1
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Krueger SK, Williams SC, O’Keefe JM, Zirkle GA, Haase CG. White-nose syndrome, winter duration, and pre-hibernation climate impact abundance of reproductive female bats. PLoS One 2024; 19:e0298515. [PMID: 38669238 PMCID: PMC11051637 DOI: 10.1371/journal.pone.0298515] [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: 08/22/2023] [Accepted: 01/26/2024] [Indexed: 04/28/2024] Open
Abstract
White-nose syndrome (WNS) is an infectious disease that disrupts hibernation in bats, leading to premature exhaustion of fat stores. Though we know WNS does impact reproduction in hibernating female bats, we are unsure how these impacts are exacerbated by local climate factors. We compiled data from four southeastern U.S. states and used generalized linear mixed effects models to compare effects of WNS, pre-hibernation climate variables, and winter duration on the number of reproductive females in species across the range of WNS susceptibility. We predicted we would see a decline in the number of reproductive females in WNS-susceptible species, with the effect exaggerated by longer winter durations and pre-hibernation climate variables that lead to reductions in foraging. We found that the number of reproductive females in WNS-susceptible species was positively correlated with pre-hibernation local climate conditions conducive to foraging; however, WNS-susceptible species experienced an overall decline with the presence of WNS and as winter duration increased. Our long-term dataset provides evidence that pre-hibernation climate, specifically favorable summer weather conditions for foraging, greatly influences the reproduction, regardless of WNS status.
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Affiliation(s)
- Sarah K. Krueger
- Department of Biology, Austin Peay State University, Clarksville, Tennessee, United States of America
| | - Sarah C. Williams
- Environmental Division, US Army Fort Campbell, Fort Campbell, Kentucky, United States of America
| | - Joy M. O’Keefe
- Department of Natural Resources and Environmental Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Gene A. Zirkle
- Environmental Division, US Army Fort Campbell, Fort Campbell, Kentucky, United States of America
| | - Catherine G. Haase
- Department of Biology, Austin Peay State University, Clarksville, Tennessee, United States of America
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2
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Whiting-Fawcett F, Blomberg AS, Troitsky T, Meierhofer MB, Field KA, Puechmaille SJ, Lilley TM. A Palearctic view of a bat fungal disease. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024:e14265. [PMID: 38616727 DOI: 10.1111/cobi.14265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/02/2024] [Accepted: 01/20/2024] [Indexed: 04/16/2024]
Abstract
The fungal infection causing white-nose disease in hibernating bats in North America has resulted in dramatic population declines of affected species, since the introduction of the causative agent Pseudogymnoascus destructans. The fungus is native to the Palearctic, where it also infects several bat species, yet rarely causes severe pathology or the death of the host. Pseudogymnoascus destructans infects bats during hibernation by invading and digesting the skin tissue, resulting in the disruption of torpor patterns and consequent emaciation. Relations among pathogen, host, and environment are complex, and individuals, populations, and species respond to the fungal pathogen in different ways. For example, the Nearctic Myotis lucifugus responds to infection by mounting a robust immune response, leading to immunopathology often contributing to mortality. In contrast, the Palearctic M. myotis shows no significant immunological response to infection. This lack of a strong response, resulting from the long coevolution between the hosts and the pathogen in the pathogen's native range, likely contributes to survival in tolerant species. After more than 15 years since the initial introduction of the fungus to North America, some of the affected populations are showing signs of recovery, suggesting that the fungus, hosts, or both are undergoing processes that may eventually lead to coexistence. The suggested or implemented management methods of the disease in North America have encompassed, for example, the use of probiotics and fungicides, vaccinations, and modifying the environmental conditions of the hibernation sites to limit the growth of the pathogen, intensity of infection, or the hosts' responses to it. Based on current knowledge from Eurasia, policy makers and conservation managers should refrain from disrupting the ongoing evolutionary processes and adopt a holistic approach to managing the epizootic.
