jongepier E, Séguret A, Grasso DA, Bornberg-Bauer E, Foitzik S, Heinze J. Evidence for a conserved queen-worker genetic toolkit across slave-making ants and their ant hosts. Mol Ecol 2022; 31:4991-5004. [PMID: 35920076 DOI: 10.1111/mec.16639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 07/04/2022] [Accepted: 07/08/2022] [Indexed: 11/30/2022]
Abstract
The ecological success of social Hymenoptera (ants, bees, wasps) depends on the division of labour between the queen and workers. Each caste exhibits highly specialised morphology, behaviour, and life-history traits, such as lifespan and fecundity. Despite strong defences against alien intruders, insect societies are vulnerable to social parasites, such as workerless inquilines or slave-making ants. Here, we investigate whether gene expression varies in parallel ways between lifestyles (slave-making versus host ants) across five independent origins of ant slavery in the "Formicoxenus-group" of the ant tribe Crematogastrini. As caste differences are often less pronounced in slave-making ants than in non-parasitic ants, we also compare caste-specific gene expression patterns between lifestyles. We demonstrate a substantial overlap in expression differences between queens and workers across taxa, irrespective of lifestyle. Caste affects the transcriptomes much more profoundly than lifestyle, as indicated by 37 times more genes being linked to caste than to lifestyle and by multiple caste-associated modules of co-expressed genes with strong connectivity. However, several genes and one gene module are linked to slave-making across the independent origins of this parasitic lifestyle, pointing to some evolutionary convergence. Finally, we do not find evidence for an interaction between caste and lifestyle, indicating that caste differences in gene expression remain consistent even when species switch to a parasitic lifestyle. Our findings strongly support the existence of a core set of genes whose expression is linked to the queen and worker caste in this ant taxon, as proposed by the "genetic toolkit" hypothesis.
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Affiliation(s)
- B Feldmeyer
- Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
| | - C Gstöttl
- Zoology / Evolutionary Biology, University of Regensburg, Regensburg, Germany
| | - J Wallner
- Zoology / Evolutionary Biology, University of Regensburg, Regensburg, Germany
| | - E Jongepier
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.,Institute for Evolution and Biodiversity, Westfälische Wilhelms University, Münster, Germany
| | - A Séguret
- Institute for Evolution and Biodiversity, Westfälische Wilhelms University, Münster, Germany
| | - D A Grasso
- Department of Chemistry, Life Sciences and Environmental Sustainability, Università di Parma, Parma, Italy
| | - E Bornberg-Bauer
- Institute for Evolution and Biodiversity, Westfälische Wilhelms University, Münster, Germany
| | - S Foitzik
- Institute of Molecular and Organismic Evolution, Johannes Gutenberg University, Mainz, Germany
| | - J Heinze
- Zoology / Evolutionary Biology, University of Regensburg, Regensburg, Germany
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13
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Duncan EJ, Cunningham CB, Dearden PK. Phenotypic Plasticity: What Has DNA Methylation Got to Do with It? INSECTS 2022; 13:110. [PMID: 35206684 PMCID: PMC8878681 DOI: 10.3390/insects13020110] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 12/14/2022]
Abstract
How does one genome give rise to multiple, often markedly different, phenotypes in response to an environmental cue? This phenomenon, known as phenotypic plasticity, is common amongst plants and animals, but arguably the most striking examples are seen in insects. Well-known insect examples include seasonal morphs of butterfly wing patterns, sexual and asexual reproduction in aphids, and queen and worker castes of eusocial insects. Ultimately, we need to understand how phenotypic plasticity works at a mechanistic level; how do environmental signals alter gene expression, and how are changes in gene expression translated into novel morphology, physiology and behaviour? Understanding how plasticity works is of major interest in evolutionary-developmental biology and may have implications for understanding how insects respond to global change. It has been proposed that epigenetic mechanisms, specifically DNA methylation, are the key link between environmental cues and changes in gene expression. Here, we review the available evidence on the function of DNA methylation of insects, the possible role(s) for DNA methylation in phenotypic plasticity and also highlight key outstanding questions in this field as well as new experimental approaches to address these questions.
