1
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Searle PC, Shiozawa DK, Evans RP, Hill JT, Suli A, Stark MR, Belk MC. Heterochronic shift in gene expression leads to ontogenetic morphological divergence between two closely related polyploid species. iScience 2024; 27:109566. [PMID: 38632992 PMCID: PMC11022054 DOI: 10.1016/j.isci.2024.109566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 11/04/2023] [Accepted: 03/22/2024] [Indexed: 04/19/2024] Open
Abstract
Heterochrony-alteration to the rate or timing of development-is an important mechanism of trait differentiation associated with speciation. Heterochrony may explain the morphological divergence between two polyploid species, June sucker (Chasmistes liorus) and Utah sucker (Catostomus ardens). The larvae of both species have terminal mouths; however, as adults, June sucker and Utah sucker develop subterminal and ventral mouths, respectively. We document a difference in the timing of shape development and a corresponding change in the timing of gene expression, suggesting the distinctive mouth morphology in June suckers may result from paedomorphosis. Specifically, adult June suckers exhibit an intermediate mouth morphology between the larval (terminal) and ancestral (ventral) states. Endemic and sympatric Chasmistes/Catostomus pairs in two other lakes also are morphologically divergent, but genetically similar. These species pairs could have resulted from the differential expression of genes and corresponding divergence in trait development. Paedomorphosis may lead to adaptive diversification in Catostomids.
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Affiliation(s)
- Peter C. Searle
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | | | - R. Paul Evans
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84602, USA
| | - Jonathon T. Hill
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Arminda Suli
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Michael R. Stark
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Mark C. Belk
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
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2
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Seistrup AS, Choppin M, Govind S, Feldmeyer B, Kever M, Karaulanov E, Séguret A, Karunanithi S, Almeida MV, Ketting RF, Foitzik S. Age- and caste-independent piRNAs in the germline and miRNA profiles linked to caste and fecundity in the ant Temnothorax rugatulus. Mol Ecol 2023; 32:6027-6043. [PMID: 37830492 DOI: 10.1111/mec.17162] [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: 05/22/2023] [Accepted: 09/26/2023] [Indexed: 10/14/2023]
Abstract
Social insects are models for studies of phenotypic plasticity. Ant queens and workers vary in fecundity and lifespan, which are enhanced and extended in queens. Yet, the regulatory mechanisms underlying this variation are not well understood. Ant queens live and reproduce for years, so that they need to protect their germline from transposable element (TE) activity, which may be redundant in short-lived, often sterile workers. We analysed the expression of two protective classes of small RNAs, microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), in various tissues, castes and age classes of the ant Temnothorax rugatulus. In queens, piRNAs were highly abundant in ovaries with TEs being their clear targets, with reduced but still detectable piRNA-specific ping-pong signatures in thorax and brains. piRNA pathway activity varied little with age in queens. Moreover, the reduced ovaries of workers also exhibited similar piRNA activity and this not only in young, fertile workers, but also in older foragers with regressed ovaries. Therefore, these ants protect their germline through piRNA activity, regardless of ovarian development, age or caste, even in sterile workers often considered the soma of the superorganism. Our tissue-specific miRNA analysis detected the expression of 304 miRNAs, of which 105 were expressed in all tissues, 10 enriched in the brain, three in the thorax, whereas 83 were ovarian-specific. We identified ovarian miRNAs whose expression was related to caste, fecundity and age, and which likely regulate group-specific gene expression. sRNA shifts in young- to middle-aged queens were minor, suggesting delayed senescence in this reproductive caste.
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Affiliation(s)
- Ann-Sophie Seistrup
- Institute of Molecular Biology, Mainz, Germany
- International PhD Programme on Gene Regulation, Epigenetics & Genome Stability, Mainz, Germany
| | - Marina Choppin
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Shamitha Govind
- Institute of Molecular Biology, Mainz, Germany
- International PhD Programme on Gene Regulation, Epigenetics & Genome Stability, Mainz, Germany
| | - Barbara Feldmeyer
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Molecular Ecology, Frankfurt, Germany
| | - Marion Kever
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Alice Séguret
- School of Biological Sciences, University of Bristol, Bristol, UK
| | | | - Miguel V Almeida
- Institute of Molecular Biology, Mainz, Germany
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - René F Ketting
- Institute of Molecular Biology, Mainz, Germany
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Mainz, Germany
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3
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Helanterä H, Ozan M, Sundström L. Relatedness modulates reproductive competition among queens in ant societies with multiple queens. Behav Ecol 2023; 34:340-345. [PMID: 37192926 PMCID: PMC10183207 DOI: 10.1093/beheco/arad004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 10/05/2022] [Accepted: 01/09/2023] [Indexed: 03/03/2023] Open
Abstract
Reproductive sharing in animal groups with multiple breeders, insects and vertebrates alike, contains elements of both conflict and cooperation, and depends on both relatedness between co-breeders, as well as their internal and external conditions. We studied how queens of the ant Formica fusca adjust their reproductive efforts in response to experimental manipulations of the kin competition regime in their nest. Queens respond to the presence of competitors by increasing their egg laying efforts, but only if the competitors are highly fecund and distantly related. Such a mechanism is likely to decrease harmful competition among close relatives. We demonstrate that queens of Formica fusca fine-tune their cooperative breeding behaviors in response to kinship and fecundity of others in a remarkably precise and flexible manner.