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Affiliation(s)
- F Whiting-Fawcett
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool, UK
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - A S Blomberg
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - T Troitsky
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - M B Meierhofer
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - K A Field
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, USA
| | - S J Puechmaille
- Institut des Sciences de l'Évolution Montpellier (ISEM), University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
| | - T M Lilley
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
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3
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Li A, Leng H, Li Z, Jin L, Sun K, Feng J. Temporal dynamics of the bat wing transcriptome: Insight into gene-expression changes that enable protection against pathogen. Virulence 2023; 14:2156185. [PMID: 36599840 PMCID: PMC9815227 DOI: 10.1080/21505594.2022.2156185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Skin acts as a mechanical barrier between the body and its surrounding environment and plays an important role in resistance to pathogens. However, we still know little regarding skin responses to physiological changes, particularly with regard to responses against potential pathogens. We herein executed RNA-seq on the wing of the Rhinolophus ferrumequinum to assess gene-expression variations at four physiological stages: pre-hibernation, hibernation (early-hibernation and late-hibernation), and post-hibernation, as well as the gene-expression patterns of infected and uninfected bats with the Pseudogymnoascus destructans (Pd). Our results showed that a greater number of differentially expressed genes between the more disparate physiological stages. Functional enrichment analysis showed that the down-regulated response pathways in hibernating bats included phosphorus metabolism and immune response, indicating metabolic suppression and decreased whole immune function. We also found up-regulated genes in post-hibernating bats that included C-type lectin receptor signalling, Toll-like receptor signalling pathway, and cell adhesion, suggesting that the immune response and skin integrity of the wing were improved after bats emerged from their hibernation and that this facilitated clearing Pd from the integument. Additionally, we found that the genes involved in cytokine or chemokine activity were up-regulated in late-hibernation compared to early-hibernation and that FOSB regulation of immune cell activation was differentially expressed in bats infected with Pd during late-hibernation, implying that the host's innate immune function was enhanced during late-hibernation so as to resist pathogenic infection. Our findings highlight the concept that maintenance of intrinsic immunity provides protection against pathogenic infections in highly resistant bats.
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Affiliation(s)
- Aoqiang Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China,School of Life Sciences, Central China Normal University, Wuhan, China
| | - Haixia Leng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
| | - Zhongle Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China,College of Life Science, Jilin Agricultural University, Changchun, China
| | - Longru Jin
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
| | - Keping Sun
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China,CONTACT Keping Sun
| | - Jiang Feng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China,College of Life Science, Jilin Agricultural University, Changchun, China,Jiang Feng
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4
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Winter torpor expression varies in four bat species with differential susceptibility to white-nose syndrome. Sci Rep 2022; 12:5688. [PMID: 35383238 PMCID: PMC8983705 DOI: 10.1038/s41598-022-09692-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/28/2022] [Indexed: 01/11/2023] Open
Abstract
Studies examining the overwintering behaviors of North American hibernating bats are limited to a handful of species. We deployed temperature-sensitive transmitters on four species of bat that exhibit differences in their susceptibility to white nose syndrome (WNS; Myotis grisescens, M. leibii, M. sodalis, and Perimyotis subflavus) to determine if these differences are correlated with behavior exhibited during hibernation (i.e., torpor expression and arousal frequency). Mean torpor skin temperature (Tsk) and torpor bout duration varied significantly among species (P ≤ 0.024), but arousal Tsk and duration did not (P ≥ 0.057). One of the species with low susceptibility to WNS, M. leibii, had significantly shorter torpor bout durations (37.67 ± 26.89 h) than M. sodalis (260.67 ± 41.33 h), the species with medium susceptibility to WNS. Myotis leibii also had significantly higher torpor Tsk (18.57 °C ± 0.20) than M. grisescens (13.33 °C ± 0.60), a second species with low WNS susceptibility. The high susceptibility species, Perimyotis subflavus, exhibited low torpor Tsk (14.42 °C ± 0.36) but short torpor bouts (72.36 ± 32.16 h). We demonstrate that the four cavernicolous species examined exhibit a wide range in torpid skin temperature and torpor bout duration. Information from this study may improve WNS management in multispecies hibernacula or individual species management by providing insight into how some species may differ in their techniques for overwinter survival.
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5
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Eskew EA, Fraser D, Vonhof MJ, Pinsky ML, Maslo B. Host gene expression in wildlife disease: making sense of species-level responses. Mol Ecol 2021; 30:6517-6530. [PMID: 34516689 DOI: 10.1111/mec.16172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 08/16/2021] [Accepted: 08/31/2021] [Indexed: 12/11/2022]
Abstract
Emerging infectious diseases are significant threats to wildlife conservation, yet the impacts of pathogen exposure and infection can vary widely among host species. As such, conservation biologists and disease ecologists have increasingly aimed to understand species-specific host susceptibility using molecular methods. In particular, comparative gene expression assays have been used to contrast the transcriptomic responses of disease-resistant and disease-susceptible hosts to pathogen exposure. This work usually assumes that the gene expression responses of disease-resistant species will reveal the activation of molecular pathways contributing to host defence. However, results often show that disease-resistant hosts undergo little gene expression change following pathogen challenge. Here, we discuss the mechanistic implications of these "null" findings and offer methodological suggestions for future molecular studies of wildlife disease. First, we highlight that muted transcriptomic responses with minimal immune system recruitment may indeed be protective for nonsusceptible hosts if they limit immunopathology and promote pathogen tolerance in systems where susceptible hosts suffer from genetic dysregulation. Second, we argue that overly narrow investigation of responses to pathogen exposure may overlook important, constitutively active molecular pathways that underlie species-specific defences. Finally, we outline alternative study designs and approaches that complement interspecific transcriptomic comparisons, including intraspecific gene expression studies and genomic methods to detect signatures of selection. Collectively, these insights will help ecologists extract maximal information from conservation-relevant transcriptomic data sets, leading to a deeper understanding of host defences and, ultimately, the implementation of successful conservation interventions.
