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Waring-Sparks AL, Waring-Sparks RA, Darner R, Mortimer NT. Advanced biology students' individual conceptions of scientific researchers after participating in biomedically relevant CRE. JOURNAL OF MICROBIOLOGY & BIOLOGY EDUCATION 2024:e0018323. [PMID: 39189730 DOI: 10.1128/jmbe.00183-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 05/11/2024] [Indexed: 08/28/2024]
Abstract
While undergraduate research has been shown to be a high-impact educational practice, it is logistically impossible for all undergraduate biology majors to have long-term faculty-mentored research experience. Therefore, biology educators and researchers must devise opportunities to engage more students in undergraduate research outside of working directly in their labs. Course-Based Research Experiences (CREs), structured as authentic research experiences, are one such opportunity. In this work, we describe the effects of a CRE with biomedical relevance on students' research skills, attitudes toward science, and perceptions of scientific research and scientific researchers. Results demonstrate that students gained experience in independent research skills including designing their own research project, being accountable for part of a project, and writing a research proposal. Students' perceptions of scientific research and researchers, assessed by the Draw-A-Researcher Task, did not show changes among the whole group, but individual analysis yielded meaningful results related to students' personal changes in how they perceived research and researchers, including their perception of themselves as researchers. This work demonstrates the substantial impact of CREs on upper-level biology undergraduate and graduate students.
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Affiliation(s)
| | | | - Rebekka Darner
- Center for Mathematics, Science, & Technology, Illinois State University, Normal, Illinois, USA
| | - Nathan T Mortimer
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon, USA
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2
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Brantley SE, Stouthamer CM, Kr P, Fischer ML, Hill J, Schlenke TA, Mortimer NT. Host JAK-STAT activity is a target of parasitoid wasp virulence strategies. PLoS Pathog 2024; 20:e1012349. [PMID: 38950076 PMCID: PMC11244843 DOI: 10.1371/journal.ppat.1012349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 07/12/2024] [Accepted: 06/17/2024] [Indexed: 07/03/2024] Open
Abstract
Innate immune responses that allow hosts to survive infection depend on the action of multiple conserved signaling pathways. Pathogens and parasites in turn have evolved virulence factors to target these immune signaling pathways in an attempt to overcome host immunity. Consequently, the interactions between host immune molecules and pathogen virulence factors play an important role in determining the outcome of an infection. The immune responses of Drosophila melanogaster provide a valuable model to understand immune signaling and host-pathogen interactions. Flies are commonly infected by parasitoid wasps and mount a coordinated cellular immune response following infection. This response is characterized by the production of specialized blood cells called lamellocytes that form a tight capsule around wasp eggs in the host hemocoel. The conserved JAK-STAT signaling pathway has been implicated in lamellocyte proliferation and is required for successful encapsulation of wasp eggs. Here we show that activity of Stat92E, the D. melanogaster STAT ortholog, is induced in immune tissues following parasitoid infection. Virulent wasp species are able to suppress Stat92E activity during infection, suggesting they target JAK-STAT pathway activation as a virulence strategy. Furthermore, two wasp species (Leptopilina guineaensis and Ganaspis xanthopoda) suppress phenotypes associated with a gain-of-function mutation in hopscotch, the D. melanogaster JAK ortholog, indicating that they inhibit the activity of the core signaling components of the JAK-STAT pathway. Our data suggest that parasitoid wasp virulence factors block JAK-STAT signaling to overcome fly immune defenses.