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Affiliation(s)
- Heikki Helanterä
- Faculty of Biological and Environmental Sciences, Organismal and Evolutionary Biology Research Programme, P.O.BOX 65, FI 00014, Helsinki University, Finland
- Tvärminne Zoological station, J.A. Palménintie 260, FI 10900 Hanko, Finland
- Faculty of Science, Ecology and Genetics Research Unit, FI 90014, University of Oulu, Finland
| | - Martina Ozan
- Faculty of Biological and Environmental Sciences, Organismal and Evolutionary Biology Research Programme, P.O.BOX 65, FI 00014, Helsinki University, Finland
- Tvärminne Zoological station, J.A. Palménintie 260, FI 10900 Hanko, Finland
| | - Liselotte Sundström
- Faculty of Biological and Environmental Sciences, Organismal and Evolutionary Biology Research Programme, P.O.BOX 65, FI 00014, Helsinki University, Finland
- Tvärminne Zoological station, J.A. Palménintie 260, FI 10900 Hanko, Finland
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4
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Zhang Y, Ma W, Ma C, Zhang Q, Tian Z, Tian Z, Chen H, Guo J, Wan F, Zhou Z. The hsp70 new functions as a regulator of reproduction both female and male in Ophraella communa. Front Mol Biosci 2022; 9:931525. [PMID: 36203880 PMCID: PMC9531545 DOI: 10.3389/fmolb.2022.931525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/30/2022] [Indexed: 11/13/2022] Open
Abstract
Heat shock proteins (Hsps) function as molecular chaperones that enable organisms to withstand stress and maintain normal life activities. In this study, we identified heat shock protein 70 (encoded by hsp70), which exhibits a higher expression in the mature male testis than in the unmature testis of Ophraella communa. Tissue expression profile revealed that Ochsp70 levels in males were highest in the testis, whereas those in females were highest in the head. Moreover, the expression of Ochsp70 was found to be significantly induced in female bursa copulatrix after mating. Double-stranded RNA dsOchsp70 was injected into males to performance RNA interference, which significantly decreased the male Ochsp70 expression levels within 20 d post-injection, whereas no effect was observed on the Ochsp70 expression level in the females after mating with dsOchsp70-injected males. However, significant downregulation of female fertility was marked simultaneously. Furthermore, knockdown of female Ochsp70 expression also led to a significant reduction in fertility. Finally, comparative transcriptomic analysis identified glucose dehydrogenase and insulin-like growth factor binding protein as putative downstream targets of Ochsp70. Overall, we deduced that Ochsp70 is an indispensable gene and a potential male mating factor in O. communa, which regulates reproduction.
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Affiliation(s)
- Yan Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Weihua Ma
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Chao Ma
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qinglu Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhenya Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Institute of Plant Protection, Guangxi Academy of Agricultural Sciences, Nanning, China
| | - Zhenqi Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongsong Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Institute of Plant Protection, Guangxi Academy of Agricultural Sciences, Nanning, China
| | - Jianying Guo
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fanghao Wan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhongshi Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya, China
- *Correspondence: Zhongshi Zhou,
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5
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Jaimes-Nino LM, Heinze J, Oettler J. Late-life fitness gains and reproductive death in Cardiocondyla obscurior ants. eLife 2022; 11:74695. [PMID: 35384839 PMCID: PMC8986319 DOI: 10.7554/elife.74695] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 03/21/2022] [Indexed: 11/13/2022] Open
Abstract
A key hypothesis for the occurrence of senescence is the decrease in selection strength due to the decrease in the proportion of newborns from parents attaining an advanced age - the so-called selection shadow. Strikingly, queens of social insects have long lifespans and reproductive senescence seems to be negligible. By lifelong tracking of 99 Cardiocondyla obscurior (Formicidae: Myrmicinae) ant colonies, we find that queens shift to the production of sexuals in late life regardless of their absolute lifespan or the number of workers present. Furthermore, RNAseq analyses of old queens past their peak of reproductive performance showed the development of massive pathology while queens were still fertile, leading to rapid death. We conclude that the evolution of superorganismality is accompanied by 'continuusparity,' a life history strategy that is distinct from other iteroparous and semelparous strategies across the tree of life, in that it combines continuous reproduction with a fitness peak late in life.
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Affiliation(s)
| | - Jürgen Heinze
- Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | - Jan Oettler
- Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
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6
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Hakala SM, Meurville MP, Stumpe M, LeBoeuf AC. Biomarkers in a socially exchanged /fluid reflect colony maturity, behavior, and distributed metabolism. eLife 2021; 10:74005. [PMID: 34725037 PMCID: PMC8608388 DOI: 10.7554/elife.74005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 10/15/2021] [Indexed: 12/24/2022] Open
Abstract
In cooperative systems exhibiting division of labor, such as microbial communities, multicellular organisms, and social insect colonies, individual units share costs and benefits through both task specialization and exchanged materials. Socially exchanged fluids, like seminal fluid and milk, allow individuals to molecularly influence conspecifics. Many social insects have a social circulatory system, where food and endogenously produced molecules are transferred mouth-to-mouth (stomodeal trophallaxis), connecting all the individuals in the society. To understand how these endogenous molecules relate to colony life, we used quantitative proteomics to investigate the trophallactic fluid within colonies of the carpenter ant Camponotus floridanus. We show that different stages of the colony life cycle circulate different types of proteins: young colonies prioritize direct carbohydrate processing; mature colonies prioritize accumulation and transmission of stored resources. Further, colonies circulate proteins implicated in oxidative stress, ageing, and social insect caste determination, potentially acting as superorganismal hormones. Brood-caring individuals that are also closer to the queen in the social network (nurses) showed higher abundance of oxidative stress-related proteins. Thus, trophallaxis behavior could provide a mechanism for distributed metabolism in social insect societies. The ability to thoroughly analyze the materials exchanged between cooperative units makes social insect colonies useful models to understand the evolution and consequences of metabolic division of labor at other scales. Division of labor is essential for cooperation, because groups can achieve more when individuals specialize in different tasks. This happens across the natural world, from different cells in organisms performing specific roles, to the individuals in an ant colony carrying out diverse duties. In both of these systems, individuals work together to ensure the survival of the collective unit – the body or the colony – instead of competing against each other. One of the main ways division of labor is evident within these two systems is regarding reproduction. Both in the body and in an ant colony, only one or a few individual units can reproduce, while the rest provide support. In the case of ant colonies, only queens and males reproduce, while the young workers nurse the brood and older workers forage for food. This intense cooperation requires close communication between individual units – in the case of some species of ants, by sharing fluids mouth-to-mouth. These fluids contain food but also many molecules produced by the ants themselves, including proteins. Given that both individuals and the colony as a whole change as they age – with workers acquiring new roles, and new queens and males only reared once the colony is mature – it is likely that the proteins transmitted in the fluid also change. To better understand whether the lifecycles of individuals and the age of the colony affect the fluids shared by carpenter ants Camponotus floridanus, Hakala et al. examined the ant-produced proteins in these fluids. This revealed differences in the proteins shared by young and mature colonies, and young nurse ants and older forager ants. In young colonies, the fluids contained proteins involved in fast sugar processing; while in mature colonies, the fluids contained more proteins to store nutrients, which help insect larvae grow into larger individuals, like queens. Young worker ants, who spend their time nursing the brood, produced more anti-aging proteins. This may be because these ants are in close contact with the queen, who lives much longer than the rest of the ants in the colony. Taken together, these observations suggest that ants divide the labor of metabolism, as well as work and reproduction. Dividing the labor of metabolism among individuals is one more similarity between ants and the cells of a multicellular organism, like a fly or a human. Division of labor allows the sharing of burden, with some individuals lightening the load of others. Understanding how ants achieve this by sharing fluids could shed new light on this complex exchange at other scales or in other organisms. By matching proteins to life stages, researchers have a starting point to examine individual molecules in more detail.
