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Walton A, Herman JJ, Rueppell O. Social life results in social stress protection: a novel concept to explain individual life-history patterns in social insects. Biol Rev Camb Philos Soc 2024; 99:1444-1457. [PMID: 38468146 DOI: 10.1111/brv.13074] [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: 09/13/2023] [Revised: 02/28/2024] [Accepted: 03/04/2024] [Indexed: 03/13/2024]
Abstract
Resistance to and avoidance of stress slow aging and confer increased longevity in numerous organisms. Honey bees and other superorganismal social insects have two main advantages over solitary species to avoid or resist stress: individuals can directly help each other by resource or information transfer, and they can cooperatively control their environment. These benefits have been recognised in the context of pathogen and parasite stress as the concept of social immunity, which has been extensively studied. However, we argue that social immunity is only a special case of a general concept that we define here as social stress protection to include group-level defences against all biotic and abiotic stressors. We reason that social stress protection may have allowed the evolution of reduced individual-level defences and individual life-history optimization, including the exceptional aging plasticity of many social insects. We describe major categories of stress and how a colonial lifestyle may protect social insects, particularly against temporary peaks of extreme stress. We use the honey bee (Apis mellifera L.) to illustrate how patterns of life expectancy may be explained by social stress protection and how modern beekeeping practices can disrupt social stress protection. We conclude that the broad concept of social stress protection requires rigorous empirical testing because it may have implications for our general understanding of social evolution and specifically for improving honey bee health.
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Affiliation(s)
- Alexander Walton
- Department of Biological Sciences, University of Alberta, CW 405, Biological Sciences Building, Edmonton, Alberta, Canada
| | - Jacob J Herman
- Department of Biological Sciences, University of Alberta, CW 405, Biological Sciences Building, Edmonton, Alberta, Canada
| | - Olav Rueppell
- Department of Biological Sciences, University of Alberta, CW 405, Biological Sciences Building, Edmonton, Alberta, Canada
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2
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Brülhart J, Süß A, Oettler J, Heinze J, Schultner E. Sex- and caste-specific developmental responses to juvenile hormone in an ant with maternal caste determination. J Exp Biol 2024; 227:jeb247396. [PMID: 38779857 DOI: 10.1242/jeb.247396] [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: 01/25/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Juvenile hormone is considered to be a master regulator of polyphenism in social insects. In the ant Cardiocondyla obscurior, whether a female egg develops into a queen or a worker is determined maternally and caste-specific differentiation occurs in embryos, so that queens and workers can be distinguished in a non-invasive manner from late embryogenesis onwards. This ant also exhibits two male morphs - winged and wingless males. Here, we used topical treatment with juvenile hormone III and its synthetic analogue methoprene, a method that influences caste determination and differentiation in some ant species, to investigate whether hormone manipulation affects the development and growth of male, queen- and worker-destined embryos and larvae. We found no effect of hormone treatment on female caste ratios or body sizes in any of the treated stages, even though individuals reacted to heightened hormone availability with increased expression of krüppel-homolog 1, a conserved JH first-response gene. In contrast, hormone treatment resulted in the emergence of significantly larger males, although male morph fate was not affected. These results show that in C. obscurior, maternal caste determination leads to irreversible and highly canalized caste-specific development and growth.
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Affiliation(s)
- Jeanne Brülhart
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Anja Süß
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Jan Oettler
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Jürgen Heinze
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Eva Schultner
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
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3
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Pereira RC, Vieira Júnior JOL, Barcelos JVPL, Peçanha LS, França TA, Mendonça LVP, da Silva WR, Samuels RI, Silva GA. The stingless bee Trigona spinipes (Hymenoptera: Apidae) is at risk from a range of insecticides via direct ingestion and trophallactic exchanges. PEST MANAGEMENT SCIENCE 2024; 80:2188-2198. [PMID: 38158650 DOI: 10.1002/ps.7956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 12/04/2023] [Accepted: 12/30/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND The stingless bee, Trigona spinipes, is an important pollinator of numerous native and cultivated plants. Trigona spinipes populations can be negatively impacted by insecticides commonly used for pest control in crops. However, this species has been neglected in toxicological studies. Here we observed the effects of seven insecticides on the survival of bees that had fed directly on insecticide-contaminated food sources or received insecticides via trophallactic exchanges between nestmates. The effects of insecticides on flight behavior were also determined for the compounds considered to be of low toxicity. RESULTS Imidacloprid, spinosad and malathion were categorized as highly toxic to T. spinipes, whereas lambda-cyhalothrin, methomyl and chlorfenapyr were of medium to low toxicity and interfered with two aspects of flight behavior evaluated here. Chlorantraniliprole was the only insecticide tested here that had no significant effect on T. spinipes survival, although it did interfere with one aspect of flight capacity. A single bee that had ingested malathion, spinosad or imidacloprid, could contaminate three, four and nineteen other bees, respectively via trophallaxis, resulting in the death of the recipients. CONCLUSION This is the first study to evaluate the ecotoxicology of a range of insecticides that not only negatively affected T. spinipes survival, but also interfered with flight capacity, a very important aspect of pollination behavior. The toxicity of the insecticides was observed following direct ingestion and also via trophallactic exchanges between nestmates, highlighting the possibility of lethal effects of these insecticides spreading throughout the colony, reducing the survival of non-foraging individuals. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Renata Cunha Pereira
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - José Olívio Lopes Vieira Júnior
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | | | - Ludimila Simões Peçanha
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - Thalles Alves França
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - Laís Viana Paes Mendonça
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - Wanderson Rosa da Silva
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - Richard Ian Samuels
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
| | - Gerson Adriano Silva
- Laboratory of Entomology and Plant Pathology, Universidade Estadual Norte Fluminense Darcy Ribeiro (UENF), Rio de Janeiro, Brazil
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Xu D, Tong Y, Chen B, Li B, Wang S, Zhang D. The influence of first desaturase subfamily genes on fatty acid synthesis, desiccation tolerance and inter-caste nutrient transfer in the termite Coptotermes formosanus. INSECT MOLECULAR BIOLOGY 2024; 33:55-68. [PMID: 37750189 DOI: 10.1111/imb.12877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
Desaturase enzymes play an essential role in the biosynthesis of unsaturated fatty acids (UFAs). In this study, we identified seven "first desaturase" subfamily genes (Cfor-desatA1, Cfor-desatA2-a, Cfor-desatA2-b, Cfor-desatB-a, Cfor-desatB-b, Cfor-desatD and Cfor-desatE) from the Formosan subterranean termite Coptotermes formosanus. These desaturases were highly expressed in the cuticle and fat body of C. formosanus. Inhibition of either the Cfor-desatA2-a or Cfor-desatA2-b gene resulted in a significant decrease in the contents of fatty acids (C16:0, C18:0, C18:1 and C18:2) in worker castes. Moreover, we observed that inhibition of most of desaturase genes identified in this study had a negative impact on the survival rate and desiccation tolerance of workers. Interestingly, when normal soldiers were reared together with dsCfor-desatA2-b-treated workers, they exhibited higher mortality, suggesting that desaturase had an impact on trophallaxis among C. formosanus castes. Our findings shed light on the novel roles of desaturase family genes in the eusocial termite C. formosanus.
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Affiliation(s)
- Danni Xu
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Yuxin Tong
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
| | - Bosheng Chen
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Baoling Li
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Shengyin Wang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Dayu Zhang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
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5
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Negroni MA, LeBoeuf AC. Social administration of juvenile hormone to larvae increases body size and nutritional needs for pupation. ROYAL SOCIETY OPEN SCIENCE 2023; 10:231471. [PMID: 38126067 PMCID: PMC10731321 DOI: 10.1098/rsos.231471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
Social insects often display extreme variation in body size and morphology within the same colony. In many species, adult morphology is socially regulated by workers during larval development. While larval nutrition may play a role in this regulation, it is often difficult to identify precisely what larvae receive from rearing workers, especially when larvae are fed through social regurgitation. Across insects, juvenile hormone is a major regulator of development. In the ant Camponotus floridanus, this hormone is present in the socially regurgitated fluid of workers. We investigated the role the social transfer of juvenile hormone in the social regulation of development. To do this, we administered an artificial regurgitate to larvae through a newly developed handfeeding method that was or was not supplemented with juvenile hormone. Orally administered juvenile hormone increased the nutritional needs of larvae, allowing them to reach a larger size at pupation. Instead of causing them to grow faster, the juvenile hormone treatment extended larval developmental time, allowing them to accumulate resources over a longer period. Handfeeding ant larvae with juvenile hormone resulted in larger adult workers after metamorphosis, suggesting a role for socially transferred juvenile hormone in the colony-level regulation of worker size over colony maturation.