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Affiliation(s)
- Evan A Eskew
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA.,Department of Biology, Pacific Lutheran University, Tacoma, Washington, USA
| | - Devaughn Fraser
- Wildlife Genetics Research Laboratory, California Department of Fish and Wildlife, Sacramento, California, USA
| | - Maarten J Vonhof
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan, USA
| | - Malin L Pinsky
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Brooke Maslo
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
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6
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Robinson CV, Robinson JM. Listen But Do Not Touch: Using a Smartphone Acoustic Device to Investigate Bat Activity, with Implications for Community-Based Monitoring. ACTA CHIROPTEROLOGICA 2021. [DOI: 10.3161/15081109acc2021.23.1.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Chloe V. Robinson
- Integrative Biology, Centre for Biodiversity Genomics, University of Guelph, 50 Stone Road E, Guelph, ON, N1G 2W1, Canada
| | - Jessica M. Robinson
- Integrative Biology, Centre for Biodiversity Genomics, University of Guelph, 50 Stone Road E, Guelph, ON, N1G 2W1, Canada
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7
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Tobias ZJC, Fowler AE, Blakeslee AMH, Darling JA, Torchin ME, Miller AW, Ruiz GM, Tepolt CK. Invasion history shapes host transcriptomic response to a body-snatching parasite. Mol Ecol 2021; 30:4321-4337. [PMID: 34162013 PMCID: PMC10128110 DOI: 10.1111/mec.16038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 05/27/2021] [Accepted: 06/11/2021] [Indexed: 01/04/2023]
Abstract
By shuffling biogeographical distributions, biological invasions can both disrupt long-standing associations between hosts and parasites and establish new ones. This creates natural experiments with which to study the ecology and evolution of host-parasite interactions. In estuaries of the Gulf of Mexico, the white-fingered mud crab (Rhithropanopeus harrisii) is infected by a native parasitic barnacle, Loxothylacus panopaei (Rhizocephala), which manipulates host physiology and behaviour. In the 1960s, L. panopaei was introduced to the Chesapeake Bay and has since expanded along the southeastern Atlantic coast, while host populations in the northeast have so far been spared. We use this system to test the host's transcriptomic response to parasitic infection and investigate how this response varies with the parasite's invasion history, comparing populations representing (i) long-term sympatry between host and parasite, (ii) new associations where the parasite has invaded during the last 60 years and (iii) naïve hosts without prior exposure. A comparison of parasitized and control crabs revealed a core response, with widespread downregulation of transcripts involved in immunity and moulting. The transcriptional response differed between hosts from the parasite's native range and where it is absent, consistent with previous observations of increased susceptibility in populations lacking exposure to the parasite. Crabs from the parasite's introduced range, where prevalence is highest, displayed the most dissimilar response, possibly reflecting immune priming. These results provide molecular evidence for parasitic manipulation of host phenotype and the role of gene regulation in mediating host-parasite interactions.
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Affiliation(s)
- Zachary J C Tobias
- MIT-WHOI Joint Program in Oceanography/Applied Ocean Science and Engineering, Cambridge and Woods Hole, MA, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.,Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Amy E Fowler
- Department of Environmental Science and Policy, George Mason University, Fairfax, VA, USA
| | | | - John A Darling
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Mark E Torchin
- Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama
| | | | - Gregory M Ruiz
- Smithsonian Environmental Research Center, Edgewater, MD, USA
| | - Carolyn K Tepolt
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.,Smithsonian Environmental Research Center, Edgewater, MD, USA
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8
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Abstract
The recent introduction of Pseudogymnoascus destructans (the fungal pathogen that causes white-nose syndrome in bats) from Eurasia to North America has resulted in the collapse of North American bat populations and restructured species communities. The long evolutionary history between P. destructans and bats in Eurasia makes understanding host life history essential to uncovering the ecology of P. destructans. In this Review, we combine information on pathogen and host biology to understand the patterns of P. destructans spread, seasonal transmission ecology, the pathogenesis of white-nose syndrome and the cross-scale impact from individual hosts to ecosystems. Collectively, this research highlights how early pathogen detection and quantification of host impacts has accelerated the understanding of this newly emerging infectious disease.