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Affiliation(s)
- Susanna E Brantley
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Corinne M Stouthamer
- Department of Entomology, University of Arizona, Tucson, Arizona, United States of America
| | - Pooja Kr
- School of Biological Sciences, Illinois State University, Normal, Illinois, United States of America
| | - Mary L Fischer
- School of Biological Sciences, Illinois State University, Normal, Illinois, United States of America
| | - Joshua Hill
- School of Biological Sciences, Illinois State University, Normal, Illinois, United States of America
| | - Todd A Schlenke
- Department of Entomology, University of Arizona, Tucson, Arizona, United States of America
| | - Nathan T Mortimer
- School of Biological Sciences, Illinois State University, Normal, Illinois, United States of America
- Department of Biochemistry & Biophysics, Oregon State University, Corvallis, Oregon, United States of America
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3
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Makwana P, Hungund SP, Pradeep ANR. Dipteran endoparasitoid Exorista bombycis utilizes antihemocyte components against host defense of silkworm Bombyx mori. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2023; 112:e21976. [PMID: 36205611 DOI: 10.1002/arch.21976] [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: 08/02/2022] [Revised: 09/07/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
Dipteran endoparasitoids avoid host immune response; however, antidefense components from the Dipterans are unknown. Infestation of commercial silkworm Bombyx mori Linnaeus (Lepidoptera: Bombycidae) by endoparasitoid Exorista bombycis Louis (Diptera: Tachinidae) induced immune reactions, cytotoxicity, granulation, degranulation, and augmented release of cytotoxic marker enzyme lactate dehydrogenase (LDH), and degranulation-mediator enzyme β-hexosaminidase in hemocytes. In this study, by reverse phase high-performance liquid chromatography, fractions of E. bombycis larval tissue protein with antihemocytic activity are separated. From the fraction, peptides of hemocyte aggregation inhibitor protein (HAIP) and pyridoxamine phosphate oxidase (PNPO) are identified by mass spectrometry. Interacting partners of HAIP and PNPO are retrieved that further enhance the virulence of the parasitoid. PNPO and HAIP genes showed a four- to seven fold increase in expression in the integument of the parasitoid larva. Together, the dipteran endoparasitoid E. bombycis exploit antihemocyte activity to inhibit host defense reactions in addition to defense evasion contemplated.
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Affiliation(s)
- Pooja Makwana
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Bangalore, Karnataka, India
- Biotechnology Division, Central Sericultural Research & Training Institute, Berhampore, West Bengal, India
| | - Shambhavi P Hungund
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Bangalore, Karnataka, India
| | - Appukuttan Nair R Pradeep
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Bangalore, Karnataka, India
- Biotechnology Division, Central Sericultural Research & Training Institute, Berhampore, West Bengal, India
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4
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Quicray M, Wilhelm L, Enriquez T, He S, Scheifler M, Visser B. The Drosophila-parasitizing wasp Leptopilina heterotoma: A comprehensive model system in ecology and evolution. Ecol Evol 2023; 13:e9625. [PMID: 36703713 PMCID: PMC9871341 DOI: 10.1002/ece3.9625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 01/25/2023] Open
Abstract
The parasitoid Leptopilina heterotoma has been used as a model system for more than 70 years, contributing greatly to diverse research areas in ecology and evolution. Here, we synthesized the large body of work on L. heterotoma with the aim to identify new research avenues that could be of interest also for researchers studying other parasitoids and insects. We start our review with a description of typical L. heterotoma characteristics, as well as that of the higher taxonomic groups to which this species belongs. We then continue discussing host suitability and immunity, foraging behaviors, as well as fat accumulation and life histories. We subsequently shift our focus towards parasitoid-parasitoid interactions, including L. heterotoma coexistence within the larger guild of Drosophila parasitoids, chemical communication, as well as mating and population structuring. We conclude our review by highlighting the assets of L. heterotoma as a model system, including its intermediate life history syndromes, the ease of observing and collecting natural hosts and wasps, as well as recent genomic advances.
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Affiliation(s)
- Maude Quicray
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
| | - Léonore Wilhelm
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
| | - Thomas Enriquez
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
| | - Shulin He
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
| | - Mathilde Scheifler
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
| | - Bertanne Visser
- Evolution and Ecophysiology Group, Department of Functional and Evolutionary EntomologyUniversity of Liège ‐ Gembloux Agro‐Bio TechGemblouxBelgium
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Di Giovanni D, Lepetit D, Guinet B, Bennetot B, Boulesteix M, Couté Y, Bouchez O, Ravallec M, Varaldi J. A Behavior-Manipulating Virus Relative as a Source of Adaptive Genes for Drosophila Parasitoids. Mol Biol Evol 2021; 37:2791-2807. [PMID: 32080746 DOI: 10.1093/molbev/msaa030] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Some species of parasitic wasps have domesticated viral machineries to deliver immunosuppressive factors to their hosts. Up to now, all described cases fall into the Ichneumonoidea superfamily, which only represents around 10% of hymenoptera diversity, raising the question of whether such domestication occurred outside this clade. Furthermore, the biology of the ancestral donor viruses is completely unknown. Since the 1980s, we know that Drosophila parasitoids belonging to the Leptopilina genus, which diverged from the Ichneumonoidea superfamily 225 Ma, do produce immunosuppressive virus-like structure in their reproductive apparatus. However, the viral origin of these structures has been the subject of debate. In this article, we provide genomic and experimental evidence that those structures do derive from an ancestral virus endogenization event. Interestingly, its close relatives induce a behavior manipulation in present-day wasps. Thus, we conclude that virus domestication is more prevalent than previously thought and that behavior manipulation may have been instrumental in the birth of such associations.