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Affiliation(s)
- Sanja M Hakala
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | | | - Michael Stumpe
- Metabolomics and Proteomics Platform, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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7
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Harrison MC, Niño LMJ, Rodrigues MA, Ryll J, Flatt T, Oettler J, Bornberg-Bauer E. Gene Coexpression Network Reveals Highly Conserved, Well-Regulated Anti-Ageing Mechanisms in Old Ant Queens. Genome Biol Evol 2021; 13:6263858. [PMID: 33944936 PMCID: PMC8214412 DOI: 10.1093/gbe/evab093] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2021] [Indexed: 12/11/2022] Open
Abstract
Evolutionary theories of ageing predict a reduction in selection efficiency with age, a so-called “selection shadow,” due to extrinsic mortality decreasing effective population size with age. Classic symptoms of ageing include a deterioration in transcriptional regulation and protein homeostasis. Understanding how ant queens defy the trade-off between fecundity and lifespan remains a major challenge for the evolutionary theory of ageing. It has often been discussed that the low extrinsic mortality of ant queens, that are generally well protected within the nest by workers and soldiers, should reduce the selection shadow acting on old queens. We tested this by comparing strength of selection acting on genes upregulated in young and old queens of the ant, Cardiocondyla obscurior. In support of a reduced selection shadow, we find old-biased genes to be under strong purifying selection. We also analyzed a gene coexpression network (GCN) with the aim to detect signs of ageing in the form of deteriorating regulation and proteostasis. We find no evidence for ageing. In fact, we detect higher connectivity in old queens indicating increased transcriptional regulation with age. Within the GCN, we discover five highly correlated modules that are upregulated with age. These old-biased modules regulate several antiageing mechanisms such as maintenance of proteostasis, transcriptional regulation, and stress response. We observe stronger purifying selection on central hub genes of these old-biased modules compared with young-biased modules. These results indicate a lack of transcriptional ageing in old C. obscurior queens, possibly facilitated by strong selection at old age and well-regulated antiageing mechanisms.
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Affiliation(s)
- Mark C Harrison
- Institute for Evolution and Biodiversity, University of Münster, Germany
| | | | | | - Judith Ryll
- Institute for Evolution and Biodiversity, University of Münster, Germany
| | - Thomas Flatt
- Department of Biology, University of Fribourg, Switzerland
| | - Jan Oettler
- Institut für Zoologie/Evolutionsbiologie, University of Regensburg, Germany
| | - Erich Bornberg-Bauer
- Department of Biology, University of Fribourg, Switzerland.,Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
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8
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Heinze J, Giehr J. The plasticity of lifespan in social insects. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190734. [PMID: 33678025 PMCID: PMC7938164 DOI: 10.1098/rstb.2019.0734] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2020] [Indexed: 01/11/2023] Open
Abstract
One of the central questions of ageing research is why lifespans of organisms differ so tremendously among related taxa and, even more surprising, among members of the same species. Social insects provide a particularly pronounced example for this. Here, we review previously published information on lifespan plasticity in social insects and provide new data on worker lifespan in the ant Cardiocondyla obscurior, which because of its relatively short lifespan is a convenient model to study ageing. We show that individual lifespan may vary within species with several reproductive and social traits, such as egg-laying rate, queen number, task, colony size and colony composition. For example, in Cardiocondyla, highly fecund queens live longer than reproductively less active queens, and workers tend to live longer when transferred into a novel social environment or, as we show with new data, into small colonies. We hypothesize that this plasticity of lifespan serves to maximize the reproductive output of the colony as a whole and thus the inclusive fitness of all individuals. The underlying mechanisms that link the social environment or reproductive status with lifespan are currently unresolved. Several studies in honeybees and ants indicate an involvement of nutrient-sensing pathways, but the details appear to differ among species. 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)
- Jürgen Heinze
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg 93040 Germany
| | - Julia Giehr
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg 93040 Germany
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9
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Negroni MA, Macit MN, Stoldt M, Feldmeyer B, Foitzik S. Molecular regulation of lifespan extension in fertile ant workers. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190736. [PMID: 33678017 DOI: 10.1098/rstb.2019.0736] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The evolution of sociality in insects caused a divergence in lifespan between reproductive and non-reproductive castes. Ant queens can live for decades, while most workers survive only weeks to a few years. In most organisms, longevity is traded-off with reproduction, but in social insects, these two life-history traits are positively linked. Once fertility is induced in workers, e.g. by queen removal, worker lifespan increases. The molecular regulation of this positive link between fecundity and longevity and generally the molecular underpinnings of caste-specific senescence are not well understood. Here, we investigate the transcriptomic regulation of lifespan and reproduction in fat bodies of three worker groups in the ant Temnothorax rugatulus. In a long-term experiment, workers that became fertile in the absence of the queen showed increased survival and upregulation of genes involved in longevity and fecundity pathways. Interestingly, workers that re-joined their queen after months exhibited intermediate ovary development, but retained a high expression of longevity and fecundity genes. Strikingly, the queen's presence causes a general downregulation of genes in worker fat bodies. Our findings point to long-term consequences of fertility induction in workers, even after re-joining their queen. Moreover, we reveal longevity genes and pathways modulated during insect social evolution. 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)