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Affiliation(s)
- Elizabeth J. Duncan
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | | | - Peter K. Dearden
- Genomics Aotearoa and Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
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14
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Morandin C, Brendel VP. Tools and applications for integrative analysis of DNA methylation in social insects. Mol Ecol Resour 2021; 22:1656-1674. [PMID: 34861105 DOI: 10.1111/1755-0998.13566] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 12/15/2022]
Abstract
DNA methylation is a common epigenetic signalling tool and an important biological process which is widely studied in a large array of species. The presence, level and function of DNA methylation vary greatly across species. In some insects, DNA methylation systems are minimal, and overall methylation rates tend to be low in all studied insect species. Low methylation levels probed by whole-genome bisulphite sequencing require great care with respect to data quality control and interpretation. Here, we introduce BWASP/R, a complete workflow that allows efficient, scalable and entirely reproducible analyses of raw DNA methylation sequencing data. Consistent application of quality control filters and analysis parameters provides fair comparisons among different studies and an integrated view of all experiments on one species. We describe the capabilities of the BWASP/R workflow by re-analysing several publicly available social insect WGBS data sets, comprising 70 samples and cumulatively 147 replicates from four different species. We show that the CpG methylome comprises only about 1.5% of CpG sites in the honeybee genome and that the cumulative data are consistent with genetic signatures of site accessibility and physiological control of methylation levels.
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Affiliation(s)
- Claire Morandin
- Department of Ecology and Evolution, Biophore, University of Lausanne, Lausanne, Switzerland
| | - Volker P Brendel
- Departments of Biology and Computer Science, Indiana University, Bloomingto, Indiana, USA
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15
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Olivares-Castro G, Cáceres-Jensen L, Guerrero-Bosagna C, Villagra C. Insect Epigenetic Mechanisms Facing Anthropogenic-Derived Contamination, an Overview. INSECTS 2021; 12:780. [PMID: 34564220 PMCID: PMC8468710 DOI: 10.3390/insects12090780] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 12/14/2022]
Abstract
Currently, the human species has been recognized as the primary species responsible for Earth's biodiversity decline. Contamination by different chemical compounds, such as pesticides, is among the main causes of population decreases and species extinction. Insects are key for ecosystem maintenance; unfortunately, their populations are being drastically affected by human-derived disturbances. Pesticides, applied in agricultural and urban environments, are capable of polluting soil and water sources, reaching non-target organisms (native and introduced). Pesticides alter insect's development, physiology, and inheritance. Recently, a link between pesticide effects on insects and their epigenetic molecular mechanisms (EMMs) has been demonstrated. EMMs are capable of regulating gene expression without modifying genetic sequences, resulting in the expression of different stress responses as well as compensatory mechanisms. In this work, we review the main anthropogenic contaminants capable of affecting insect biology and of triggering EMMs. EMMs are involved in the development of several diseases in native insects affected by pesticides (e.g., anomalous teratogenic reactions). Additionally, EMMs also may allow for the survival of some species (mainly pests) under contamination-derived habitats; this may lead to biodiversity decline and further biotic homogenization. We illustrate these patterns by reviewing the effect of neonicotinoid insecticides, insect EMMs, and their ecological consequences.