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Affiliation(s)
- Matteo A. Negroni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland
| | - Adria C. LeBoeuf
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, UK
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6
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Franco M, Fassler R, Goldberg TS, Chole H, Herz Y, Woodard SH, Reichmann D, Bloch G. Substances in the mandibular glands mediate queen effects on larval development and colony organization in an annual bumble bee. Proc Natl Acad Sci U S A 2023; 120:e2302071120. [PMID: 37903277 PMCID: PMC10636365 DOI: 10.1073/pnas.2302071120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 09/06/2023] [Indexed: 11/01/2023] Open
Abstract
Social organization is commonly dynamic, with extreme examples in annual social insects, but little is known about the underlying signals and mechanisms. Bumble bee larvae with close contact to a queen do not differentiate into gynes, pupate at an earlier age, and are commonly smaller than siblings that do not contact a queen. We combined detailed observations, proteomics, microRNA transcriptomics, and gland removal surgery to study the regulation of brood development and division of labor in the annual social bumble bee Bombus terrestris. We found that regurgitates fed to larvae by queens and workers differ in their protein and microRNA composition. The proteome of the regurgitate overlaps significantly with that of the mandibular (MG) and hypopharyngeal glands (HPG), suggesting that these exocrine glands are sources of regurgitate proteins. The proteome of the MG and HPG, but not the salivary glands, differs between queens and workers, with caste-specificity preserved for the MG and regurgitate proteomes. Queens subjected to surgical removal of the MG showed normal behavior, brood care, and weight gain, but failed to shorten larval development. These findings suggest that substances in the queen MG are fed to larvae and influence their developmental program. We suggest that when workers emerge and contribute to larval feeding, they dilute the effects of the queen substances, until she can no longer manipulate the development of all larvae. Longer developmental duration may allow female larvae to differentiate into gynes rather than to workers, mediating the colony transition from the ergonomic to the reproductive phase.
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Affiliation(s)
- Maayan Franco
- Department of Ecology, Evolution and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Rosi Fassler
- Department of Biological Chemistry, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Tzvi S. Goldberg
- Department of Ecology, Evolution and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Hanna Chole
- Department of Ecology, Evolution and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Yogev Herz
- Department of Ecology, Evolution and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
- The Federmann Center for the Study of Rationality, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - S. Hollis Woodard
- Department of Entomology, University of California, Riverside, CA92521
| | - Dana Reichmann
- Department of Biological Chemistry, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
- The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Guy Bloch
- Department of Ecology, Evolution and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
- The Federmann Center for the Study of Rationality, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
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7
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Negroni MA, LeBoeuf AC. Metabolic division of labor in social insects. CURRENT OPINION IN INSECT SCIENCE 2023; 59:101085. [PMID: 37454732 DOI: 10.1016/j.cois.2023.101085] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Social insects are known for reproductive and behavioral division of labor, but little attention has been paid to metabolic forms of division of labor. Metabolic division of labor is the partitioning of complementary metabolic tasks between individuals, and it is widespread in social insects. We define two forms of metabolic division of labor, homosynergetic and heterosynergetic, we pinpoint trophallaxis, trophic eggs, and cannibalism as the primary transfers underlying the homosynergetic form and discuss their evolution. We argue that homosynergetic metabolic division of labor underpins fundamental aspects of colony physiology and may be a necessary feature of superorganismal systems, impacting many life history traits. Investigating metabolic division of labor is necessary to understand major evolutionary transition(s) to superorganismality in social insects.
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Affiliation(s)
- Matteo A Negroni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
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8
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Will I, Attardo GM, de Bekker C. Multiomic interpretation of fungus-infected ant metabolomes during manipulated summit disease. Sci Rep 2023; 13:14363. [PMID: 37658067 PMCID: PMC10474057 DOI: 10.1038/s41598-023-40065-0] [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: 05/10/2023] [Accepted: 08/03/2023] [Indexed: 09/03/2023] Open
Abstract
Camponotus floridanus ants show altered behaviors followed by a fatal summiting phenotype when infected with manipulating Ophiocordyceps camponoti-floridani fungi. Host summiting as a strategy to increase transmission is also observed with parasite taxa beyond fungi, including aquatic and terrestrial helminths and baculoviruses. The drastic phenotypic changes can sometimes reflect significant molecular changes in gene expression and metabolite concentrations measured in manipulated hosts. Nevertheless, the underlying mechanisms still need to be fully characterized. To investigate the small molecules producing summiting behavior, we infected C. floridanus ants with O. camponoti-floridani and sampled their heads for LC-MS/MS when we observed the characteristic summiting phenotype. We link this metabolomic data with our previous genomic and transcriptomic data to propose mechanisms that underlie manipulated summiting behavior in "zombie ants." This "multiomic" evidence points toward the dysregulation of neurotransmitter levels and neuronal signaling. We propose that these processes are altered during infection and manipulation based on (1) differential expression of neurotransmitter synthesis and receptor genes, (2) altered abundance of metabolites and neurotransmitters (or their precursors) with known behavioral effects in ants and other insects, and (3) possible suppression of a connected immunity pathway. We additionally report signals for metabolic activity during manipulation related to primary metabolism, detoxification, and anti-stress protectants. Taken together, these findings suggest that host manipulation is likely a multi-faceted phenomenon, with key processes changing at multiple levels of molecular organization.
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Affiliation(s)
- I Will
- Biology Department, University of Central Florida, Orlando, USA.
| | - G M Attardo
- Entomology and Nematology Department, University of California-Davis, Davis, USA
| | - C de Bekker
- Biology Department, University of Central Florida, Orlando, USA.
- Biology Department, Utrecht University, Utrecht, The Netherlands.
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9
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Doi I, Deng W, Ikegami T. Spontaneous and information-induced bursting activities in honeybee hives. Sci Rep 2023; 13:11015. [PMID: 37419944 PMCID: PMC10329038 DOI: 10.1038/s41598-023-37785-8] [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: 09/30/2022] [Accepted: 06/27/2023] [Indexed: 07/09/2023] Open
Abstract
Social entrainment is important for functioning of beehive organization. By analyzing a dataset of approximately 1000 honeybees (Apis mellifera) tracked in 5 trials, we discovered that honeybees exhibit synchronized activity (bursting behavior) in their locomotion. These bursts occurred spontaneously, potentially as a result of intrinsic bee interactions. The empirical data and simulations demonstrate that physical contact is one of the mechanisms for these bursts. We found that a subset of honeybees within a hive which become active before the peak of each burst, and we refer to these bees as "pioneer bees." Pioneer bees are not selected randomly, but rather, are linked to foraging behavior and waggle dancing, which may help spread external information in the hive. By using transfer entropy, we found that information flows from pioneer bees to non-pioneer bees, which suggest that the bursting behavior is caused by foraging behavior and spreading the information through the hive and promoting integrated group behavior among individuals.
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Affiliation(s)
- Itsuki Doi
- Graduate School of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
| | - Weibing Deng
- Key Laboratory of Quark and Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan, 430079, China
| | - Takashi Ikegami
- Graduate School of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
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10
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Kohlmeier P, Feldmeyer B, Foitzik S. Histone acetyltransferases and external demands influence task switching in Temnothorax ants. Biol Lett 2023; 19:20230176. [PMID: 37403711 PMCID: PMC10320658 DOI: 10.1098/rsbl.2023.0176] [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: 04/18/2023] [Accepted: 06/06/2023] [Indexed: 07/06/2023] Open
Abstract
In social hymenopterans, workers specialize in different tasks. Whether a worker nurses the brood or forages is influenced by the responsiveness for task-related cues which in turn is determined by gene expression. Task choice is dynamic and changes throughout a worker's life, e.g. with age or in response to increased demands for certain tasks. Behavioural switches require the ability to adjust gene expression but the mechanisms regulating such transcriptional adaptations remain elusive. We investigated the role of histone acetylation in task specialization and behavioural flexibility in Temnothorax longispinosus ants. By inhibiting p300/CBP histone acetyltransferases (HAT) and manipulating colony composition, we found that HAT inhibition impairs the ability of older workers to switch to brood care. Yet, HAT inhibition increased the ability of young workers to accelerate their behavioural development and switch to foraging. Our data suggest that HAT in combination with social signals indicating task demands play an important role in modulating behaviour. Elevated HAT activity may contribute to keeping young brood carers from leaving the nest, where they would be exposed to high mortality. These findings shed light on the epigenetic processes underlying behavioural flexibility in animals and provide insight into the mechanisms of task specialization in social insects.
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Affiliation(s)
- Philip Kohlmeier
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Germany
- Department of Biological Sciences, University of Memphis, Tennessee, TN, USA
| | - Barbara Feldmeyer
- Molecular Ecology, Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Frankfurt, Germany
| | - Susanne Foitzik
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Germany
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11
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da Silva RC, do Nascimento FS, Wenseleers T, Oi CA. Chemical signatures of egg maternity and Dufour's gland in Vespine wasps. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 2023; 110:25. [PMID: 37227507 DOI: 10.1007/s00114-023-01852-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 05/12/2023] [Accepted: 05/15/2023] [Indexed: 05/26/2023]
Abstract
Cuticular hydrocarbons (CHCs) are often used in the chemical communication among social insects. CHCs can be used in nestmate recognition and as queen pheromones, the latter allows the regulation of the reproductive division of labor. In the common wasp Vespula vulgaris, CHCs and egg-marking hydrocarbons are caste-specific, being hydrocarbon queen pheromones and egg maternity signals. Whether these compounds are conserved among other Vespinae wasps remains unknown. Queens, virgin queens, reproductive workers, and workers belonging to four different wasp species, Dolichovespula media, Dolichovespula saxonica, Vespa crabro, and Vespula germanica, were collected and studied. The cuticular hydrocarbons, egg surface, and Dufour's gland composition were characterized and it was found that chemical compounds are caste-specific in the four species. Quantitative and qualitative differences were detected in the cuticle, eggs, and Dufour's gland. Some specific hydrocarbons that were shown to be overproduced in the cuticle of queens were also present in higher quantities in queen-laid eggs and in their Dufour's gland. These hydrocarbons can be indicated as putative fertility signals that regulate the division of reproductive labor in these Vespine societies. Our results are in line with the literature for V. vulgaris and D. saxonica, in which hydrocarbons were shown to be conserved queen signals. This work presents correlative evidence that queen chemical compounds are found not only over the body surface of females but also in other sources, such as the Dufour's gland and eggs.