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9
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Simonis MC, Brown BKG, Bahn V. Mobile Bat Acoustic Routes Indicate Cavity-Roosting Species Undergo Compensatory Changes in Community Composition Following White-Nose Syndrome. ACTA CHIROPTEROLOGICA 2020. [DOI: 10.3161/15081109acc2020.22.2.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Molly C. Simonis
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, USA
| | - Bridget K. G. Brown
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 318W 12th Avenue, Columbus, OH 43210, USA
| | - Volker Bahn
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, USA
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10
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Davy CM, Donaldson ME, Bandouchova H, Breit AM, Dorville NA, Dzal YA, Kovacova V, Kunkel EL, Martínková N, Norquay KJ, Paterson JE, Zukal J, Pikula J, Willis CK, Kyle CJ. Transcriptional host-pathogen responses of Pseudogymnoascus destructans and three species of bats with white-nose syndrome. Virulence 2020; 11:781-794. [PMID: 32552222 PMCID: PMC7549942 DOI: 10.1080/21505594.2020.1768018] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 03/07/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Understanding how context (e.g., host species, environmental conditions) drives disease susceptibility is an essential goal of disease ecology. We hypothesized that in bat white-nose syndrome (WNS), species-specific host-pathogen interactions may partly explain varying disease outcomes among host species. We characterized bat and pathogen transcriptomes in paired samples of lesion-positive and lesion-negative wing tissue from bats infected with Pseudogymnoascus destructans in three parallel experiments. The first two experiments analyzed samples collected from the susceptible Nearctic Myotis lucifugus and the less-susceptible Nearctic Eptesicus fuscus, following experimental infection and hibernation in captivity under controlled conditions. The third experiment applied the same analyses to paired samples from infected, free-ranging Myotis myotis, a less susceptible, Palearctic species, following natural infection and hibernation (n = 8 sample pairs/species). Gene expression by P. destructans was similar among the three host species despite varying environmental conditions among the three experiments and was similar within each host species between saprophytic contexts (superficial growth on wings) and pathogenic contexts (growth in lesions on the same wings). In contrast, we observed qualitative variation in host response: M. lucifugus and M. myotis exhibited systemic responses to infection, while E. fuscus up-regulated a remarkably localized response. Our results suggest potential phylogenetic determinants of response to WNS and can inform further studies of context-dependent host-pathogen interactions.
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Affiliation(s)
- Christina M. Davy
- Environmental and Life Sciences Program, Trent University, Peterborough, Canada
- Wildlife Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry, Peterborough, Canada
| | | | - Hana Bandouchova
- Department of Ecology and Diseases of Game, Fish and Bees, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic
| | - Ana M. Breit
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Nicole A.S. Dorville
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Yvonne A. Dzal
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Veronika Kovacova
- Department of Ecology and Diseases of Game, Fish and Bees, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic
| | - Emma L. Kunkel
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Natália Martínková
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
| | - Kaleigh J.O. Norquay
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - James E. Paterson
- Environmental and Life Sciences Program, Trent University, Peterborough, Canada
| | - Jan Zukal
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
| | - Jiri Pikula
- Department of Ecology and Diseases of Game, Fish and Bees, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic
| | - Craig K.R. Willis
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Christopher J. Kyle
- Environmental and Life Sciences Program, Trent University, Peterborough, Canada
- Natural Resources DNA Profiling and Forensics Centre, Trent University, Peterborough, Canada
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11
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Bernard RF, Reichard JD, Coleman JTH, Blackwood JC, Verant ML, Segers JL, Lorch JM, White J, Moore MS, Russell AL, Katz RA, Lindner DL, Toomey RS, Turner GG, Frick WF, Vonhof MJ, Willis CKR, Grant EHC. Identifying research needs to inform white‐nose syndrome management decisions. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.220] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Riley F. Bernard
- Department of Ecosystem Science and ManagementPennsylvania State University University Park Pennsylvania USA
- United States Geological Survey Patuxent Wildlife Research CenterSO Conte Anadromous Fish Research Laboratory Turners Falls Massachusetts USA
| | | | | | - Julie C. Blackwood