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Affiliation(s)
- Gabriela Olivares-Castro
- Instituto de Entomología, Universidad Metropolitana de Ciencias de la Educación, Avenida José Pedro Alessandri 774, Santiago 7760197, Chile;
| | - Lizethly Cáceres-Jensen
- Laboratorio de Físicoquímica Analítica, Departamento de Química, Facultad de Ciencias Básicas, Universidad Metropolitana de Ciencias de la Educación, Santiago 7760197, Chile;
| | - Carlos Guerrero-Bosagna
- Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden;
- Environmental Toxicology Program, Department of Integrative Biology, Uppsala University, 752 36 Uppsala, Sweden
| | - Cristian Villagra
- Instituto de Entomología, Universidad Metropolitana de Ciencias de la Educación, Avenida José Pedro Alessandri 774, Santiago 7760197, Chile;
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16
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Kausar S, Abbas MN, Cui H. A review on the DNA methyltransferase family of insects: Aspect and prospects. Int J Biol Macromol 2021; 186:289-302. [PMID: 34237376 DOI: 10.1016/j.ijbiomac.2021.06.205] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/22/2021] [Accepted: 06/30/2021] [Indexed: 12/11/2022]
Abstract
The DNA methyltransferase family contains a conserved set of DNA-modifying enzymatic proteins. They are responsible for epigenetic gene modulation, such as transcriptional silencing, transcription activation, and post-transcriptional modulation. Recent research has revealed that the canonical DNA methyltransferases (DNMTs) biological roles go beyond their traditional functions of establishing and maintaining DNA methylation patterns. Although a complete DNA methylation toolkit is absent in most insect orders, recent evidence indicates the de novo DNA methylation and maintenance function remain conserved. Studies using various molecular approaches provided evidence that DNMTs are multi-functional proteins. However, still in-depth studies on their biological role lack due to the least studied area in insects. Here, we review the DNA methylation toolkit of insects, focusing on recent research on various insect orders, which exhibit DNA methylation at different levels, and for which DNMTs functional studies have become available in recent years. We survey research on the potential roles of DNMTs in the regulation of gene transcription in insect species. DNMTs participate in different physiological processes by interacting with other epigenetic factors. Future studies on insect's DNMTs will benefit to understand developmental processes, responses to various stimuli, and adaptability of insects to different environmental conditions.
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Affiliation(s)
- Saima Kausar
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
| | - Muhammad Nadeem Abbas
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
| | - Hongjuan Cui
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China.
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17
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Oldroyd BP, Yagound B. The role of epigenetics, particularly DNA methylation, in the evolution of caste in insect societies. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200115. [PMID: 33866805 PMCID: PMC8059649 DOI: 10.1098/rstb.2020.0115] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2020] [Indexed: 12/14/2022] Open
Abstract
Eusocial insects can be defined as those that live in colonies and have distinct queens and workers. For most species, queens and workers arise from a common genome, and so caste-specific developmental trajectories must arise from epigenetic processes. In this review, we examine the epigenetic mechanisms that may be involved in the regulation of caste dimorphism. Early work on honeybees suggested that DNA methylation plays a causal role in the divergent development of queen and worker castes. This view has now been challenged by studies that did not find consistent associations between methylation and caste in honeybees and other species. Evidence for the involvement of methylation in modulating behaviour of adult workers is also inconsistent. Thus, the functional significance of DNA methylation in social insects remains equivocal. This article is part of the theme issue 'How does epigenetics influence the course of evolution?'
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Affiliation(s)
- Benjamin P. Oldroyd
- BEE Laboratory, School of Life and Environmental Sciences A12, University of Sydney, New South Wales 2006, Australia
- Wissenschaftskolleg zu Berlin, Wallotstrasse 19, 14193 Berlin, Germany
| | - Boris Yagound
- BEE Laboratory, School of Life and Environmental Sciences A12, University of Sydney, New South Wales 2006, Australia
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18
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Sieber KR, Dorman T, Newell N, Yan H. (Epi)Genetic Mechanisms Underlying the Evolutionary Success of Eusocial Insects. INSECTS 2021; 12:498. [PMID: 34071806 PMCID: PMC8229086 DOI: 10.3390/insects12060498] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022]
Abstract
Eusocial insects, such as bees, ants, and wasps of the Hymenoptera and termites of the Blattodea, are able to generate remarkable diversity in morphology and behavior despite being genetically uniform within a colony. Most eusocial insect species display caste structures in which reproductive ability is possessed by a single or a few queens while all other colony members act as workers. However, in some species, caste structure is somewhat plastic, and individuals may switch from one caste or behavioral phenotype to another in response to certain environmental cues. As different castes normally share a common genetic background, it is believed that much of this observed within-colony diversity results from transcriptional differences between individuals. This suggests that epigenetic mechanisms, featured by modified gene expression without changing genes themselves, may play an important role in eusocial insects. Indeed, epigenetic mechanisms such as DNA methylation, histone modifications and non-coding RNAs, have been shown to influence eusocial insects in multiple aspects, along with typical genetic regulation. This review summarizes the most recent findings regarding such mechanisms and their diverse roles in eusocial insects.