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Affiliation(s)
- Rafael Carvalho da Silva
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo - USP, Avenida Bandeirantes, 3900 - Vila Monte Alegre, Ribeirão Preto, SP, 14040-900, Brazil.
| | - Fabio Santos do Nascimento
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo - USP, Avenida Bandeirantes, 3900 - Vila Monte Alegre, Ribeirão Preto, SP, 14040-900, Brazil
| | - Tom Wenseleers
- Laboratory of Socioecology and Social Evolution, KU Leuven - University of Leuven, Leuven, Belgium
| | - Cintia Akemi Oi
- Laboratory of Socioecology and Social Evolution, KU Leuven - University of Leuven, Leuven, Belgium
- Department of Genetics, Evolution and Environment, University College London, London, UK
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12
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Automated monitoring of honey bees with barcodes and artificial intelligence reveals two distinct social networks from a single affiliative behavior. Sci Rep 2023; 13:1541. [PMID: 36707534 PMCID: PMC9883485 DOI: 10.1038/s41598-022-26825-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/20/2022] [Indexed: 01/28/2023] Open
Abstract
Barcode-based tracking of individuals is revolutionizing animal behavior studies, but further progress hinges on whether in addition to determining an individual's location, specific behaviors can be identified and monitored. We achieve this goal using information from the barcodes to identify tightly bounded image regions that potentially show the behavior of interest. These image regions are then analyzed with convolutional neural networks to verify that the behavior occurred. When applied to a challenging test case, detecting social liquid transfer (trophallaxis) in the honey bee hive, this approach yielded a 67% higher sensitivity and an 11% lower error rate than the best detector for honey bee trophallaxis so far. We were furthermore able to automatically detect whether a bee donates or receives liquid, which previously required manual observations. By applying our trophallaxis detector to recordings from three honey bee colonies and performing simulations, we discovered that liquid exchanges among bees generate two distinct social networks with different transmission capabilities. Finally, we demonstrate that our approach generalizes to detecting other specific behaviors. We envision that its broad application will enable automatic, high-resolution behavioral studies that address a broad range of previously intractable questions in evolutionary biology, ethology, neuroscience, and molecular biology.
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13
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Chen J, Du Y. Fire ants feed their nestmates with their own venom. JOURNAL OF INSECT PHYSIOLOGY 2022; 142:104437. [PMID: 35970221 DOI: 10.1016/j.jinsphys.2022.104437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
Venom secretion is widely used by ants for disease control and more generally as an external surface disinfectant. Here we report evidence that Solenopsis invicta feed their nestmates with their own venom. Venom alkaloids were found in crops and midguts of ants at concentration levels that have previously been reported as effective against various pathogens. These venom alkaloids were found in midguts of the larvae, indicating that trophallaxis must be involved in the transfer of venom, since larvae do not produce alkaloids and they depend on workers to be fed. After the mating flight, the female alates shed their wings, burrow into the soil, and start new colonies. The new queen provided alkaloids to her first batch of larvae in the new colony. Since the crops of female alates contain venom alkaloids donated from their nestmate workers, the transfer of worker alkaloids to new generation occurred. After minim adult workers emerged, they took the role in providing venom to the larvae in the colony. Minim adult workers eventually died out and the normal workers became the venom donors in the colony. Although other functions may be possible, considering the well-known antimicrobial property of venom alkaloids and their detected concentration levels, venom in the digestive system is most likely used as an internal antibiotic by fire ants.
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Affiliation(s)
- Jian Chen
- USDA-ARS, Biological Control of Pests Research Unit, Stoneville, MS 38776, USA.
| | - Yuzhe Du
- USDA-ARS, Southern Insect Management Research Unit, Stoneville, MS 38776, USA
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14
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Van den Brande S, Gijbels M, Wynant N, Peeters P, Gansemans Y, Van Nieuwerburgh F, Santos D, Vanden Broeck J. Identification and profiling of stable microRNAs in hemolymph of young and old Locusta migratoria fifth instars. CURRENT RESEARCH IN INSECT SCIENCE 2022; 2:100041. [PMID: 36003267 PMCID: PMC9387440 DOI: 10.1016/j.cris.2022.100041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 06/08/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
Since the discovery of the first microRNA (miRNA) in the nematode Caenorhabditis elegans, numerous novel miRNAs have been identified which can regulate presumably every biological process in a wide range of metazoan species. In accordance, several insect miRNAs have been identified and functionally characterized. While regulatory RNA pathways are traditionally described at an intracellular level, studies reporting on the presence and potential role of extracellular (small) sRNAs have been emerging in the last decade, mainly in mammalian systems. Interestingly, evidence in several species indicates the functional transfer of extracellular RNAs between donor and recipient cells, illustrating RNA-based intercellular communication. In insects, however, reports on extracellular small RNAs are emerging but the number of detailed studies is still very limited. Here, we demonstrate the presence of stable sRNAs in the hemolymph of the migratory locust, Locusta migratoria. Moreover, the levels of several extracellular miRNAs (ex-miRNAs) present in locust hemolymph differed significantly between young and old fifth nymphal instars. In addition, we performed a 'proof of principle' experiment which suggested that extracellularly delivered miRNA molecules are capable of affecting the locusts' development.
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Affiliation(s)
- Stijn Van den Brande
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
| | - Marijke Gijbels
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
| | - Niels Wynant
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
| | - Paulien Peeters
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
| | - Yannick Gansemans
- Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Filip Van Nieuwerburgh
- Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Dulce Santos
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
| | - Jozef Vanden Broeck
- Research group of Molecular Developmental Physiology and Signal Transduction, KU Leuven, Zoological Institute, Naamsestraat 59 box 2465, 3000 Leuven, Belgium
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15
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Traniello IM, Hamilton AR, Gernat T, Cash-Ahmed AC, Harwood GP, Ray AM, Glavin A, Torres J, Goldenfeld N, Robinson GE. Context-dependent influence of threat on honey bee social network dynamics and brain gene expression. J Exp Biol 2022; 225:jeb243738. [PMID: 35202460 PMCID: PMC9001921 DOI: 10.1242/jeb.243738] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/17/2022] [Indexed: 11/20/2022]
Abstract
Adverse social experience affects social structure by modifying the behavior of individuals, but the relationship between an individual's behavioral state and its response to adversity is poorly understood. We leveraged naturally occurring division of labor in honey bees and studied the biological embedding of environmental threat using laboratory assays and automated behavioral tracking of whole colonies. Guard bees showed low intrinsic levels of sociability compared with foragers and nurse bees, but large increases in sociability following exposure to a threat. Threat experience also modified the expression of caregiving-related genes in a brain region called the mushroom bodies. These results demonstrate that the biological embedding of environmental experience depends on an individual's societal role and, in turn, affects its future sociability.
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Affiliation(s)
- Ian M. Traniello
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Adam R. Hamilton
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Tim Gernat
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Swarm Intelligence and Complex Systems Group, Department of Computer Science, Leipzig University, Liepzig D-04109, Germany
| | - Amy C. Cash-Ahmed
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Gyan P. Harwood
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Allyson M. Ray
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Abigail Glavin
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jacob Torres
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Nigel Goldenfeld
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Gene E. Robinson
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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16
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Das B, de Bekker C. Time-course RNASeq of Camponotus floridanus forager and nurse ant brains indicate links between plasticity in the biological clock and behavioral division of labor. BMC Genomics 2022; 23:57. [PMID: 35033027 PMCID: PMC8760764 DOI: 10.1186/s12864-021-08282-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 12/24/2021] [Indexed: 12/19/2022] Open
Abstract
Background Circadian clocks allow organisms to anticipate daily fluctuations in their environment by driving rhythms in physiology and behavior. Inter-organismal differences in daily rhythms, called chronotypes, exist and can shift with age. In ants, age, caste-related behavior and chronotype appear to be linked. Brood-tending nurse ants are usually younger individuals and show “around-the-clock” activity. With age or in the absence of brood, nurses transition into foraging ants that show daily rhythms in activity. Ants can adaptively shift between these behavioral castes and caste-associated chronotypes depending on social context. We investigated how changes in daily gene expression could be contributing to such behavioral plasticity in Camponotus floridanus carpenter ants by combining time-course behavioral assays and RNA-Sequencing of forager and nurse brains. Results We found that nurse brains have three times fewer 24 h oscillating genes than foragers. However, several hundred genes that oscillated every 24 h in forager brains showed robust 8 h oscillations in nurses, including the core clock genes Period and Shaggy. These differentially rhythmic genes consisted of several components of the circadian entrainment and output pathway, including genes said to be involved in regulating insect locomotory behavior. We also found that Vitellogenin, known to regulate division of labor in social insects, showed robust 24 h oscillations in nurse brains but not in foragers. Finally, we found significant overlap between genes differentially expressed between the two ant castes and genes that show ultradian rhythms in daily expression. Conclusion This study provides a first look at the chronobiological differences in gene expression between forager and nurse ant brains. This endeavor allowed us to identify a putative molecular mechanism underlying plastic timekeeping: several components of the ant circadian clock and its output can seemingly oscillate at different harmonics of the circadian rhythm. We propose that such chronobiological plasticity has evolved to allow for distinct regulatory networks that underlie behavioral castes, while supporting swift caste transitions in response to colony demands. Behavioral division of labor is common among social insects. The links between chronobiological and behavioral plasticity that we found in C. floridanus, thus, likely represent a more general phenomenon that warrants further investigation. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-08282-x.