- Matteo Antoine Negroni
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Maide Nesibe Macit
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Marah Stoldt
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Barbara Feldmeyer
- Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
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10
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Kennedy A, Herman J, Rueppell O. Reproductive activation in honeybee ( Apis mellifera) workers protects against abiotic and biotic stress. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190737. [PMID: 33678021 DOI: 10.1098/rstb.2019.0737] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Social insect reproductives exhibit exceptional longevity instead of the classic trade-off between somatic maintenance and reproduction. Even normally sterile workers experience a significant increase in life expectancy when they assume a reproductive role. The mechanisms that enable the positive relation between the antagonistic demands of reproduction and somatic maintenance are unclear. To isolate the effect of reproductive activation, honeybee workers were induced to activate their ovaries. These reproductively activated workers were compared to controls for survival and gene expression patterns after exposure to Israeli Acute Paralysis Virus or the oxidative stressor paraquat. Reproductive activation increased survival, indicating better immunity and oxidative stress resistance. After qPCR analysis confirmed our experimental treatments at the physiological level, whole transcriptome analysis revealed that paraquat treatment significantly changed the expression of 1277 genes in the control workers but only two genes in reproductively activated workers, indicating that reproductive activation preemptively protects against oxidative stress. Significant overlap between genes that were upregulated by reproductive activation and in response to paraquat included prominent members of signalling pathways and anti-oxidants known to affect ageing. Thus, while our results confirm a central role of vitellogenin, they also point to other mechanisms to explain the molecular basis of the lack of a cost of reproduction and the exceptional longevity of social insect reproductives. Thus, socially induced reproductive activation preemptively protects honeybee workers against stressors, explaining their longevity. 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)
- Anissa Kennedy
- Department of Biology, University of North Carolina Greensboro, 321 McIver Street, Greensboro, NC 27403, USA
| | - Jacob Herman
- Department of Biology, University of North Carolina Greensboro, 321 McIver Street, Greensboro, NC 27403, USA
| | - Olav Rueppell
- Department of Biology, University of North Carolina Greensboro, 321 McIver Street, Greensboro, NC 27403, USA
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11
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Negroni MA, Feldmeyer B, Foitzik S. Experimental increase in fecundity causes upregulation of fecundity and body maintenance genes in the fat body of ant queens. Biol Lett 2021; 17:20200909. [PMID: 33592155 PMCID: PMC8086957 DOI: 10.1098/rsbl.2020.0909] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 01/25/2021] [Indexed: 02/06/2023] Open
Abstract
In most organisms, fecundity and longevity are negatively associated and the molecular regulation of these two life-history traits is highly interconnected. In addition, nutrient intake often has opposing effects on lifespan and reproduction. In contrast to solitary insects, the main reproductive individual of social hymenopterans, the queen, is also the most long-lived. During development, queen larvae are well-nourished, but we are only beginning to understand the impact of nutrition on the queens' adult life and the molecular regulation and connectivity of fecundity and longevity. Here, we used two experimental manipulations to alter queen fecundity in the ant Temnothorax rugatulus and investigated associated changes in fat body gene expression. Egg removal triggered a fecundity increase, leading to expression changes in genes with functions in fecundity such as oogenesis and body maintenance. Dietary restriction lowered the egg production of queens and altered the expression of genes linked to autophagy, Toll signalling, cellular homeostasis and immunity. Our study reveals that an experimental increase in fecundity causes the co-activation of reproduction and body maintenance mechanisms, shedding light on the molecular regulation of the link between longevity and fecundity in social insects.
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Affiliation(s)
- Matteo Antoine Negroni
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Biozentrum, Hanns Dieter Hüsch Weg 15, D-55128 Mainz, Germany
| | - Barbara Feldmeyer
- Molecular Ecology Group, Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14–16, D-60325 Frankfurt am Main, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Biozentrum, Hanns Dieter Hüsch Weg 15, D-55128 Mainz, Germany
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12
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Long-lived Temnothorax ant queens switch from investment in immunity to antioxidant production with age. Sci Rep 2019; 9:7270. [PMID: 31086243 PMCID: PMC6514213 DOI: 10.1038/s41598-019-43796-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 04/15/2019] [Indexed: 01/09/2023] Open
Abstract
Senescence is manifested by an increase in molecular damage and a deterioration of biological functions with age. In most organisms, body maintenance is traded-off with reproduction. This negative relationship between longevity and fecundity is also evident on the molecular level. Exempt from this negative trait association, social insect queens are both extremely long-lived and highly fecund. Here, we study changes in gene expression with age and fecundity in ant queens to understand the molecular basis of their long lifespan. We analyse tissue-specific gene expression in young founding queens and old fecund queens of the ant Temnothorax rugatulus. More genes altered their expression with age in the fat body than in the brain. Despite strong differences in ovary development, few fecundity genes were differentially expressed. Young founding queens invested in immunity (i.e. activation of Toll signalling pathway) and resistance against environmental and physiological stress (i.e. down-regulation of TOR pathway). Conversely, established older queens invested into anti-aging mechanisms through an overproduction of antioxidants (i.e. upregulation of catalase, superoxide dismutase). Finally, we identified candidate genes and pathways, potentially involved in the association between fertility and longevity in social insects and its proximate basis.