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Affiliation(s)
- Kayli R. Sieber
- Department of Biology, University of Florida, Gainesville, FL 32611, USA; (K.R.S.); (T.D.); (N.N.)
| | - Taylor Dorman
- Department of Biology, University of Florida, Gainesville, FL 32611, USA; (K.R.S.); (T.D.); (N.N.)
| | - Nicholas Newell
- Department of Biology, University of Florida, Gainesville, FL 32611, USA; (K.R.S.); (T.D.); (N.N.)
| | - Hua Yan
- Department of Biology, University of Florida, Gainesville, FL 32611, USA; (K.R.S.); (T.D.); (N.N.)
- Center for Smell and Taste, University of Florida, Gainesville, FL 32611, USA
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19
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10-hydroxy-2E-decenoic acid (10HDA) does not promote caste differentiation in Melipona scutellaris stingless bees. Sci Rep 2021; 11:9882. [PMID: 33972627 PMCID: PMC8110752 DOI: 10.1038/s41598-021-89212-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/16/2021] [Indexed: 02/03/2023] Open
Abstract
In bees from genus Melipona, differential feeding is not enough to fully explain female polyphenism. In these bees, there is a hypothesis that in addition to the environmental component (food), a genetic component is also involved in caste differentiation. This mechanism has not yet been fully elucidated and may involve epigenetic and metabolic regulation. Here, we verified that the genes encoding histone deacetylases HDAC1 and HDAC4 and histone acetyltransferase KAT2A were expressed at all stages of Melipona scutellaris, with fluctuations between developmental stages and castes. In larvae, the HDAC genes showed the same profile of Juvenile Hormone titers-previous reported-whereas the HAT gene exhibited the opposite profile. We also investigated the larvae and larval food metabolomes, but we did not identify the putative queen-fate inducing compounds, geraniol and 10-hydroxy-2E-decenoic acid (10HDA). Finally, we demonstrated that the histone deacetylase inhibitor 10HDA-the major lipid component of royal jelly and hence a putative regulator of honeybee caste differentiation-was unable to promote differentiation in queens in Melipona scutellaris. Our results suggest that epigenetic and hormonal regulations may act synergistically to drive caste differentiation in Melipona and that 10HDA is not a caste-differentiation factor in Melipona scutellaris.
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20
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Majoe M, Libbrecht R, Foitzik S, Nehring V. Queen loss increases worker survival in leaf-cutting ants under paraquat-induced oxidative stress. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190735. [PMID: 33678018 PMCID: PMC7938173 DOI: 10.1098/rstb.2019.0735] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2020] [Indexed: 01/18/2023] Open
Abstract
Longevity is traded off with fecundity in most solitary species, but the two traits are positively linked in social insects. In ants, the most fecund individuals (queens and kings) live longer than the non-reproductive individuals, the workers. In many species, workers may become fertile following queen loss, and recent evidence suggests that worker fecundity extends worker lifespan. We postulated that this effect is in part owing to improved resilience to oxidative stress, and tested this hypothesis in three Myrmicine ants: Temnothorax rugatulus, and the leaf-cutting ants Atta colombica and Acromyrmex echinatior. We removed the queen from colonies to induce worker reproduction and subjected workers to oxidative stress. Oxidative stress drastically reduced survival, but this effect was less pronounced in leaf-cutting ant workers from queenless nests. We also found that, irrespective of oxidative stress, outside workers died earlier than inside workers did, likely because they were older. Since At. colombica workers cannot produce fertile offspring, our results indicate that direct reproduction is not necessary to extend the lives of queenless workers. Our findings suggest that workers are less resilient to oxidative stress in the presence of the queen, and raise questions on the proximate and ultimate mechanisms underlying socially mediated variation in worker lifespan. This article is part of the theme issue 'Ageing and sociality: why, when and how does sociality change ageing patterns?'