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Affiliation(s)
- Deborah Di Giovanni
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
| | - David Lepetit
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
| | - Benjamin Guinet
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
| | - Bastien Bennetot
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France.,Ecologie Systématique & Evolution (UMR 8079), Université Paris Sud, Orsay, France
| | - Matthieu Boulesteix
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
| | - Yohann Couté
- Université de Grenoble Alpes, CEA, Inserm, IRIG-BGE, Grenoble, France
| | - Olivier Bouchez
- Institut National de la Recherche Agronomique (INRA), US 1426, GeT-PlaGe, Genotoul, Castanet-Tolosan, France
| | - Marc Ravallec
- UMR 1333 INRAE - Université Montpellier "Diversité, Génomes et Interactions Microorganismes-Insectes" (DGIMI), Montpellier, France
| | - Julien Varaldi
- Université de Lyon Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
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Kr P, Lee J, Mortimer NT. The S1A protease family members CG10764 and CG4793 regulate cellular immunity in Drosophila. MICROPUBLICATION BIOLOGY 2021; 2021. [PMID: 33644706 PMCID: PMC7900826 DOI: 10.17912/micropub.biology.000370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In nature, Drosophila melanogaster larvae are infected by parasitoid wasps and mount a cellular immune response to this infection. Several conserved signaling pathways have been implicated in coordinating this response, however our understanding of the integration and regulation of these pathways is incomplete. Members of the S1A serine protease family have been previously linked to immune functions, and our findings suggest roles for two S1A family members, CG10764 and CG4793 in the cellular immune response to parasitoid infection.
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Affiliation(s)
- Pooja Kr
- School of Biological Sciences, Illinois State University
| | - Jonathan Lee
- School of Biological Sciences, Illinois State University
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7
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Trainor JE, KR P, Mortimer NT. Immune Cell Production Is Targeted by Parasitoid Wasp Virulence in a Drosophila-Parasitoid Wasp Interaction. Pathogens 2021; 10:49. [PMID: 33429864 PMCID: PMC7826891 DOI: 10.3390/pathogens10010049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 12/29/2020] [Accepted: 01/05/2021] [Indexed: 11/26/2022] Open
Abstract
The interactions between Drosophila melanogaster and the parasitoid wasps that infect Drosophila species provide an important model for understanding host-parasite relationships. Following parasitoid infection, D. melanogaster larvae mount a response in which immune cells (hemocytes) form a capsule around the wasp egg, which then melanizes, leading to death of the parasitoid. Previous studies have found that host hemocyte load; the number of hemocytes available for the encapsulation response; and the production of lamellocytes, an infection induced hemocyte type, are major determinants of host resistance. Parasitoids have evolved various virulence mechanisms to overcome the immune response of the D. melanogaster host, including both active immune suppression by venom proteins and passive immune evasive mechanisms. We identified a previously undescribed parasitoid species, Asobara sp. AsDen, which utilizes an active virulence mechanism to infect D. melanogaster hosts. Asobara sp. AsDen infection inhibits host hemocyte expression of msn, a member of the JNK signaling pathway, which plays a role in lamellocyte production. Asobara sp. AsDen infection restricts the production of lamellocytes as assayed by hemocyte cell morphology and altered msn expression. Our findings suggest that Asobara sp. AsDen infection alters host signaling to suppress immunity.
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Affiliation(s)
| | | | - Nathan T. Mortimer
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA; (J.E.T.); (P.K.)
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8
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Bioinformatic analysis suggests potential mechanisms underlying parasitoid venom evolution and function. Genomics 2019; 112:1096-1104. [PMID: 31247332 DOI: 10.1016/j.ygeno.2019.06.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 06/18/2019] [Accepted: 06/20/2019] [Indexed: 11/21/2022]
Abstract
Hymenopteran parasitoid wasps are a diverse collection of species that infect arthropod hosts and use factors found in their venoms to manipulate host immune responses, physiology, and behaviour. Whole parasitoid venoms have been profiled using proteomic approaches, and here we present a bioinformatic characterization of the venom protein content from Ganaspis sp. 1, a parasitoid that infects flies of the genus Drosophila. We find evidence that diverse evolutionary processes including multifunctionalization, co-option, gene duplication, and horizontal gene transfer may be acting in concert to drive venom gene evolution in Ganaspis sp.1. One major role of parasitoid wasp venom is host immune evasion. We previously demonstrated that Ganaspis sp. 1 venom inhibits immune cell activation in infected Drosophila melanogaster hosts, and our current analysis has uncovered additional predicted virulence functions. Overall, this analysis represents an important step towards understanding the composition and activity of parasitoid wasp venoms.