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13
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Monroy Kuhn JM, Meusemann K, Korb J. Long live the queen, the king and the commoner? Transcript expression differences between old and young in the termite Cryptotermes secundus. PLoS One 2019; 14:e0210371. [PMID: 30759161 PMCID: PMC6373952 DOI: 10.1371/journal.pone.0210371] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 12/20/2018] [Indexed: 01/09/2023] Open
Abstract
Social insects provide promising new avenues for aging research. Within a colony, individuals that share the same genetic background can differ in lifespan by up to two orders of magnitude. Reproducing queens (and in termites also kings) can live for more than 20 years, extraordinary lifespans for insects. We studied aging in a termite species, Cryptotermes secundus, which lives in less socially complex societies with a few hundred colony members. Reproductives develop from workers which are totipotent immatures. Comparing transcriptomes of young and old individuals, we found evidence for aging in reproductives that was especially associated with DNA and protein damage and the activity of transposable elements. By contrast, workers seemed to be better protected against aging. Thus our results differed from those obtained for social insects that live in more complex societies. Yet, they are in agreement with lifespan estimates for the study species. Our data are also in line with expectations from evolutionary theory. For individuals that are able to reproduce, it predicts that aging should only start after reaching maturity. As C. secundus workers are immatures with full reproductive options we expect them to invest into anti-aging processes. Our study illustrates that the degree of aging can differ between social insects and that it may be associated with caste-specific opportunities for reproduction.
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Affiliation(s)
- José Manuel Monroy Kuhn
- Evolutionary Biology and Ecology, Albert-Ludwigs-Universität Freiburg, Freiburg, Baden-Württemberg, Germany
- * E-mail: (JMMK); (JK)
| | - Karen Meusemann
- Evolutionary Biology and Ecology, Albert-Ludwigs-Universität Freiburg, Freiburg, Baden-Württemberg, Germany
| | - Judith Korb
- Evolutionary Biology and Ecology, Albert-Ludwigs-Universität Freiburg, Freiburg, Baden-Württemberg, Germany
- * E-mail: (JMMK); (JK)
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14
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Abstract
Between the 1930s and 50s, evolutionary biologists developed a successful theory of why organisms age, firmly rooted in population genetic principles. By the 1980s the evolution of aging had a secure experimental basis. Since the force of selection declines with age, aging evolves due to mutation accumulation or a benefit to fitness early in life. Here we review major insights and challenges that have emerged over the last 35 years: selection does not always necessarily decline with age; higher extrinsic (i.e., environmentally caused) mortality does not always accelerate aging; conserved pathways control aging rate; senescence patterns are more diverse than previously thought; aging is not universal; trade-offs involving lifespan can be 'broken'; aging might be 'druggable'; and human life expectancy continues to rise but compressing late-life morbidity remains a pressing challenge.
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Affiliation(s)
- Thomas Flatt
- Department of Biology, University of Fribourg, Chemin du Musée 10, CH-1700, Fribourg, Switzerland
| | - Linda Partridge
- Max Planck Institute for Biology of Aging, Joseph-Stelzmann-Strasse 9b, D-50931, Cologne, Germany.
- Institute for Healthy Aging and GEE, University College London, Darwin Building, Gower Street, London, WC1E6BT, UK.
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15
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Yaguchi H, Shigenobu S, Hayashi Y, Miyazaki S, Toga K, Masuoka Y, Maekawa K. A lipocalin protein, Neural Lazarillo, is key to social interactions that promote termite soldier differentiation. Proc Biol Sci 2018; 285:rspb.2018.0707. [PMID: 30051867 DOI: 10.1098/rspb.2018.0707] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/05/2018] [Indexed: 12/20/2022] Open
Abstract
Social communication among castes is a crucial component of insect societies. However, the genes involved in soldier determination through the regulation of inter-individual interactions are largely unknown. In an incipient colony of the damp-wood termite Zootermopsis nevadensis, the first larva to develop into a third instar always differentiates into a soldier via frequent trophallactic feeding from the reproductives. Here, by performing RNA-seq analysis of third instar larvae, a homologue of Neural Lazarillo (named ZnNLaz1) was found to be the most differentially expressed gene in these soldier-destined larvae, compared with worker-destined larvae. This gene encodes a lipocalin protein related to the transport of small hydrophobic molecules. RNAi-induced knockdown of ZnNLaz1 significantly inhibited trophallactic interactions with the queen and decreased the soldier differentiation rates. This protein is localized in the gut, particularly in the internal wall, of soldier-destined larvae, suggesting that it is involved in the integration of social signals from the queen through frequent trophallactic behaviours. Based on molecular phylogenetic analysis, we suggest that a novel function of termite NLaz1 has contributed to social evolution from the cockroach ancestors of termites. These results indicated that a high larval NLaz1 expression is crucial for soldier determination through social communication in termites.
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Affiliation(s)
- Hajime Yaguchi
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan.,Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Japan
| | - Shuji Shigenobu
- NIBB Core Research Facilities, National Institute for Basic Biology, Okazaki, Japan
| | | | - Satoshi Miyazaki
- Department of Agri-Production Sciences, Tamagawa University, Machida, Japan
| | - Kouhei Toga
- Department of Biosciences, College of Humanities and Sciences, Nihon University, Tokyo, Japan
| | - Yudai Masuoka
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan.,Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Kiyoto Maekawa
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan
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16
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Elsner D, Meusemann K, Korb J. Longevity and transposon defense, the case of termite reproductives. Proc Natl Acad Sci U S A 2018; 115:5504-5509. [PMID: 29735660 PMCID: PMC6003524 DOI: 10.1073/pnas.1804046115] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Social insects are promising new models in aging research. Within single colonies, longevity differences of several magnitudes exist that can be found elsewhere only between different species. Reproducing queens (and, in termites, also kings) can live for several decades, whereas sterile workers often have a lifespan of a few weeks only. We studied aging in the wild in a highly social insect, the termite Macrotermes bellicosus, which has one of the most pronounced longevity differences between reproductives and workers. We show that gene-expression patterns differed little between young and old reproductives, implying negligible aging. By contrast, old major workers had many genes up-regulated that are related to transposable elements (TEs), which can cause aging. Strikingly, genes from the PIWI-interacting RNA (piRNA) pathway, which are generally known to silence TEs in the germline of multicellular animals, were down-regulated only in old major workers but not in reproductives. Continued up-regulation of the piRNA defense commonly found in the germline of animals can explain the long life of termite reproductives, implying somatic cooption of germline defense during social evolution. This presents a striking germline/soma analogy as envisioned by the superorganism concept: the reproductives and workers of a colony reflect the germline and soma of multicellular animals, respectively. Our results provide support for the disposable soma theory of aging.