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Affiliation(s)
- Biplabendu Das
- Department of Biology, College of Sciences, University of Central Florida, Orlando, FL, 32816, USA. .,Genomics and Bioinformatics Cluster, University of Central Florida, Orlando, FL, 32816, USA.
| | - Charissa de Bekker
- Department of Biology, College of Sciences, University of Central Florida, Orlando, FL, 32816, USA. .,Genomics and Bioinformatics Cluster, University of Central Florida, Orlando, FL, 32816, USA.
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17
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The pupal moulting fluid has evolved social functions in ants. Nature 2022; 612:488-494. [PMID: 36450990 PMCID: PMC9750870 DOI: 10.1038/s41586-022-05480-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 10/25/2022] [Indexed: 12/02/2022]
Abstract
Insect societies are tightly integrated, complex biological systems in which group-level properties arise from the interactions between individuals1-4. However, these interactions have not been studied systematically and therefore remain incompletely known. Here, using a reverse engineering approach, we reveal that unlike solitary insects, ant pupae extrude a secretion derived from the moulting fluid that is rich in nutrients, hormones and neuroactive substances. This secretion elicits parental care behaviour and is rapidly removed and consumed by the adults. This behaviour is crucial for pupal survival; if the secretion is not removed, pupae develop fungal infections and die. Analogous to mammalian milk, the secretion is also an important source of early larval nutrition, and young larvae exhibit stunted growth and decreased survival without access to the fluid. We show that this derived social function of the moulting fluid generalizes across the ants. This secretion thus forms the basis of a central and hitherto overlooked interaction network in ant societies, and constitutes a rare example of how a conserved developmental process can be co-opted to provide the mechanistic basis of social interactions. These results implicate moulting fluids in having a major role in the evolution of ant eusociality.
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18
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Quque M, Villette C, Criscuolo F, Sueur C, Bertile F, Heintz D. Eusociality is linked to caste-specific differences in metabolism, immune system, and somatic maintenance-related processes in an ant species. Cell Mol Life Sci 2021; 79:29. [PMID: 34971425 PMCID: PMC11073003 DOI: 10.1007/s00018-021-04024-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 10/08/2021] [Accepted: 11/05/2021] [Indexed: 01/08/2023]
Abstract
The social organization of many primate, bird and rodent species and the role of individuals within that organization are associated with specific individual physiological traits. However, this association is perhaps most pronounced in eusocial insects (e.g., termites, ants). In such species, genetically close individuals show significant differences in behavior, physiology, and life expectancy. Studies addressing the metabolic changes according to the social role are still lacking. We aimed at understanding how sociality could influence essential molecular processes in a eusocial insect, the black garden ant (Lasius niger) where queens can live up to ten times longer than workers. Using mass spectrometry-based analysis, we explored the whole metabolome of queens, nest-workers and foraging workers. A former proteomics study done in the same species allowed us to compare the findings of both approaches. Confirming the former results at the proteome level, we showed that queens had fewer metabolites related to immunity. Contrary to our predictions, we did not find any metabolite linked to reproduction in queens. Among the workers, foragers had a metabolic signature reflecting a more stressful environment and a more highly stimulated immune system. We also found that nest-workers had more digestion-related metabolites. Hence, we showed that specific metabolic signatures match specific social roles. Besides, we identified metabolites differently expressed among behavioral castes and involved in nutrient sensing and longevity pathways (e.g., sirtuins, FOXO). The links between such molecular pathways and aging being found in an increasing number of taxa, our results confirm and strengthen their potential universality.
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Affiliation(s)
- Martin Quque
- Université de Strasbourg, CNRS, IPHC UMR 7178, 23 rue du Loess, F-67000, Strasbourg, France.
| | - Claire Villette
- Plant Imaging and Mass Spectrometry (PIMS), Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67000, Strasbourg, France
| | - François Criscuolo
- Université de Strasbourg, CNRS, IPHC UMR 7178, 23 rue du Loess, F-67000, Strasbourg, France
| | - Cédric Sueur
- Université de Strasbourg, CNRS, IPHC UMR 7178, 23 rue du Loess, F-67000, Strasbourg, France
- Institut Universitaire de France, 75005, Paris, France
| | - Fabrice Bertile
- Université de Strasbourg, CNRS, IPHC UMR 7178, 23 rue du Loess, F-67000, Strasbourg, France
- Infrastructure Nationale de Protéomique ProFI, FR2048, Strasbourg, France
| | - Dimitri Heintz
- Plant Imaging and Mass Spectrometry (PIMS), Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67000, Strasbourg, France
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19
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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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20
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Casillas-Pérez B, Pull CD, Naiser F, Naderlinger E, Matas J, Cremer S. Early queen infection shapes developmental dynamics and induces long-term disease protection in incipient ant colonies. Ecol Lett 2021; 25:89-100. [PMID: 34725912 PMCID: PMC9298059 DOI: 10.1111/ele.13907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/04/2021] [Accepted: 10/04/2021] [Indexed: 11/30/2022]
Abstract
Infections early in life can have enduring effects on an organism's development and immunity. In this study, we show that this equally applies to developing 'superorganisms'--incipient social insect colonies. When we exposed newly mated Lasius niger ant queens to a low pathogen dose, their colonies grew more slowly than controls before winter, but reached similar sizes afterwards. Independent of exposure, queen hibernation survival improved when the ratio of pupae to workers was small. Queens that reared fewer pupae before worker emergence exhibited lower pathogen levels, indicating that high brood rearing efforts interfere with the ability of the queen's immune system to suppress pathogen proliferation. Early-life queen pathogen exposure also improved the immunocompetence of her worker offspring, as demonstrated by challenging the workers to the same pathogen a year later. Transgenerational transfer of the queen's pathogen experience to her workforce can hence durably reduce the disease susceptibility of the whole superorganism.
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Affiliation(s)
| | - Christopher D Pull
- IST Austria (Institute of Science and Technology Austria), Klosterneuburg, Austria
| | - Filip Naiser
- Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University in Prague, Czech Republic
| | | | - Jiri Matas
- Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University in Prague, Czech Republic
| | - Sylvia Cremer
- IST Austria (Institute of Science and Technology Austria), Klosterneuburg, Austria
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21
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Trinh T, Ouellette R, de Bekker C. Getting lost: the fungal hijacking of ant foraging behaviour in space and time. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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22
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Sprenger PP, Gerbes LJ, Sahm J, Menzel F. Cuticular hydrocarbon profiles differ between ant body parts: implications for communication and our understanding of CHC diffusion. Curr Zool 2021; 67:531-540. [PMID: 34616951 PMCID: PMC8489164 DOI: 10.1093/cz/zoab012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 02/06/2021] [Indexed: 11/26/2022] Open
Abstract
Insect cuticular hydrocarbons (CHCs) serve as communication signals and protect against desiccation. They form complex blends of up to 150 different compounds. Due to differences in molecular packing, CHC classes differ in melting point. Communication is especially important in social insects like ants, which use CHCs to communicate within the colony and to recognize nestmates. Nestmate recognition models often assume a homogenous colony odor, where CHCs are collected, mixed, and redistributed in the postpharyngeal gland (PPG). Via diffusion, recognition cues should evenly spread over the body surface. Hence, CHC composition should be similar across body parts and in the PPG. To test this, we compared CHC composition among whole-body extracts, PPG, legs, thorax, and gaster, across 17 ant species from 3 genera. Quantitative CHC composition differed between body parts, with consistent patterns across species and CHC classes. Early-melting CHC classes were most abundant in the PPG. In contrast, whole body, gaster, thorax, and legs had increasing proportions of CHC classes with higher melting points. Intraindividual CHC variation was highest for rather solid, late-melting CHC classes, suggesting that CHCs differ in their diffusion rates across the body surface. Our results show that body parts strongly differ in CHC composition, either being rich in rather solid, late-melting, or rather liquid, early-melting CHCs. This implies that recognition cues are not homogenously present across the insect body. However, the unequal diffusion of different CHCs represents a biophysical mechanism that enables caste differences despite continuous CHC exchange among colony members.
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Affiliation(s)
- Philipp P Sprenger
- Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 15, Mainz, 55128, Germany
| | - Lisa J Gerbes
- Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 15, Mainz, 55128, Germany
| | - Jacqueline Sahm
- Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 15, Mainz, 55128, Germany.,Department of Evolutionary Animal Ecology, University of Bayreuth, Universitätsstraße 30, Bayreuth, 95477, Germany
| | - Florian Menzel
- Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 15, Mainz, 55128, Germany
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23
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Honorio R, Jacquier L, Doums C, Molet M. Disentangling the roles of social and individual effects on cadmium tolerance in the ant Temnothorax nylanderi. Biol J Linn Soc Lond 2021. [DOI: 10.1093/biolinnean/blab116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Urbanization brings new pressures for individuals. Among them, trace elements, such as cadmium, are important stressors. A recent study highlights a weaker negative effect of cadmium on city colonies relative to their forest counterparts in the ant Temnothorax nylanderi. Here, we aim to test whether the better tolerance of city colonies in this species results from a better ability of workers to rear larvae despite stressful conditions and/or a better ability of larvae to develop properly despite stressful conditions. We performed a cross-fostering experiment of workers and larvae from city and forest colonies, in common garden conditions in the laboratory. Colonies were fed using cadmium-enriched or cadmium-free food for 2 months, and we measured four life-history traits. As expected, cadmium had a negative impact on all traits. Unexpectedly, we did not observe a better tolerance of city colonies to cadmium, contrary to our previous study, which prevented us from disentangling the respective contributions of workers and larvae to cadmium tolerance. Interestingly, forest colonies seemed to be of better quality in our laboratory conditions. Finally, colony size increased adult survival, but only in the absence of cadmium, suggesting that social buffering could collapse with strong external disturbances.