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9
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Kruitwagen A, Beukeboom LW, Wertheim B. Optimization of native biocontrol agents, with parasitoids of the invasive pest Drosophila suzukii as an example. Evol Appl 2018; 11:1473-1497. [PMID: 30344621 PMCID: PMC6183459 DOI: 10.1111/eva.12648] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 05/03/2018] [Accepted: 05/08/2018] [Indexed: 01/10/2023] Open
Abstract
The development of biological control methods for exotic invasive pest species has become more challenging during the last decade. Compared to indigenous natural enemies, species from the pest area of origin are often more efficient due to their long coevolutionary history with the pest. The import of these well-adapted exotic species, however, has become restricted under the Nagoya Protocol on Access and Benefit Sharing, reducing the number of available biocontrol candidates. Finding new agents and ways to improve important traits for control agents ("biocontrol traits") is therefore of crucial importance. Here, we demonstrate the potential of a surprisingly under-rated method for improvement of biocontrol: the exploitation of intraspecific variation in biocontrol traits, for example, by selective breeding. We propose a four-step approach to investigate the potential of this method: investigation of the amount of (a) inter- and (b) intraspecific variation for biocontrol traits, (c) determination of the environmental and genetic factors shaping this variation, and (d) exploitation of this variation in breeding programs. We illustrate this approach with a case study on parasitoids of Drosophila suzukii, a highly invasive pest species in Europe and North America. We review all known parasitoids of D. suzukii and find large variation among and within species in their ability to kill this fly. We then consider which genetic and environmental factors shape the interaction between D. suzukii and its parasitoids to explain this variation. Insight into the causes of variation informs us on how and to what extent candidate agents can be improved. Moreover, it aids in predicting the effectiveness of the agent upon release and provides insight into the selective forces that are limiting the adaptation of indigenous species to the new pest. We use this knowledge to give future research directions for the development of selective breeding methods for biocontrol agents.
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Affiliation(s)
- Astrid Kruitwagen
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Leo W. Beukeboom
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Bregje Wertheim
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
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10
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Letourneau M, Lapraz F, Sharma A, Vanzo N, Waltzer L, Crozatier M. Drosophila hematopoiesis under normal conditions and in response to immune stress. FEBS Lett 2016; 590:4034-4051. [PMID: 27455465 DOI: 10.1002/1873-3468.12327] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/07/2016] [Accepted: 07/21/2016] [Indexed: 12/12/2022]
Abstract
The emergence of hematopoietic progenitors and their differentiation into various highly specialized blood cell types constitute a finely tuned process. Unveiling the genetic cascades that control blood cell progenitor fate and understanding how they are modulated in response to environmental changes are two major challenges in the field of hematopoiesis. In the last 20 years, many studies have established important functional analogies between blood cell development in vertebrates and in the fruit fly, Drosophila melanogaster. Thereby, Drosophila has emerged as a powerful genetic model for studying mechanisms that control hematopoiesis during normal development or in pathological situations. Moreover, recent advances in Drosophila have highlighted how intricate cell communication networks and microenvironmental cues regulate blood cell homeostasis. They have also revealed the striking plasticity of Drosophila mature blood cells and the presence of different sites of hematopoiesis in the larva. This review provides an overview of Drosophila hematopoiesis during development and summarizes our current knowledge on the molecular processes controlling larval hematopoiesis, both under normal conditions and in response to an immune challenge, such as wasp parasitism.