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Affiliation(s)
- Megha Majoe
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany
- Institute for Biology I (Zoology), University of Freiburg, Hauptstrasse 1, D-79104 Freiburg, Germany
| | - Romain Libbrecht
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany
| | - Volker Nehring
- Institute for Biology I (Zoology), University of Freiburg, Hauptstrasse 1, D-79104 Freiburg, Germany
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21
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Villagra C, Frías-Lasserre D. Epigenetic Molecular Mechanisms in Insects. NEOTROPICAL ENTOMOLOGY 2020; 49:615-642. [PMID: 32514997 DOI: 10.1007/s13744-020-00777-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 04/06/2020] [Indexed: 06/11/2023]
Abstract
Insects are the largest animal group on Earth both in biomass and diversity. Their outstanding success has inspired genetics and developmental research, allowing the discovery of dynamic process explaining extreme phenotypic plasticity and canalization. Epigenetic molecular mechanisms (EMMs) are vital for several housekeeping functions in multicellular organisms, regulating developmental, ontogenetic trajectories and environmental adaptations. In Insecta, EMMs are involved in the development of extreme phenotypic divergences such as polyphenisms and eusocial castes. Here, we review the history of this research field and how the main EMMs found in insects help to understand their biological processes and diversity. EMMs in insects confer them rapid response capacity allowing insect either to change with plastic divergence or to keep constant when facing different stressors or stimuli. EMMs function both at intra as well as transgenerational scales, playing important roles in insect ecology and evolution. We discuss on how EMMs pervasive influences in Insecta require not only the control of gene expression but also the dynamic interplay of EMMs with further regulatory levels, including genetic, physiological, behavioral, and environmental among others, as was earlier proposed by the Probabilistic Epigenesis model and Developmental System Theory.
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Affiliation(s)
- C Villagra
- Instituto de Entomología, Univ Metropolitana de Ciencias de la Educación, Santiago, Chile.
| | - D Frías-Lasserre
- Instituto de Entomología, Univ Metropolitana de Ciencias de la Educación, Santiago, Chile
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22
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Hou L, Wang X, Yang P, Li B, Lin Z, Kang L, Wang X. DNA methyltransferase 3 participates in behavioral phase change in the migratory locust. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 121:103374. [PMID: 32283278 DOI: 10.1016/j.ibmb.2020.103374] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 03/06/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
DNA methylation plays important roles in the behavioral plasticity of animals. The migratory locust, Locusta migratoria, displays striking density-dependent phenotypic plasticity that can reversely transit between solitarious and gregarious phases. However, the role and the mechanism through which DNA methylation is involved in locust phase change remain unknown. Here, we investigated the expression levels of three DNA methyltransferase genes and their roles in the regulation of locust phase changes. All three Dnmt genes, namely, Dnmt1, Dnmt2 and Dnmt3 showed high expression levels in the brains of gregarious locusts. By contrast, only Dnmt3 transcript rapidly responded to population density changes, decreasing during the isolation of gregarious locusts and steadily increasing upon the crowding of solitarious locusts. Dnmt3 knockdown significantly reduced the phase-related locomotor activity, rather than the attraction index, in gregarious and crowded solitarious locusts. Transcriptome analysis showed that Dnmt3 knockdown upregulated the genes related to metabolism and transporting activity and downregulated those associated with oxidative stress response. The expression level of the phase-core transcriptional factor, hormone receptor HR3, was significantly suppressed in the brain after Dnmt3 knockdown. Moreover, there was significant overlap in the differentially expressed genes between Dnmt3 RNAi and HR3 RNAi data sets, suggesting HR3 may act as key transcriptional factor mediating Dnmt3-controlled gene expression profiles in locust brains. These findings suggest that Dnmt3 transcription is involved in locust behavioral transition, implying the possible roles of DNA methylation in phase-related phenotypic plasticity in locusts.