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Affiliation(s)
- Romain Honorio
- Sorbonne Université, Université Paris Est Créteil, Université Paris Diderot, CNRS, INRAE, IRD, Institute of Ecology and Environmental Sciences-Paris, iEES-Paris, F-75005 Paris, France
| | - Lauren Jacquier
- Sorbonne Université, Université Paris Est Créteil, Université Paris Diderot, CNRS, INRAE, IRD, Institute of Ecology and Environmental Sciences-Paris, iEES-Paris, F-75005 Paris, France
| | - Claudie Doums
- Institut de Systématique Évolution Biodiversité, ISYEB, F-75005 Paris, Sorbonne Université, MNHN, CNRS, EPHE-PSL, Université des Antilles, France
- EPHE, PSL University, F-75014 Paris, France
| | - Mathieu Molet
- Sorbonne Université, Université Paris Est Créteil, Université Paris Diderot, CNRS, INRAE, IRD, Institute of Ecology and Environmental Sciences-Paris, iEES-Paris, F-75005 Paris, France
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24
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Quque M, Bles O, Bénard A, Héraud A, Meunier B, Criscuolo F, Deneubourg JL, Sueur C. Hierarchical networks of food exchange in the black garden ant Lasius niger. INSECT SCIENCE 2021; 28:825-838. [PMID: 32306510 DOI: 10.1111/1744-7917.12792] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
In most eusocial insects, the division of labor results in relatively few individuals foraging for the entire colony. Thus, the survival of the colony depends on its efficiency in meeting the nutritional needs of all its members. Here, we characterize the network topology of a eusocial insect to understand the role and centrality of each caste in this network during the process of food dissemination. We constructed trophallaxis networks from 34 food-exchange experiments in black garden ants (Lasius niger). We tested the influence of brood and colony size on (i) global indices at the network level (i.e., efficiency, resilience, centralization, and modularity) and (ii) individual values (i.e., degree, strength, betweenness, and the clustering coefficient). Network resilience, the ratio between global efficiency and centralization, was stable with colony size but increased in the presence of broods, presumably in response to the nutritional needs of larvae. Individual metrics highlighted the major role of foragers in food dissemination. In addition, a hierarchical clustering analysis suggested that some domestics acted as intermediaries between foragers and other domestics. Networks appeared to be hierarchical rather than random or centralized exclusively around foragers. Finally, our results suggested that networks emerging from social insect interactions can improve group performance and thus colony fitness.
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Affiliation(s)
- Martin Quque
- CNRS, IPHC, Université de Strasbourg, Strasbourg, UMR718, France
| | - Olivier Bles
- Centre for Nonlinear Phenomena and Complex Systems (Cenoli)-CP 231, Université libre de Bruxelles (ULB), Bruxelles, Belgium
| | | | - Amélie Héraud
- CNRS, IPHC, Université de Strasbourg, Strasbourg, UMR718, France
| | | | | | - Jean-Louis Deneubourg
- Centre for Nonlinear Phenomena and Complex Systems (Cenoli)-CP 231, Université libre de Bruxelles (ULB), Bruxelles, Belgium
| | - Cédric Sueur
- CNRS, IPHC, Université de Strasbourg, Strasbourg, UMR718, France
- Institut Universitaire de France, Paris, France
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25
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Santos D, Remans S, Van den Brande S, Vanden Broeck J. RNAs on the Go: Extracellular Transfer in Insects with Promising Prospects for Pest Management. PLANTS (BASEL, SWITZERLAND) 2021; 10:484. [PMID: 33806650 PMCID: PMC8001424 DOI: 10.3390/plants10030484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/28/2021] [Accepted: 03/01/2021] [Indexed: 01/16/2023]
Abstract
RNA-mediated pathways form an important regulatory layer of myriad biological processes. In the last decade, the potential of RNA molecules to contribute to the control of agricultural pests has not been disregarded, specifically via the RNA interference (RNAi) mechanism. In fact, several proofs-of-concept have been made in this scope. Furthermore, a novel research field regarding extracellular RNAs and RNA-based intercellular/interorganismal communication is booming. In this article, we review key discoveries concerning extracellular RNAs in insects, insect RNA-based cell-to-cell communication, and plant-insect transfer of RNA. In addition, we overview the molecular mechanisms implicated in this form of communication and discuss future biotechnological prospects, namely from the insect pest-control perspective.
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Affiliation(s)
- Dulce Santos
- Research Group of Molecular Developmental Physiology and Signal Transduction, Division of Animal Physiology and Neurobiology, Department of Biology, KU Leuven, Naamsestraat 59, 3000 Leuven, Belgium; (S.R.); (S.V.d.B.); (J.V.B.)
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26
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Lowe WH, Martin TE, Skelly DK, Woods HA. Metamorphosis in an Era of Increasing Climate Variability. Trends Ecol Evol 2021; 36:360-375. [PMID: 33414021 DOI: 10.1016/j.tree.2020.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/20/2020] [Accepted: 11/30/2020] [Indexed: 12/11/2022]
Abstract
Most animals have complex life cycles including metamorphosis or other discrete life stage transitions, during which individuals may be particularly vulnerable to environmental stressors. With climate change, individuals will be exposed to increasing thermal and hydrologic variability during metamorphosis, which may affect survival and performance through physiological, behavioral, and ecological mechanisms. Furthermore, because metamorphosis entails changes in traits and vital rates, it is likely to play an important role in how populations respond to increasing climate variability. To identify mechanisms underlying population responses and associated trait and life history evolution, we need new approaches to estimating changes in individual traits and performance throughout metamorphosis, and we need to integrate metamorphosis as an explicit life stage in analytical models.
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Affiliation(s)
- Winsor H Lowe
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
| | - Thomas E Martin
- US Geological Survey, Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT 59812, USA
| | - David K Skelly
- School of the Environment, Yale University, New Haven, CT 06520, USA
| | - H Arthur Woods
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
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27
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English S, Barreaux AMG. The evolution of sensitive periods in development: insights from insects. Curr Opin Behav Sci 2020. [DOI: 10.1016/j.cobeha.2020.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Tragust S, Herrmann C, Häfner J, Braasch R, Tilgen C, Hoock M, Milidakis MA, Gross R, Feldhaar H. Formicine ants swallow their highly acidic poison for gut microbial selection and control. eLife 2020; 9:e60287. [PMID: 33138912 PMCID: PMC7609056 DOI: 10.7554/elife.60287] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/14/2020] [Indexed: 12/23/2022] Open
Abstract
Animals continuously encounter microorganisms that are essential for health or cause disease. They are thus challenged to control harmful microbes while allowing the acquisition of beneficial microbes. This challenge is likely especially important for social insects with respect to microbes in food, as they often store food and exchange food among colony members. Here we show that formicine ants actively swallow their antimicrobial, highly acidic poison gland secretion. The ensuing acidic environment in the stomach, the crop, can limit the establishment of pathogenic and opportunistic microbes ingested with food and improve the survival of ants when faced with pathogen contaminated food. At the same time, crop acidity selectively allows acquisition and colonization by Acetobacteraceae, known bacterial gut associates of formicine ants. This suggests that swallowing of the poison in formicine ants acts as a microbial filter and that antimicrobials have a potentially widespread but so far underappreciated dual role in host-microbe interactions.
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Affiliation(s)
- Simon Tragust
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Claudia Herrmann
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Jane Häfner
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Ronja Braasch
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Christina Tilgen
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Maria Hoock
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Margarita Artemis Milidakis
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
| | - Roy Gross
- Microbiology, Biocenter, University of Würzburg, Am HublandWürzburgGermany
| | - Heike Feldhaar
- Animal Ecology I, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, UniversitätsstraßeBayreuthGermany
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29
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Casadei-Ferreira A, Fischer G, Economo EP. Evidence for a thoracic crop in the workers of some Neotropical Pheidole species (Formicidae: Myrmicinae). ARTHROPOD STRUCTURE & DEVELOPMENT 2020; 59:100977. [PMID: 32818807 DOI: 10.1016/j.asd.2020.100977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/21/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
The ability of ant colonies to transport, store, and distribute food resources through trophallaxis is a key advantage of social life. Nonetheless, how the structure of the digestive system has adapted across the ant phylogeny to facilitate these abilities is still not well understood. The crop and proventriculus, structures in the ant foregut (stomodeum), have received most attention for their roles in trophallaxis. However, potential roles of the esophagus have not been as well studied. Here, we report for the first time the presence of an auxiliary thoracic crop in Pheidole aberrans and Pheidole deima using X-ray micro-computed tomography and 3D segmentation. Additionally, we describe morphological modifications involving the endo- and exoskeleton that are associated with the presence of the thoracic crop. Our results indicate that the presence of a thoracic crop in major workers suggests their potential role as repletes or live food reservoirs, expanding the possibilities of tasks assumed by these individuals in the colony. Our contribution emphasizes the utility of combining data from external and internal morphology to better understand functional and behavioral mechanisms.
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Affiliation(s)
- A Casadei-Ferreira
- Departamento de Zoologia, Universidade Federal do Paraná, Avenida Francisco Heráclito dos Santos, s/n, Centro Politécnico, Curitiba, Mailbox 19020, CEP 81531-980, Brazil.
| | - G Fischer
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Okinawa, 904-0495, Japan.
| | - E P Economo
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Okinawa, 904-0495, Japan.