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Affiliation(s)
- Manon Letourneau
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France
| | - Francois Lapraz
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France
| | - Anurag Sharma
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France.,Department of Biomedical Sciences, NU Centre for Science Education & Research, Nitte University, Mangalore-18, India
| | - Nathalie Vanzo
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France
| | - Lucas Waltzer
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France
| | - Michèle Crozatier
- Centre de Biologie du Développement, UMR 5547 CNRS/Université Toulouse III and Centre de Biologie Intégrative, Toulouse Cedex 9, France
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11
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The Role of Lipid Competition for Endosymbiont-Mediated Protection against Parasitoid Wasps in Drosophila. mBio 2016; 7:mBio.01006-16. [PMID: 27406568 PMCID: PMC4958261 DOI: 10.1128/mbio.01006-16] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Insects commonly harbor facultative bacterial endosymbionts, such as Wolbachia and Spiroplasma species, that are vertically transmitted from mothers to their offspring. These endosymbiontic bacteria increase their propagation by manipulating host reproduction or by protecting their hosts against natural enemies. While an increasing number of studies have reported endosymbiont-mediated protection, little is known about the mechanisms underlying this protection. Here, we analyze the mechanisms underlying protection from parasitoid wasps in Drosophila melanogaster mediated by its facultative endosymbiont Spiroplasma poulsonii. Our results indicate that S. poulsonii exerts protection against two distantly related wasp species, Leptopilina boulardi and Asobara tabida. S. poulsonii-mediated protection against parasitoid wasps takes place at the pupal stage and is not associated with an increased cellular immune response. In this work, we provide three important observations that support the notion that S. poulsonii bacteria and wasp larvae compete for host lipids and that this competition underlies symbiont-mediated protection. First, lipid quantification shows that both S. poulsonii and parasitoid wasps deplete D. melanogaster hemolymph lipids. Second, the depletion of hemolymphatic lipids using the Lpp RNA interference (Lpp RNAi) construct reduces wasp success in larvae that are not infected with S. poulsonii and blocks S. poulsonii growth. Third, we show that the growth of S. poulsonii bacteria is not affected by the presence of the wasps, indicating that when S. poulsonii is present, larval wasps will develop in a lipid-depleted environment. We propose that competition for host lipids may be relevant to endosymbiont-mediated protection in other systems and could explain the broad spectrum of protection provided. Virtually all insects, including crop pests and disease vectors, harbor facultative bacterial endosymbionts. They are vertically transmitted from mothers to their offspring, and some protect their host against pathogens. Here, we studied the mechanism of protection against parasitoid wasps mediated by the Drosophila melanogaster endosymbiont Spiroplasma poulsonii. Using genetic manipulation of the host, we provide strong evidence supporting the hypothesis that competition for host lipids underlies S. poulsonii-mediated protection against parasitoid wasps. We propose that lipid competition-based protection may not be restricted to Spiroplasma bacteria but could also apply other endosymbionts, notably Wolbachia bacteria, which can suppress human disease-causing viruses in insect hosts.
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12
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Mateos M, Winter L, Winter C, Higareda-Alvear VM, Martinez-Romero E, Xie J. Independent origins of resistance or susceptibility of parasitic wasps to a defensive symbiont. Ecol Evol 2016; 6:2679-87. [PMID: 27066241 PMCID: PMC4798148 DOI: 10.1002/ece3.2085] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/10/2016] [Accepted: 02/22/2016] [Indexed: 01/06/2023] Open
Abstract
Insect microbe associations are diverse, widespread, and influential. Among the fitness effects of microbes on their hosts, defense against natural enemies is increasingly recognized as ubiquitous, particularly among those associations involving heritable, yet facultative, bacteria. Protective mutualisms generate complex ecological and coevolutionary dynamics that are only beginning to be elucidated. These depend in part on the degree to which symbiont‐mediated protection exhibits specificity to one or more members of the natural enemy community. Recent findings in a well‐studied defensive mutualism system (i.e., aphids, bacteria, parasitoid wasps) reveal repeated instances of evolution of susceptibility or resistance to defensive bacteria by parasitoids. This study searched for similar patterns in an emerging model system for defensive mutualisms: the interaction of Drosophila, bacteria in the genus Spiroplasma, and wasps that parasitize larval stages of Drosophila. Previous work indicated that three divergent species of parasitic wasps are strongly inhibited by the presence of Spiroplasma in three divergent species of Drosophila, including D. melanogaster. The results of this study uncovered two additional wasp species that are susceptible to Spiroplasma and two that are unaffected by Spiroplasma, implying at least two instances of loss or gain of susceptibility to Spiroplasma among larval parasitoids of Drosophila.
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Affiliation(s)
- Mariana Mateos
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | - Lauryn Winter
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | - Caitlyn Winter
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | | | | | - Jialei Xie
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
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