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Affiliation(s)
- Daniel Elsner
- Evolutionary Biology & Ecology, University of Freiburg, Freiburg D-79104, Germany
| | - Karen Meusemann
- Evolutionary Biology & Ecology, University of Freiburg, Freiburg D-79104, Germany
| | - Judith Korb
- Evolutionary Biology & Ecology, University of Freiburg, Freiburg D-79104, Germany
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17
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Lawhorn CM, Schomaker R, Rowell JT, Rueppell O. Simple Comparative Analyses of Differentially Expressed Gene Lists May Overestimate Gene Overlap. J Comput Biol 2018; 25:606-612. [PMID: 29658777 DOI: 10.1089/cmb.2017.0262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Comparing the overlap between sets of differentially expressed genes (DEGs) within or between transcriptome studies is regularly used to infer similarities between biological processes. Significant overlap between two sets of DEGs is usually determined by a simple test. The number of potentially overlapping genes is compared to the number of genes that actually occur in both lists, treating every gene as equal. However, gene expression is controlled by transcription factors that bind to a variable number of transcription factor binding sites, leading to variation among genes in general variability of their expression. Neglecting this variability could therefore lead to inflated estimates of significant overlap between DEG lists. With computer simulations, we demonstrate that such biases arise from variation in the control of gene expression. Significant overlap commonly arises between two lists of DEGs that are randomly generated, assuming that the control of gene expression is variable among genes but consistent between corresponding experiments. More overlap is observed when transcription factors are specific to their binding sites and when the number of genes is considerably higher than the number of different transcription factors. In contrast, overlap between two DEG lists is always lower than expected when the genetic architecture of expression is independent between the two experiments. Thus, the current methods for determining significant overlap between DEGs are potentially confounding biologically meaningful overlap with overlap that arises due to variability in control of expression among genes, and more sophisticated approaches are needed.
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Affiliation(s)
- Chelsea M Lawhorn
- 1 Department of Mathematics, Winthrop University , Rock Hill, South Carolina
| | - Rachel Schomaker
- 2 Department of Biology, Florida Southern College , Lakeland, Florida
| | - Jonathan T Rowell
- 3 Department of Mathematics and Statistics, University of North Carolina at Greensboro , Greensboro, North Carolina
| | - Olav Rueppell
- 4 Department of Biology, University of North Carolina at Greensboro , Greensboro, North Carolina
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18
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Blacher P, Huggins TJ, Bourke AFG. Evolution of ageing, costs of reproduction and the fecundity-longevity trade-off in eusocial insects. Proc Biol Sci 2018; 284:rspb.2017.0380. [PMID: 28701554 PMCID: PMC5524490 DOI: 10.1098/rspb.2017.0380] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/07/2017] [Indexed: 01/04/2023] Open
Abstract
Eusocial insects provide special opportunities to elucidate the evolution of ageing as queens have apparently evaded costs of reproduction and reversed the fecundity–longevity trade-off generally observed in non-social organisms. But how reproduction affects longevity in eusocial insects has rarely been tested experimentally. In this study, we took advantage of the reproductive plasticity of workers to test the causal role of reproduction in determining longevity in eusocial insects. Using the eusocial bumblebee Bombus terrestris, we found that, in whole colonies, in which workers could freely ‘choose’ whether to become reproductive, workers' level of ovarian activation was significantly positively associated with longevity and ovary-active workers significantly outlived ovary-inactive workers. By contrast, when reproductivity was experimentally induced in randomly selected workers, thereby decoupling it from other traits, workers' level of ovarian activation was significantly negatively associated with longevity and ovary-active workers were significantly less long-lived than ovary-inactive workers. These findings show that workers experience costs of reproduction and suggest that intrinsically high-quality individuals can overcome these costs. They also raise the possibility that eusocial insect queens exhibit condition-dependent longevity and hence call into question whether eusociality entails a truly reversed fecundity–longevity trade-off involving a fundamental remodelling of conserved genetic and endocrine networks underpinning ageing.
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Affiliation(s)
- Pierre Blacher
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Timothy J Huggins
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Andrew F G Bourke
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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19
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Heinze J. Life-history evolution in ants: the case of Cardiocondyla. Proc Biol Sci 2018; 284:rspb.2016.1406. [PMID: 28298341 DOI: 10.1098/rspb.2016.1406] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/06/2016] [Indexed: 01/09/2023] Open
Abstract
Ants are important components of most terrestrial habitats, and a better knowledge of the diversity of their life histories is essential to understand many aspects of ecosystem functioning. The myrmicine genus Cardiocondyla shows a wide range of colony structures, reproductive behaviours, queen and male lifespans, and habitat use. Reconstructing the evolutionary pathways of individual and social phenotypic traits suggests that the ancestral life history of Cardiocondyla was characterized by the presence of multiple, short-lived queens in small-sized colonies and a male polyphenism with winged dispersers and wingless fighters, which engage in lethal combat over female sexuals within their natal nests. Single queening, queen polyphenism, the loss of winged males and tolerance among wingless males appear to be derived traits that evolved with changes in nesting habits, colony size and the spread from tropical to seasonal environments. The aim of this review is to bring together the information on life-history evolution in Cardiocondyla and to highlight the suitability of this genus for functional genomic studies of adaptation, phenotypic plasticity, senescence, invasiveness and other key life-history traits of ants.