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30
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Schläppi D, Kettler N, Straub L, Glauser G, Neumann P. Long-term effects of neonicotinoid insecticides on ants. Commun Biol 2020; 3:335. [PMID: 32591582 PMCID: PMC7320190 DOI: 10.1038/s42003-020-1066-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 06/10/2020] [Indexed: 11/25/2022] Open
Abstract
The widespread prophylactic usage of neonicotinoid insecticides has a clear impact on non-target organisms. However, the possible effects of long-term exposure on soil-dwelling organisms are still poorly understood especially for social insects with long-living queens. Here, we show that effects of chronic exposure to the neonicotinoid thiamethoxam on black garden ant colonies, Lasius niger, become visible before the second overwintering. Queens and workers differed in the residue-ratio of thiamethoxam to its metabolite clothianidin, suggesting that queens may have a superior detoxification system. Even though thiamethoxam did not affect queen mortality, neonicotinoid-exposed colonies showed a reduced number of workers and larvae indicating a trade-off between detoxification and fertility. Since colony size is a key for fitness, our data suggest long-term impacts of neonicotinoids on these organisms. This should be accounted for in future environmental and ecological risk assessments of neonicotinoid applications to prevent irreparable damages to ecosystems.
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Affiliation(s)
- Daniel Schläppi
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
| | - Nina Kettler
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Lars Straub
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Agroscope, Swiss Bee Research Centre, Bern, Switzerland
| | - Gaétan Glauser
- Neuchâtel Platform of Analytical Chemistry, University of Neuchâtel, Neuchâtel, Switzerland
| | - Peter Neumann
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Agroscope, Swiss Bee Research Centre, Bern, Switzerland
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31
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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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32
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Wu K, Li S, Wang J, Ni Y, Huang W, Liu Q, Ling E. Peptide Hormones in the Insect Midgut. Front Physiol 2020; 11:191. [PMID: 32194442 PMCID: PMC7066369 DOI: 10.3389/fphys.2020.00191] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/19/2020] [Indexed: 12/20/2022] Open
Abstract
Insects produce many peptide hormones that play important roles in regulating growth, development, immunity, homeostasis, stress, and other processes to maintain normal life. As part of the digestive system, the insect midgut is also affected by hormones secreted from the prothoracic gland, corpus allatum, and various neuronal cells; these hormones regulate the secretion and activity of insects’ digestive enzymes and change their feeding behaviors. In addition, the insect midgut produces certain hormones when it recognizes various components or pathogenic bacteria in ingested foods; concurrently, the hormones regulate other tissues and organs. In addition, intestinal symbiotic bacteria can produce hormones that influence insect signaling pathways to promote host growth and development; this interaction is the result of long-term evolution. In this review, the types, functions, and mechanisms of hormones working on the insect midgut, as well as hormones produced therein, are reviewed for future reference in biological pest control.
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Affiliation(s)
- Kai Wu
- College of Life Sciences, Shangrao Normal University, Shangrao, China
| | - Shirong Li
- Key Laboratory of Insect Developmental and Evolutionary Biology, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Jing Wang
- College of Life Sciences, Shangrao Normal University, Shangrao, China
| | - Yuyang Ni
- College of Life Sciences, Shangrao Normal University, Shangrao, China
| | - Wuren Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Qiuning Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.,Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-Agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Wetland, Yancheng Teachers University, Yancheng, China
| | - Erjun Ling
- Key Laboratory of Insect Developmental and Evolutionary Biology, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.,Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
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33
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Hefetz A. The critical role of primer pheromones in maintaining insect sociality. ACTA ACUST UNITED AC 2020; 74:221-231. [PMID: 30920959 DOI: 10.1515/znc-2018-0224] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 03/02/2019] [Indexed: 11/15/2022]
Abstract
Primer pheromones play a pivotal role in the biology and social organization of insect societies. Despite their importance, they have been less studied because of the complexity of the required bioassays and, consequently, only a few of them have been chemically identified to date. The major primer pheromones are that of the queen pheromones that regulate reproductive skew and maintain colony cohesion and function. From a theoretical viewpoint, several features regarding the chemistry of queen pheromones can be predicted. They should be generally nonvolatile in order to avoid saturation of the colony space, which might otherwise hamper their perception because of sensory habituation. Accordingly, they should be actively dispersed throughout the colony by workers. The queen pheromone should also be caste-specific, qualitatively different from any worker pheromone, and preferably multicomponent, to allow unequivocal identification of the queen. The bi-potency of the female larvae in social Hymenoptera to become queen or worker necessitates strict regulation over pheromone production. Indeed, in the honeybee, the biosynthetic pathways as well as the genomic expressions are completely disparate between queens and workers. Future advances in chemical analyses, transcriptomics, proteomics, and metabolomics will enrich our understanding of the chemistry, mechanisms, and crucial role that primer pheromones play in social evolution.
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Affiliation(s)
- Abraham Hefetz
- Tel Aviv University, Department of Zoology, Tel Aviv, Israel.,Ruppin Academic Center, School of Marine Sciences, Michmoret, Israel
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34
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An evolutionary switch from sibling rivalry to sibling cooperation, caused by a sustained loss of parental care. Proc Natl Acad Sci U S A 2020; 117:2544-2550. [PMID: 31964847 PMCID: PMC7007579 DOI: 10.1073/pnas.1911677117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Sibling rivalry is commonplace within animal families, yet offspring can also work together to promote each other's fitness. Here we show that the extent of parental care can determine whether siblings evolve to compete or to cooperate. Our experiments focus on the burying beetle Nicrophorus vespilloides, which naturally provides variable levels of care to its larvae. We evolved replicate populations of burying beetles under two different regimes of parental care: Some populations were allowed to supply posthatching care to their young (Full Care), while others were not (No Care). After 22 generations of experimental evolution, we found that No Care larvae had evolved to be more cooperative, whereas Full Care larvae were more competitive. Greater levels of cooperation among larvae compensated for the fitness costs caused by parental absence, whereas parental care fully compensated for the fitness costs of sibling rivalry. We dissected the evolutionary mechanisms underlying these responses by measuring indirect genetic effects (IGEs) that occur when different sibling social environments induce the expression of more cooperative (or more competitive) behavior in focal larvae. We found that indirect genetic effects create a tipping point in the evolution of larval social behavior. Once the majority of offspring in a brood start to express cooperative (or competitive) behavior, they induce greater levels of cooperation (or competition) in their siblings. The resulting positive feedback loops rapidly lock larvae into evolving greater levels of cooperation in the absence of parental care and greater levels of rivalry when parents provide care.
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35
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Pray-Grant MG, Grant PA. Ant-icipating Change: An Epigenetic Switch in Reprogramming the Social Lives of Ants. Mol Cell 2020; 77:205-206. [PMID: 31951544 DOI: 10.1016/j.molcel.2019.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glastad et al. (2019) describe a role for the neuronal CoREST corepressor and changes in juvenile hormone (JH) and ecdysone signaling during the reprogramming of social behavioral phenotypes in ants that are reflective of a natural mechanism differentiating "Major" and "Minor" worker ants.
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Affiliation(s)
- Marilyn G Pray-Grant
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Patrick A Grant
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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36
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A spatiotemporal analysis of the food dissemination process and the trophallactic network in the ant Lasius niger. Sci Rep 2019; 9:15620. [PMID: 31666541 PMCID: PMC6821819 DOI: 10.1038/s41598-019-52019-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 10/12/2019] [Indexed: 01/25/2023] Open
Abstract
Intranidal food dissemination through trophallactic exchanges is a fundamental issue in social insect colonies but its underlying mechanisms are far from being clear. In light of the division of work, network theory and collective food management we develop a framework to investigate the spatiotemporal dynamics of the trophallactic network in starved Lasius niger ant colonies. Thanks to tracking methods we are able to record spatial locations of the trophallactic interactions in the nest. We highlight quantitative differences between the foragers and non-foragers concerning their contributions, their roles (donor/recipient) and their spatial distributions. Moreover, at the intracaste level, we show interindividual differences in all activities and we characterise their nature. In particular, within each caste, all the individuals have the same probability to start their food exchange activity but their probability to exchange differs after their first trophallactic event. Interestingly, despite the highlighted interindividual differences, the trophallactic network does not differ from a random network.
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37
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Quque M, Benhaim-Delarbre M, Deneubourg JL, Sueur C, Criscuolo F, Bertile F. Division of labour in the black garden ant (Lasius niger) leads to three distinct proteomes. JOURNAL OF INSECT PHYSIOLOGY 2019; 117:103907. [PMID: 31255645 DOI: 10.1016/j.jinsphys.2019.103907] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/26/2019] [Accepted: 06/26/2019] [Indexed: 06/09/2023]
Abstract
Task specialization in social insects leads to striking intra-specific differences in behaviour, morphology, physiology and longevity, but the underlying mechanisms remain not yet fully understood. Adult colonies of black garden ants (Lasius niger) have a single queen fertilized by one or a small number of males. The inter-individual genetic variability is thus relatively low, making it easier to focus on the individual molecular differences linked to the division of labour. Mass spectrometry-based proteomics enabled us to highlight which biological functions create the difference between queens, foragers and nest-workers. The proteome of each caste reflected nicely their social role: e.g., reproduction for queens, pesticide resistance for foragers - that are the most exposed to environmental risk factors - and, interestingly, digestion for nest-workers, thus highlighting proteomic profiles differences even among workers. Furthermore, our exploratory approach suggests energy trade-off mechanisms - in connection with the theory of social immunity - that might explain the difference in longevity between queens and workers. This study brings evidence that proteomics is able to highlight the subtle mechanisms of molecular regulation induced by social organization.