- Department of Mathematics and StatisticsWilliams College Williamstown Massachusetts USA
| | - Michelle L. Verant
- Biological Resource DivisionWildlife Health Branch Fort Collins Colorado USA
| | - Jordi L. Segers
- Canadian Wildlife Health Cooperative Charlottetown Prince Edward Island Canada
| | - Jeffery M. Lorch
- United States Geological Survey National Wildlife Health Center Madison Wisconsin USA
| | - John White
- Bureau of Natural Heritage ConservationWisconsin Department of Natural Resources Madison Wisconsin USA
| | - Marianne S. Moore
- College of Integrative Science and ArtsArizona State University Mesa Arizona USA
| | - Amy L. Russell
- Department of BiologyGrand Valley State University Allendale Michigan USA
| | - Rachel A. Katz
- United States Fish and Wildlife Service Hadley Massachusetts USA
| | - Daniel L. Lindner
- United States Forest ServiceNorthern Research Station Madison Wisconsin USA
| | | | | | - Winifred F. Frick
- Department of Ecology and Evolutionary BiologyUniversity of California Santa Cruz California USA
- Bat Conservation International Austin Texas USA
| | - Maarten J. Vonhof
- Department of Biological SciencesWestern Michigan University Kalamazoo Michigan USA
- Institute of the Environment and SustainabilityWestern Michigan University Kalamazoo Michigan USA
| | | | - Evan H. C. Grant
- United States Geological Survey Patuxent Wildlife Research CenterSO Conte Anadromous Fish Research Laboratory Turners Falls Massachusetts USA
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12
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Hecht-Höger AM, Braun BC, Krause E, Meschede A, Krahe R, Voigt CC, Greenwood AD, Czirják GÁ. Plasma proteomic profiles differ between European and North American myotid bats colonized by Pseudogymnoascus destructans. Mol Ecol 2020; 29:1745-1755. [PMID: 32279365 DOI: 10.1111/mec.15437] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 03/27/2020] [Accepted: 04/01/2020] [Indexed: 12/18/2022]
Abstract
Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white-nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats. Differences in epidemiology and pathology indicate an evolution of resistance or tolerance mechanisms towards Pd in European bats. We compared the proteomic profile of blood plasma in healthy and Pd-colonized European Myotis myotis and North American Myotis lucifugus in order to identify pathophysiological changes associated with Pd colonization, which might also explain the differences in bat survival. Expression analyses of plasma proteins revealed differences in healthy and Pd-colonized M. lucifugus, but not in M. myotis. We identified differentially expressed proteins for acute phase response, constitutive and adaptive immunity, oxidative stress defence, metabolism and structural proteins of exosomes and desmosomes, suggesting a systemic response against Pd in North American M. lucifugus but not European M. myotis. The differences in plasma proteomic profiles between European and North American bat species colonized by Pd suggest European bats have evolved tolerance mechanisms towards Pd infection.
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Affiliation(s)
| | - Beate C Braun
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Eberhard Krause
- Leibniz Institute for Molecular Pharmacology, Berlin, Germany
| | - Angelika Meschede
- Institute of Zoology II, University of Erlangen-Nuremberg, Erlangen, Germany
| | | | - Christian C Voigt
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.,Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Alex D Greenwood
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.,Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Gábor Á Czirják
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
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13
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Auteri GG, Knowles LL. Decimated little brown bats show potential for adaptive change. Sci Rep 2020; 10:3023. [PMID: 32080246 PMCID: PMC7033193 DOI: 10.1038/s41598-020-59797-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/04/2020] [Indexed: 11/25/2022] Open
Abstract
The degree to which species can rapidly adapt is key to survival in the face of climatic and other anthropogenic changes. For little brown bats (Myotis lucifugus), whose populations have experienced declines of over 90% because of the introduced fungal pathogen that causes white-nose syndrome (WNS), survival of the species may ultimately depend upon its capacity for adaptive change. Here, we present evidence of selectively driven change (adaptation), despite dramatic nonadaptive genomic shifts (genetic drift) associated with population declines. We compared the genetic makeups of wild survivors versus non-survivors of WNS, and found significant shifts in allele frequencies of genes associated with regulating arousal from hibernation (GABARB1), breakdown of fats (cGMP-PK1), and vocalizations (FOXP2). Changes at these genes are suggestive of evolutionary adaptation, given that WNS causes bats to arouse with unusual frequency from hibernation, contributing to premature depletion of fat reserves. However, whether these putatively adaptive shifts in allele frequencies translate into sufficient increases in survival for the species to rebound in the face of WNS is unknown.