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Affiliation(s)
- Jürgen Heinze
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93040 Regensburg, Germany
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20
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Manfredini F, Romero AE, Pedroso I, Paccanaro A, Sumner S, Brown MJF. Neurogenomic Signatures of Successes and Failures in Life-History Transitions in a Key Insect Pollinator. Genome Biol Evol 2017; 9:3059-3072. [PMID: 29087523 PMCID: PMC5714134 DOI: 10.1093/gbe/evx220] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2017] [Indexed: 12/22/2022] Open
Abstract
Life-history transitions require major reprogramming at the behavioral and physiological level. Mating and reproductive maturation are known to trigger changes in gene transcription in reproductive tissues in a wide range of organisms, but we understand little about the molecular consequences of a failure to mate or become reproductively mature, and it is not clear to what extent these processes trigger neural as well as physiological changes. In this study, we examined the molecular processes underpinning the behavioral changes that accompany the major life-history transitions in a key pollinator, the bumblebee Bombus terrestris. We compared neuro-transcription in queens that succeeded or failed in switching from virgin and immature states, to mated and reproductively mature states. Both successes and failures were associated with distinct molecular profiles, illustrating how development during adulthood triggers distinct molecular profiles within a single caste of a eusocial insect. Failures in both mating and reproductive maturation were explained by a general up-regulation of brain gene transcription. We identified 21 genes that were highly connected in a gene coexpression network analysis: nine genes are involved in neural processes and four are regulators of gene expression. This suggests that negotiating life-history transitions involves significant neural processing and reprogramming, and not just changes in physiology. These findings provide novel insights into basic life-history transitions of an insect. Failure to mate or to become reproductively mature is an overlooked component of variation in natural systems, despite its prevalence in many sexually reproducing organisms, and deserves deeper investigation in the future.
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Affiliation(s)
- Fabio Manfredini
- School of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
- Department of Computer Science, and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, United Kingdom
| | - Alfonso E Romero
- Department of Computer Science, and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, United Kingdom
| | - Inti Pedroso
- Center for Systems Biotechnology, Fraunhofer Chile Research Foundation, Santiago, Chile
| | - Alberto Paccanaro
- Department of Computer Science, and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, United Kingdom
| | - Seirian Sumner
- School of Biological Sciences, University of Bristol, United Kingdom
- Present address: Centre for Biodiversity & Environment Research, Department of Genetics, Evolution & Environment, University College London, London, United Kingdom
| | - Mark J F Brown
- School of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
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21
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The Neuropeptide Corazonin Controls Social Behavior and Caste Identity in Ants. Cell 2017; 170:748-759.e12. [PMID: 28802044 DOI: 10.1016/j.cell.2017.07.014] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 05/23/2017] [Accepted: 07/13/2017] [Indexed: 11/21/2022]
Abstract
Social insects are emerging models to study how gene regulation affects behavior because their colonies comprise individuals with the same genomes but greatly different behavioral repertoires. To investigate the molecular mechanisms that activate distinct behaviors in different castes, we exploit a natural behavioral plasticity in Harpegnathos saltator, where adult workers can transition to a reproductive, queen-like state called gamergate. Analysis of brain transcriptomes during the transition reveals that corazonin, a neuropeptide homologous to the vertebrate gonadotropin-releasing hormone, is downregulated as workers become gamergates. Corazonin is also preferentially expressed in workers and/or foragers from other social insect species. Injection of corazonin in transitioning Harpegnathos individuals suppresses expression of vitellogenin in the brain and stimulates worker-like hunting behaviors, while inhibiting gamergate behaviors, such as dueling and egg deposition. We propose that corazonin is a central regulator of caste identity and behavior in social insects.
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22
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Kohlmeier P, Negroni MA, Kever M, Emmling S, Stypa H, Feldmeyer B, Foitzik S. Intrinsic worker mortality depends on behavioral caste and the queens' presence in a social insect. Naturwissenschaften 2017; 104:34. [PMID: 28353195 DOI: 10.1007/s00114-017-1452-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 02/20/2017] [Accepted: 02/22/2017] [Indexed: 12/30/2022]
Abstract
According to the classic life history theory, selection for longevity depends on age-dependant extrinsic mortality and fecundity. In social insects, the common life history trade-off between fecundity and longevity appears to be reversed, as the most fecund individual, the queen, often exceeds workers in lifespan several fold. But does fecundity directly affect intrinsic mortality also in social insect workers? And what is the effect of task on worker mortality? Here, we studied how social environment and behavioral caste affect intrinsic mortality of ant workers. We compared worker survival between queenless and queenright Temnothorax longispinosus nests and demonstrate that workers survive longer under the queens' absence. Temnothorax ant workers fight over reproduction when the queen is absent and dominant workers lay eggs. Worker fertility might therefore increase lifespan, possibly due to a positive physiological link between fecundity and longevity, or better care for fertile workers. In social insects, division of labor among workers is age-dependant with young workers caring for the brood and old ones going out to forage. We therefore expected nurses to survive longer than foragers, which is what we found. Surprisingly, inactive inside workers showed a lower survival than nurses but comparable to that of foragers. The reduced longevity of inactive workers could be due to them being older than the nurses, or due to a positive effect of activity on lifespan. Overall, our study points to behavioral caste-dependent intrinsic mortality rates and a positive association between fertility and longevity not only in queens but also in ant workers.
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Affiliation(s)
- Philip Kohlmeier
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany.
| | - Matteo Antoine Negroni
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany
| | - Marion Kever
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany
| | - Stefanie Emmling
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany
| | - Heike Stypa
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany
| | - Barbara Feldmeyer
- Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, D-60325, Frankfurt am Main, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Johannes von Müller Weg 6, 55128, Mainz, Germany
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23
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Porcelli D, Westram AM, Pascual M, Gaston KJ, Butlin RK, Snook RR. Gene expression clines reveal local adaptation and associated trade-offs at a continental scale. Sci Rep 2016; 6:32975. [PMID: 27599812 PMCID: PMC5013434 DOI: 10.1038/srep32975] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/18/2016] [Indexed: 01/03/2023] Open
Abstract
Local adaptation, where fitness in one environment comes at a cost in another, should lead to spatial variation in trade-offs between life history traits and may be critical for population persistence. Recent studies have sought genomic signals of local adaptation, but often have been limited to laboratory populations representing two environmentally different locations of a species’ distribution. We measured gene expression, as a proxy for fitness, in males of Drosophila subobscura, occupying a 20° latitudinal and 11 °C thermal range. Uniquely, we sampled six populations and studied both common garden and semi-natural responses to identify signals of local adaptation. We found contrasting patterns of investment: transcripts with expression positively correlated to latitude were enriched for metabolic processes, expressed across all tissues whereas negatively correlated transcripts were enriched for reproductive processes, expressed primarily in testes. When using only the end populations, to compare our results to previous studies, we found that locally adaptive patterns were obscured. While phenotypic trade-offs between metabolic and reproductive functions across widespread species are well-known, our results identify underlying genetic and tissue responses at a continental scale that may be responsible for this. This may contribute to understanding population persistence under environmental change.