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Affiliation(s)
- Martin Quque
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France.
| | | | - Jean-Louis Deneubourg
- Université Libre de Bruxelles, CPBT, CP231, Av. F. Roosevelt 50, 1050 Bruxelles, Belgium
| | - Cédric Sueur
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - François Criscuolo
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Fabrice Bertile
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
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Greenwald E, Eckmann JP, Feinerman O. Colony entropy-Allocation of goods in ant colonies. PLoS Comput Biol 2019; 15:e1006925. [PMID: 31381557 PMCID: PMC6681937 DOI: 10.1371/journal.pcbi.1006925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 06/20/2019] [Indexed: 12/01/2022] Open
Abstract
Allocation of goods is a key feature in defining the connection between the individual and the collective scale in any society. Both the process by which goods are to be distributed, and the resulting allocation to the members of the society may affect the success of the population as a whole. One of the most striking natural examples of a highly successful cooperative society is the ant colony which often acts as a single superorganism. In particular, each individual within the ant colony has a "communal stomach" which is used to store and share food with the other colony members by mouth to mouth feeding. Sharing food between communal stomachs allows the colony as a whole to get its food requirements and, more so, allows each individual within the colony to reach its nutritional intake target. The vast majority of colony members do not forage independently but obtain their food through secondary interactions in which food is exchanged between individuals. The global effect of this exchange is not well understood. To gain better understanding into this process we used fluorescence imaging to measure how food from a single external source is distributed and mixed within a Camponotus sanctus ant colony. Using entropic measures to quantify food-blending, we show that while collected food flows into all parts of the colony it mixes only partly. We show that mixing is controlled by the ants' interaction rule which implies that only a fraction of the maximal potential is actually transferred. This rule leads to a robust blending process: i.e., neither the exact food volume that is transferred, nor the interaction schedule are essential to generate the global outcome. Finally, we show how the ants' interaction rules may optimize a trade-off between fast dissemination and efficient mixing. Our results regarding the distribution of a single food source provide a baseline for future studies on distributed regulation of multiple food sources in social insect colonies.
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Affiliation(s)
- Efrat Greenwald
- Department of Physics of Complex systems, Weizmann Institute of Science, Rehovot, Israel
| | - Jean-Pierre Eckmann
- Département de Physique Théorique and Section de Mathématiques, University of Geneva, Geneva, Switzerland
| | - Ofer Feinerman
- Department of Physics of Complex systems, Weizmann Institute of Science, Rehovot, Israel
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Wendt S, Strunk KS, Heinze J, Roider A, Czaczkes TJ. Positive and negative incentive contrasts lead to relative value perception in ants. eLife 2019; 8:e45450. [PMID: 31262401 PMCID: PMC6606023 DOI: 10.7554/elife.45450] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/30/2019] [Indexed: 11/30/2022] Open
Abstract
Humans usually assess things not according to their absolute value, but relative to reference points - a main tenant of Prospect Theory. For example, people rate a new salary relative to previous salaries and salaries of their peers, rather than absolute income. We demonstrate a similar effect in an insect: ants expecting to find low-quality food showed higher acceptance of medium-quality food than ants expecting medium quality, and vice versa for high expectations. Further experiments demonstrate that these contrast effects arise from cognitive rather than mere sensory or pre-cognitive perceptual causes. Social information gained inside the nest can also serve as a reference point: the quality of food received from other ants affected the perceived value of food found later. Value judgement is a key element in decision making, and thus relative value perception strongly influences which option is chosen and ultimately how all animals make decisions.
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Affiliation(s)
- Stephanie Wendt
- Animal Comparative Economics Laboratory, Institute of Zoology and Evolutionary BiologyUniversity of RegensburgRegensburgGermany
| | - Kim S Strunk
- School of Business, Economics and Information Systems, Chair of Management, People and InformationUniversity of PassauPassauGermany
| | - Jürgen Heinze
- Institute of Zoology and Evolutionary BiologyUniversity of RegensburgRegensburgGermany
| | - Andreas Roider
- Department of EconomicsUniversity of RegensburgRegensburgGermany
| | - Tomer J Czaczkes
- Animal Comparative Economics Laboratory, Institute of Zoology and Evolutionary BiologyUniversity of RegensburgRegensburgGermany
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40
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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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41
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Krapf P, Hochenegger N, Arthofer W, Schlick-Steiner BC, Steiner FM. Comparing ant behaviour indices for fine-scale analyses. Sci Rep 2019; 9:6856. [PMID: 31048736 PMCID: PMC6497665 DOI: 10.1038/s41598-019-43313-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 04/17/2019] [Indexed: 12/24/2022] Open
Abstract
Animal behaviour often is characterised by standardised assays. In social insects such as ants, behaviour assays are for example used to characterise aggressive and peaceful behaviour. Such assays differ in the number of individuals, the duration and place of assays, and the scoring scales. Also the behaviour indices used to summarise the results differ. Here, we compared five behaviour indices (Aggression Index, Mean Maximum Aggression Index; and the newly introduced Mean Maximum Peace Index, Mean Behaviour Index aggressive, and Mean Behaviour Index peaceful) using a scoring scale that comprises peaceful and aggressive behaviour. The indices were applied on eight simulations and three observed data sets. The five indices were correlated but frequently differed in their means. Multiple indices were needed to capture the complete behaviour range. Furthermore, subtle differences in workers' behaviour, that is, differences that go beyond the presence/absence of aggression, were only identified when considering multiple indices. We infer that the indices applied are differently suited for different analyses. Fine-scale analyses of behavioural variation profit from using more than one index. The particular choice of index or indices likely influences the interpretation of behaviour and should be carefully done in the light of study species and research question.
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Affiliation(s)
- Patrick Krapf
- Molecular Ecology Group, Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, 6020, Austria.
| | - Nadine Hochenegger
- Molecular Ecology Group, Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, 6020, Austria
| | - Wolfgang Arthofer
- Molecular Ecology Group, Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, 6020, Austria
| | - Birgit C Schlick-Steiner
- Molecular Ecology Group, Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, 6020, Austria
| | - Florian M Steiner
- Molecular Ecology Group, Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, 6020, Austria
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42
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Maori E, Garbian Y, Kunik V, Mozes-Koch R, Malka O, Kalev H, Sabath N, Sela I, Shafir S. A Transmissible RNA Pathway in Honey Bees. Cell Rep 2019; 27:1949-1959.e6. [PMID: 31056439 DOI: 10.1016/j.celrep.2019.04.073] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 12/17/2018] [Accepted: 04/16/2019] [Indexed: 01/06/2023] Open
Abstract
Systemic RNAi, initiated by double-stranded RNA (dsRNA) ingestion, has been reported in diverse invertebrates, including honey bees, demonstrating environmental RNA uptake that undermines homologous gene expression. However, the question why any organism would take up RNA from the environment has remained largely unanswered. Here, we report on horizontal RNA flow among honey bees mediated by secretion and ingestion of worker and royal jelly diets. We demonstrate that transmission of jelly-secreted dsRNA to larvae is biologically active and triggers gene knockdown that lasts into adulthood. Worker and royal jellies harbor differential naturally occurring RNA populations. Jelly RNAs corresponded to honey bee protein-coding genes, transposable elements, and non-coding RNA, as well as bacteria, fungi, and viruses. These results reveal an inherent property of honey bees to share RNA among individuals and generations. Our findings suggest a transmissible RNA pathway, playing a role in social immunity and signaling between members of the hive.
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Affiliation(s)
- Eyal Maori
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK.
| | - Yael Garbian
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
| | - Vered Kunik
- Bioinformatics Consulting, 12 Hailanot Street, Gat-Rimon 4992000, Israel
| | - Rita Mozes-Koch
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
| | - Osnat Malka
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
| | - Haim Kalev
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
| | - Niv Sabath
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Ilan Sela
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
| | - Sharoni Shafir
- The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Rehovot 7610001, Israel
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43
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Warner MR, Mikheyev AS, Linksvayer TA. Transcriptomic basis and evolution of the ant nurse-larval social interactome. PLoS Genet 2019; 15:e1008156. [PMID: 31107868 DOI: 10.1101/514356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 05/31/2019] [Accepted: 04/24/2019] [Indexed: 05/20/2023] Open
Abstract
Development is often strongly regulated by interactions among close relatives, but the underlying molecular mechanisms are largely unknown. In eusocial insects, interactions between caregiving worker nurses and larvae regulate larval development and resultant adult phenotypes. Here, we begin to characterize the social interactome regulating ant larval development by collecting and sequencing the transcriptomes of interacting nurses and larvae across time. We find that the majority of nurse and larval transcriptomes exhibit parallel expression dynamics across larval development. We leverage this widespread nurse-larva gene co-expression to infer putative social gene regulatory networks acting between nurses and larvae. Genes with the strongest inferred social effects tend to be peripheral elements of within-tissue regulatory networks and are often known to encode secreted proteins. This includes interesting candidates such as the nurse-expressed giant-lens, which may influence larval epidermal growth factor signaling, a pathway known to influence various aspects of insect development. Finally, we find that genes with the strongest signatures of social regulation tend to experience relaxed selective constraint and are evolutionarily young. Overall, our study provides a first glimpse into the molecular and evolutionary features of the social mechanisms that regulate all aspects of social life.