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Affiliation(s)
- Giorgia G Auteri
- Department of Ecology and Evolutionary Biology and Museum of Zoology, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - L Lacey Knowles
- Department of Ecology and Evolutionary Biology and Museum of Zoology, University of Michigan, Ann Arbor, MI, 48109, USA
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14
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Bracamonte SE, Johnston PR, Monaghan MT, Knopf K. Gene expression response to a nematode parasite in novel and native eel hosts. Ecol Evol 2019; 9:13069-13084. [PMID: 31871630 PMCID: PMC6912882 DOI: 10.1002/ece3.5728] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/19/2019] [Accepted: 09/19/2019] [Indexed: 01/19/2023] Open
Abstract
Invasive parasites are involved in population declines of new host species worldwide. The high susceptibilities observed in many novel hosts have been attributed to the lack of protective immunity to the parasites which native hosts acquired during their shared evolution. We experimentally infected Japanese eels (Anguilla japonica) and European eels (Anguilla anguilla) with Anguillicola crassus, a nematode parasite that is native to the Japanese eel and invasive in the European eel. We inferred gene expression changes in head kidney tissue from both species, using RNA-seq data to determine the responses at two time points during the early stages of infection (3 and 23 days postinfection). At both time points, the novel host modified the expression of a larger and functionally more diverse set of genes than the native host. Strikingly, the native host regulated immune gene expression only at the earlier time point and to a small extent while the novel host regulated these genes at both time points. A low number of differentially expressed immune genes, especially in the native host, suggest that a systemic immune response was of minor importance during the early stages of infection. Transcript abundance of genes involved in cell respiration was reduced in the novel host which may affect its ability to cope with harsh conditions and energetically demanding activities. The observed gene expression changes in response to a novel parasite that we observed in a fish follow a general pattern observed in amphibians and mammals, and suggest that the disruption of physiological processes, rather than the absence of an immediate immune response, is responsible for the higher susceptibility of the novel host.
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Affiliation(s)
- Seraina E. Bracamonte
- Leibniz‐Institute of Freshwater Ecology and Inland FisheriesBerlinGermany
- Berlin Center for Genomics in Biodiversity ResearchBerlinGermany
- Faculty of Life SciencesHumboldt‐Universität zu BerlinBerlinGermany
| | - Paul R. Johnston
- Leibniz‐Institute of Freshwater Ecology and Inland FisheriesBerlinGermany
- Berlin Center for Genomics in Biodiversity ResearchBerlinGermany
- Institut für BiologieFreie Universität BerlinBerlinGermany
| | - Michael T. Monaghan
- Leibniz‐Institute of Freshwater Ecology and Inland FisheriesBerlinGermany
- Berlin Center for Genomics in Biodiversity ResearchBerlinGermany
- Institut für BiologieFreie Universität BerlinBerlinGermany
| | - Klaus Knopf
- Leibniz‐Institute of Freshwater Ecology and Inland FisheriesBerlinGermany
- Faculty of Life SciencesHumboldt‐Universität zu BerlinBerlinGermany
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15
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Lilley TM, Prokkola JM, Blomberg AS, Paterson S, Johnson JS, Turner GG, Bartonička T, Bachorec E, Reeder DM, Field KA. Resistance is futile: RNA-sequencing reveals differing responses to bat fungal pathogen in Nearctic Myotis lucifugus and Palearctic Myotis myotis. Oecologia 2019; 191:295-309. [PMID: 31506746 PMCID: PMC6763535 DOI: 10.1007/s00442-019-04499-6] [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: 08/07/2019] [Accepted: 08/30/2019] [Indexed: 12/18/2022]
Abstract
Abstract Resistance and tolerance allow organisms to cope with potentially life-threatening pathogens. Recently introduced pathogens initially induce resistance responses, but natural selection favors the development of tolerance, allowing for a commensal relationship to evolve. Mycosis by Pseudogymnoascus destructans, causing white-nose syndrome (WNS) in Nearctic hibernating bats, has resulted in population declines since 2006. The pathogen, which spread from Europe, has infected species of Palearctic Myotis for a longer period. We compared ecologically relevant responses to the fungal infection in the susceptible Nearctic M. lucifugus and less susceptible Palearctic M. myotis, to uncover factors contributing to survival differences in the two species. Samples were collected from euthermic bats during arousal from hibernation, a naturally occurring phenomenon, during which transcriptional responses are activated. We compared the whole-transcriptome responses in wild bats infected with P. destructans hibernating in their natural habitat. Our results show dramatically different local transcriptional responses to the pathogen between uninfected and infected samples from the two species. Whereas we found 1526 significantly upregulated or downregulated transcripts in infected M. lucifugus, only one transcript was downregulated in M. myotis. The upregulated response pathways in M. lucifugus include immune cell activation and migration, and inflammatory pathways, indicative of an unsuccessful attempt to resist the infection. In contrast, M. myotis appears to tolerate P. destructans infection by not activating a transcriptional response. These host-microbe interactions determine pathology, contributing to WNS susceptibility, or commensalism, promoting tolerance to fungal colonization during hibernation that favors survival. Graphic abstract ![]()
Electronic supplementary material The online version of this article (10.1007/s00442-019-04499-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Thomas M Lilley
- Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland.