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Affiliation(s)
- Damiano Porcelli
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Anja M Westram
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Marta Pascual
- Departament de Genètica, Microbiologia I Estabdistica and IrBio, Universitat de Barcelona, Barcelona 08028, ES
| | - Kevin J Gaston
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, UK
| | - Roger K Butlin
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Rhonda R Snook
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
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24
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Rueppell O, Aumer D, Moritz RF. Ties between ageing plasticity and reproductive physiology in honey bees (Apis mellifera) reveal a positive relation between fecundity and longevity as consequence of advanced social evolution. CURRENT OPINION IN INSECT SCIENCE 2016; 16:64-68. [PMID: 27720052 PMCID: PMC5094365 DOI: 10.1016/j.cois.2016.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 05/05/2016] [Accepted: 05/11/2016] [Indexed: 05/12/2023]
Abstract
Honey bees (Apis mellifera) are the best studied model of ageing among the social insects. As in other social insects, the reproductive queen far outlives her non-reproductive workers despite developing from the same genome in the same colony environment. Thus, the different social roles of the two female castes are critical for the profound phenotypic plasticity. In several special cases, such as the reproductive workers of Apis mellifera capensis, within-caste plasticity enables further studies of the fecundity-longevity syndrome in honey bees. At present, molecular evidence suggests that a reorganization of physiological control pathways may facilitate longevity of reproductive individuals. However, the social role and social environment of the different colony members are also very important and one of the key future questions is how much social facilitation versus internal regulation is responsible for the positive association between fecundity and longevity in honey bees.
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Affiliation(s)
- Olav Rueppell
- University of North Carolina at Greensboro, Department of Biology, Greensboro, NC, USA.
| | - Denise Aumer
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Halle/Saale, Germany
| | - Robin Fa Moritz
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Halle/Saale, Germany
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25
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Feldmeyer B, Mazur J, Beros S, Lerp H, Binder H, Foitzik S. Gene expression patterns underlying parasite-induced alterations in host behaviour and life history. Mol Ecol 2016; 25:648-60. [DOI: 10.1111/mec.13498] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/16/2015] [Accepted: 11/18/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Barbara Feldmeyer
- Evolutionary Biology; Johannes Gutenberg University Mainz; Johannes-von-Müller-Weg 6 55128 Mainz Germany
- Biodiversity and Climate Research Centre; Senckenberg Gesellschaft für Naturforschung; Senckenberganlage 25 60325 Frankfurt Germany
| | - Johanna Mazur
- Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI); University Medical Center Johannes Gutenberg University Mainz; Obere Zahlbacher Str. 69 55131 Mainz Germany
| | - Sara Beros
- Evolutionary Biology; Johannes Gutenberg University Mainz; Johannes-von-Müller-Weg 6 55128 Mainz Germany
| | - Hannes Lerp
- Evolutionary Biology; Johannes Gutenberg University Mainz; Johannes-von-Müller-Weg 6 55128 Mainz Germany
- Natural History Collections; Museum Wiesbaden; Friedrich-Ebert-Allee 2 65185 Wiesbaden Germany
| | - Harald Binder
- Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI); University Medical Center Johannes Gutenberg University Mainz; Obere Zahlbacher Str. 69 55131 Mainz Germany
| | - Susanne Foitzik
- Evolutionary Biology; Johannes Gutenberg University Mainz; Johannes-von-Müller-Weg 6 55128 Mainz Germany
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26
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Rueppell O, Königseder F, Heinze J, Schrempf A. Intrinsic survival advantage of social insect queens depends on reproductive activation. J Evol Biol 2015; 28:2349-54. [PMID: 26348543 PMCID: PMC5540307 DOI: 10.1111/jeb.12749] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/02/2015] [Accepted: 09/02/2015] [Indexed: 01/24/2023]
Abstract
The central trade-off between reproduction and longevity dominates most species' life history. However, no mortality cost of reproduction is apparent in eusocial species, particularly social insects in the order Hymenoptera: one or a few individuals (typically referred to as queens) in a group specialize on reproduction and are generally longer lived than all other group members (typically referred to as workers), despite having the same genome. However, it is unclear whether this survival advantage is due to social facilitation by the group or an intrinsic, individual property. Furthermore, it is unknown whether the correlation between reproduction and longevity is due to a direct mechanistic link or an indirect consequence of the social role of the reproductives. To begin addressing these questions, we performed a comparison of queen and worker longevity in the ant Cardiocondyla obscurior under social isolation conditions. Survival of single queens and workers was compared under laboratory conditions, monitoring and controlling for brood production. Our results indicate that there is no intrinsic survival advantage of queens relative to workers unless individuals are becoming reproductively active. This interactive effect of caste and reproduction on life expectancy outside of the normal social context suggests that the positive correlation between reproduction and longevity in social insect queens is due to a direct link that can activate intrinsic survival mechanisms to ensure queen longevity.
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Affiliation(s)
- Olav Rueppell
- Department of Biology, University of North Carolina, 321 McIver Street., Greensboro, NC 27403, USA
| | - Florian Königseder
- Biologie I, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Jürgen Heinze
- Biologie I, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Alexandra Schrempf
- Biologie I, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
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