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Affiliation(s)
- Li Hou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuesong Wang
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Pengcheng Yang
- Beijing Institutes of Life Science, Chinese Academy of Science, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Beibei Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhe Lin
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Le Kang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China; Beijing Institutes of Life Science, Chinese Academy of Science, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.
| | - Xianhui Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China.
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23
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Friedman DA, Johnson BR, Linksvayer TA. Distributed physiology and the molecular basis of social life in eusocial insects. Horm Behav 2020; 122:104757. [PMID: 32305342 DOI: 10.1016/j.yhbeh.2020.104757] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 03/30/2020] [Accepted: 04/06/2020] [Indexed: 12/24/2022]
Abstract
The traditional focus of physiological and functional genomic research is on molecular processes that play out within a single multicellular organism. In the colonial (eusocial) insects such as ants, bees, and termites, molecular and behavioral responses of interacting nestmates are tightly linked, and key physiological processes are regulated at the scale of the colony. Such colony-level physiological processes regulate nestmate physiology in a distributed fashion, through various social communication mechanisms. As a result of physiological decentralization over evolutionary time, organismal mechanisms, for example related to pheromone detection, hormone signaling, and neural signaling pathways, are deployed in novel contexts to influence nestmate and colony traits. Here we explore how functional genomic, physiological, and behavioral studies can benefit from considering the traits of eusocial insects in this light. We highlight functional genomic work exploring how nestmate-level and colony-level traits arise and are influenced by interactions among physiologically-specialized nestmates of various developmental stages. We also consider similarities and differences between nestmate-level (organismal) and colony-level (superorganismal) physiological processes, and make specific hypotheses regarding the physiology of eusocial taxa. Integrating theoretical models of distributed systems with empirical functional genomics approaches will be useful in addressing fundamental questions related to the evolution of eusociality and collective behavior in natural systems.
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Affiliation(s)
- D A Friedman
- University of California, Davis, Department of Entomology, Davis, CA 95616, United States of America.
| | - B R Johnson
- University of California, Davis, Department of Entomology, Davis, CA 95616, United States of America
| | - T A Linksvayer
- University of Pennsylvania, Department of Biology, Pennsylvania, PA 19104, United States of America
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24
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Libbrecht R, Nadrau D, Foitzik S. A Role of Histone Acetylation in the Regulation of Circadian Rhythm in Ants. iScience 2020; 23:100846. [PMID: 32004990 PMCID: PMC6995257 DOI: 10.1016/j.isci.2020.100846] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 12/03/2019] [Accepted: 01/13/2020] [Indexed: 12/15/2022] Open
Abstract
In many organisms, circadian rhythms and associated oscillations in gene expression are controlled by post-translational modifications of histone proteins. Although epigenetic mechanisms influence key aspects of insect societies, their implication in regulating circadian rhythms has not been studied in social insects. Here we ask whether histone acetylation plays a role in adjusting circadian activity in the ant Temnothorax longispinosus. We characterized activity patterns in 20 colonies to reveal that these ants exhibit a diurnal rhythm in colony-level activity and can rapidly respond to changes in the light regime. Then we fed T. longispinosus colonies with C646, a chemical inhibitor of histone acetyltransferases, to show that treated colonies lost their circadian rhythmicity and failed to adjust their activity to the light regime. These findings suggest a role for histone acetylation in controlling rhythmicity in ants and implicate epigenetic processes in the regulation of circadian rhythms in a social context.
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Affiliation(s)
- Romain Libbrecht
- Institute of Organismic and Molecular Evolution (IOME), Johannes Gutenberg University Mainz, Biozentrum I, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany.
| | - Dennis Nadrau
- Institute of Organismic and Molecular Evolution (IOME), Johannes Gutenberg University Mainz, Biozentrum I, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution (IOME), Johannes Gutenberg University Mainz, Biozentrum I, Hanns Dieter Hüsch Weg 15, 55128 Mainz, Germany
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