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK.
| | - Jenni M Prokkola
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | - Steve Paterson
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Joseph S Johnson
- Department of Biological Sciences, Ohio University, Athens, OH, USA
| | | | - Tomáš Bartonička
- Department of Botany and Zoology, Masaryk University, Brno, Czech Republic
| | - Erik Bachorec
- Department of Botany and Zoology, Masaryk University, Brno, Czech Republic
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16
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White-nose syndrome is associated with increased replication of a naturally persisting coronaviruses in bats. Sci Rep 2018; 8:15508. [PMID: 30341341 PMCID: PMC6195612 DOI: 10.1038/s41598-018-33975-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 10/09/2018] [Indexed: 01/08/2023] Open
Abstract
Spillover of viruses from bats to other animals may be associated with increased contact between them, as well as increased shedding of viruses by bats. Here, we tested the prediction that little brown bats (Myotis lucifugus) co-infected with the M. lucifugus coronavirus (Myl-CoV) and with Pseudogymnoascus destructans (Pd), the fungus that causes bat white-nose syndrome (WNS), exhibit different disease severity, viral shedding and molecular responses than bats infected with only Myl-CoV or only P. destructans. We took advantage of the natural persistence of Myl-CoV in bats that were experimentally inoculated with P. destructans in a previous study. Here, we show that the intestines of virus-infected bats that were also infected with fungus contained on average 60-fold more viral RNA than bats with virus alone. Increased viral RNA in the intestines correlated with the severity of fungus-related pathology. Additionally, the intestines of bats infected with fungus exhibited different expression of mitogen-activated protein kinase pathway and cytokine related transcripts, irrespective of viral presence. Levels of coronavirus antibodies were also higher in fungal-infected bats. Our results suggest that the systemic effects of WNS may down-regulate anti-viral responses in bats persistently infected with M. lucifugus coronavirus and increase the potential of virus shedding.
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17
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Davy CM, Donaldson ME, Willis CKR, Saville BJ, McGuire LP, Mayberry H, Wilcox A, Wibbelt G, Misra V, Kyle CJ. Environmentally persistent pathogens present unique challenges for studies of host-pathogen interactions: Reply to Field (2018). Ecol Evol 2018; 8:5238-5241. [PMID: 29938048 PMCID: PMC6010918 DOI: 10.1002/ece3.4035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Linked article: https://doi.org/10.1002/ece3.4034.