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Affiliation(s)
- Michael R Warner
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Alexander S Mikheyev
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology, Onna, Okinawa, Japan
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Timothy A Linksvayer
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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Warner MR, Mikheyev AS, Linksvayer TA. Transcriptomic basis and evolution of the ant nurse-larval social interactome. PLoS Genet 2019; 15:e1008156. [PMID: 31107868 PMCID: PMC6544314 DOI: 10.1371/journal.pgen.1008156] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 05/31/2019] [Accepted: 04/24/2019] [Indexed: 12/13/2022] Open
Abstract
Development is often strongly regulated by interactions among close relatives, but the underlying molecular mechanisms are largely unknown. In eusocial insects, interactions between caregiving worker nurses and larvae regulate larval development and resultant adult phenotypes. Here, we begin to characterize the social interactome regulating ant larval development by collecting and sequencing the transcriptomes of interacting nurses and larvae across time. We find that the majority of nurse and larval transcriptomes exhibit parallel expression dynamics across larval development. We leverage this widespread nurse-larva gene co-expression to infer putative social gene regulatory networks acting between nurses and larvae. Genes with the strongest inferred social effects tend to be peripheral elements of within-tissue regulatory networks and are often known to encode secreted proteins. This includes interesting candidates such as the nurse-expressed giant-lens, which may influence larval epidermal growth factor signaling, a pathway known to influence various aspects of insect development. Finally, we find that genes with the strongest signatures of social regulation tend to experience relaxed selective constraint and are evolutionarily young. Overall, our study provides a first glimpse into the molecular and evolutionary features of the social mechanisms that regulate all aspects of social life.
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Affiliation(s)
- Michael R. Warner
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Alexander S. Mikheyev
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology, Onna, Okinawa, Japan
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Timothy A. Linksvayer
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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45
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I’Anson Price R, Dulex N, Vial N, Vincent C, Grüter C. Honeybees forage more successfully without the "dance language" in challenging environments. SCIENCE ADVANCES 2019; 5:eaat0450. [PMID: 30788430 PMCID: PMC6374110 DOI: 10.1126/sciadv.aat0450] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 01/04/2019] [Indexed: 06/09/2023]
Abstract
Honeybees use the waggle dance to share information about food-site locations with nestmates. However, the importance of this behavior in colony foraging success remains unclear. We tested whether spatial dance information affects colony foraging success in a human-modified temperate environment by comparing colonies with oriented and disoriented dances. Notably, colonies with disoriented dances had greater foraging success. Over time, bees exposed to disoriented dances showed reduced interest in dancing nestmates. This may explain why disoriented colonies had a higher foraging rate than oriented colonies, as bees did not waste time waiting for information. This change in information-use strategy suggests bees learn about the value of dance information. An agent-based model confirmed that, under challenging conditions, waiting for dance information reduces colony foraging success compared to foraging without social information. Our results raise the possibility that humans have created environments to which the waggle dance language is not well adapted.
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Affiliation(s)
- R. I’Anson Price
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - N. Dulex
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - N. Vial
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - C. Vincent
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - C. Grüter
- Institute of Organismic and Molecular Evolution, University of Mainz, Mainz, Germany
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46
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Molecular evolution of juvenile hormone esterase-like proteins in a socially exchanged fluid. Sci Rep 2018; 8:17830. [PMID: 30546082 PMCID: PMC6293014 DOI: 10.1038/s41598-018-36048-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 11/12/2018] [Indexed: 11/08/2022] Open
Abstract
Socially exchanged fluids are a direct means by which an organism can influence conspecifics. It was recently shown that when workers of the carpenter ant Camponotus floridanus feed larval offspring via trophallaxis, they transfer Juvenile Hormone III (JH), a key developmental regulator, as well as paralogs of JH esterase (JHE), an enzyme that catalyzes the hydrolysis of JH. Here we combine proteomic, phylogenetic and selection analyses to investigate the evolution of this esterase subfamily. We show that Camponotus JHE-like proteins have undergone multiple duplications, experienced positive selection, and changed tissue localization to become abundantly and selectively present in trophallactic fluid. The Camponotus trophallactic esterases have maintained their catalytic triads and contain a number of positively-selected amino acid changes distributed throughout the protein, which possibly reflect an adaptation to the highly acidic trophallactic fluid of formicine ants. To determine whether these esterases might regulate larval development, we fed workers with a JHE-specific pharmacological inhibitor to introduce it into the trophallactic network. This inhibitor increased the likelihood of pupation of the larvae reared by these workers, similar to the influence of food supplementation with JH. Together, these findings suggest that JHE-like proteins have evolved a new role in the inter-individual regulation of larval development in the Camponotus genus.
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47
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Allen ML, Rhoades JH, Sparks ME, Grodowitz MJ. Differential Gene Expression in Red Imported Fire Ant ( Solenopsis invicta) (Hymenoptera: Formicidae) Larval and Pupal Stages. INSECTS 2018; 9:E185. [PMID: 30563147 PMCID: PMC6315859 DOI: 10.3390/insects9040185] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/27/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022]
Abstract
Solenopsis invicta Buren is an invasive ant species that has been introduced to multiple continents. One such area, the southern United States, has a history of multiple control projects using chemical pesticides over varying ranges, often resulting in non-target effects across trophic levels. With the advent of next generation sequencing and RNAi technology, novel investigations and new control methods are possible. A robust genome-guided transcriptome assembly was used to investigate gene expression differences between S. invicta larvae and pupae. These life stages differ in many physiological processes; of special importance is the vital role of S. invicta larvae as the colonies' "communal gut". Differentially expressed transcripts were identified related to many important physiological processes, including digestion, development, cell regulation and hormone signaling. This dataset provides essential developmental knowledge that reveals the dramatic changes in gene expression associated with social insect life stage roles, and can be leveraged using RNAi to develop effective control methods.
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Affiliation(s)
- Margaret L Allen
- USDA-ARS Biological Control of Pests Research Unit, National Biological Control Laboratory, Stoneville, MS 38776, USA.
| | - Joshua H Rhoades
- USDA-ARS Invasive Insect Biocontrol and Behavior Laboratory, Beltsville, MD 20705, USA.
| | - Michael E Sparks
- USDA-ARS Invasive Insect Biocontrol and Behavior Laboratory, Beltsville, MD 20705, USA.
| | - Michael J Grodowitz
- USDA-ARS Biological Control of Pests Research Unit, National Biological Control Laboratory, Stoneville, MS 38776, USA.
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48
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Tasaki E, Matsuura K, Iuchi Y. Hypoxia adaptation in termites: hypoxic conditions enhance survival and reproductive activity in royals. INSECT MOLECULAR BIOLOGY 2018; 27:808-814. [PMID: 29989656 DOI: 10.1111/imb.12519] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Termite royals (queen and king) exhibit extraordinary longevity without sacrificing reproductive performance, unlike most animals, in whom lifespan is generally negatively associated with reproduction. Therefore, the regulatory mechanisms underlying longevity have attracted much attention. Although the ageing process is influenced by environmental factors in many insects during their life cycle, it remains unclear whether any factors have an effect on the extended survival and high reproductive capacity of termite royals. Here, we show that hypoxia, possibly an important environmental factor in the nests, enhances survival and reproductive activity in incipient royals of the subterranean termite Reticulitermes speratus compared with those in control conditions. Quantitative real-time PCR analysis revealed that the expression levels of the vitellogenin gene in queens are maintained to a greater extent under hypoxic conditions than under control conditions. The expression levels of the antioxidant enzyme genes RsCAT1 and RsPHGPX are also significantly promoted by hypoxia in queens and kings respectively. These results suggest that hypoxic exposure can contribute in part to achieving high reproductive output by altering gene expression after founding of colonies in the royals. Our study provides novel insights into the effect of a nest environment on the reproductive characteristics in termite royals.
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Affiliation(s)
- E Tasaki
- Department of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
- Department of Applied Bioresources Chemistry, The United Graduate School of Agriculture, Tottori University, Tottori, Japan
| | - K Matsuura
- Department of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Y Iuchi
- Department of Applied Bioresources Chemistry, The United Graduate School of Agriculture, Tottori University, Tottori, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
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49
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50
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He S, Johnston PR, Kuropka B, Lokatis S, Weise C, Plarre R, Kunte HJ, McMahon DP. Termite soldiers contribute to social immunity by synthesizing potent oral secretions. INSECT MOLECULAR BIOLOGY 2018; 27:564-576. [PMID: 29663551 DOI: 10.1111/imb.12499] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The importance of soldiers to termite society defence has long been recognized, but the contribution of soldiers to other societal functions, such as colony immunity, is less well understood. We explore this issue by examining the role of soldiers in protecting nestmates against pathogen infection. Even though they are unable to engage in grooming behaviour, we find that the presence of soldiers of the Darwin termite, Mastotermes darwiniensis, significantly improves the survival of nestmates following entomopathogenic infection. We also show that the copious exocrine oral secretions produced by Darwin termite soldiers contain a high concentration of proteins involved in digestion, chemical biosynthesis, and immunity. The oral secretions produced by soldiers are sufficient to protect nestmates against infection, and they have potent inhibitory activity against a broad spectrum of microbes. Our findings support the view that soldiers may play an important role in colony immunity, and broaden our understanding of the possible function of soldiers during the origin of soldier-first societies.
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Affiliation(s)
- S He
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - P R Johnston
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin Center for Genomics in Biodiversity Research, Berlin, Germany
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany
| | - B Kuropka
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - S Lokatis
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - C Weise
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - R Plarre
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - H-J Kunte
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - D P McMahon
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
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