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Affiliation(s)
- Christina M. Davy
- Environmental and Life Sciences Graduate ProgramTrent UniversityPeterboroughONCanada
- Wildlife Research and Monitoring SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
| | - Michael E. Donaldson
- Environmental and Life Sciences Graduate ProgramTrent UniversityPeterboroughONCanada
| | - Craig K. R. Willis
- Wildlife Research and Monitoring SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
| | | | - Liam P. McGuire
- Wildlife Research and Monitoring SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
- Department of Biological SciencesTexas Tech UniversityLubbockTXUSA
| | - Heather Mayberry
- Wildlife Research and Monitoring SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
| | - Alana Wilcox
- Wildlife Research and Monitoring SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
| | - Gudrun Wibbelt
- Leibniz Institute of Zoo and Wildlife ResearchBerlinGermany
| | - Vikram Misra
- Department of MicrobiologyWestern College of Vet. MedicineUniversity of SaskatchewanSaskatoonSKCanada
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18
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Donaldson ME, Davy CM, Vanderwolf KJ, Willis CKR, Saville BJ, Kyle CJ. Growth medium and incubation temperature alter the Pseudogymnoascus destructans transcriptome: implications in identifying virulence factors. Mycologia 2018; 110:300-315. [PMID: 29737946 DOI: 10.1080/00275514.2018.1438223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Pseudogymnoascus destructans is the causal agent of bat white-nose syndrome (WNS), which is devastating some North American bat populations. Previous transcriptome studies provided insight regarding the molecular mechanisms involved in WNS; however, it is unclear how different environmental parameters could influence pathogenicity. This information could be useful in developing management strategies to mitigate the negative impacts of P. destructans on bats. We cultured three P. destructans isolates from Atlantic Canada on two growth media (potato dextrose agar and Sabouraud dextrose agar) that differ in their nitrogen source, and at two separate incubation temperatures (4 C and 15 C) that approximate the temperature range of bat hibernacula during the winter and a temperature within its optimal mycelial growth range. We conducted RNA sequencing to determine transcript levels in each sample and performed differential gene expression (DGE) analyses to test the influence of growth medium and incubation temperature on gene expression. We also compared our in vitro results with previous RNA-sequencing data sets generated from P. destructans growing on the wings of a susceptible host, Myotis lucifugus. Our findings point to a critical role for substrate and incubation temperature in influencing the P. destructans transcriptome. DGE analyses suggested that growth medium plays a larger role than temperature in determining P. destructans gene expression and that although the psychrophilic fungus responds to different nitrogen sources, it may have evolved for continued growth at a broad range of low temperatures. Further, our data suggest that down-regulation of the RNA-interference pathway and increased fatty acid metabolism are involved in the P. destructans-bat interaction. Finally, we speculate that to reduce the activation of host defense responses, P. destructans minimizes changes in the expression of genes encoding secreted proteins during bat colonization.
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Affiliation(s)
- Michael E Donaldson
- a Environmental and Life Sciences Graduate Program , Trent University , 2140 East Bank Drive, Peterborough , Ontario , K9L 1Z8, Canada
| | - Christina M Davy
- a Environmental and Life Sciences Graduate Program , Trent University , 2140 East Bank Drive, Peterborough , Ontario , K9L 1Z8, Canada.,b Wildlife Research and Monitoring Section , Ontario Ministry of Natural Resources and Forestry , 2140 East Bank Drive, Peterborough , Ontario , K9L 1Z8, Canada
| | - Karen J Vanderwolf
- c New Brunswick Museum , 277 Douglas Avenue, Saint John , New Brunswick , E2K 1E5, Canada.,d Department of Pathobiological Sciences , University of Wisconsin-Madison , 2015 Linden Drive, Madison , Wisconsin 53706
| | - Craig K R Willis
- e Department of Biology , University of Winnipeg , 515 Portage Avenue, Winnipeg , Manitoba , R3B 2E9, Canada
| | - Barry J Saville
- a Environmental and Life Sciences Graduate Program , Trent University , 2140 East Bank Drive, Peterborough , Ontario , K9L 1Z8, Canada.,f Forensic Science Department , Trent University , 2140 East Bank Drive, Peterborough , Ontario, K9L 1Z8 , Canada
| | - Christopher J Kyle
- a Environmental and Life Sciences Graduate Program , Trent University , 2140 East Bank Drive, Peterborough , Ontario , K9L 1Z8, Canada.,f Forensic Science Department , Trent University , 2140 East Bank Drive, Peterborough , Ontario, K9L 1Z8 , Canada
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19
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Field KA. Quantification of pathogen levels is necessary to compare responses to pathogen exposure: Comment on Davy et al. "The other white-nose syndrome transcriptome". Ecol Evol 2018; 8:5235-5237. [PMID: 29938047 PMCID: PMC6010789 DOI: 10.1002/ece3.4034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
When studying host responses to the presence of pathogens, the pathogen levels should be verified within the samples. The RNA‐Seq samples from Davy et al. (2017) do not contain detectable Pseudogymnoascus destructans pathogen levels compared to other studies. Future studies will be necessary to determine how hosts resistant to white‐nose syndrome respond differently than susceptible hosts at the whole‐transcriptome level.
![]() Linked Article: https://doi.org/10.1002/ece3.4035
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Affiliation(s)
- Kenneth A Field
- Department of Biology Bucknell University Lewisburg Pennsylvania
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20
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Donaldson ME, Davy CM, Willis CKR, McBurney S, Park A, Kyle CJ. Profiling the immunome of little brown myotis provides a yardstick for measuring the genetic response to white-nose syndrome. Evol Appl 2017; 10:1076-1090. [PMID: 29151862 PMCID: PMC5680615 DOI: 10.1111/eva.12514] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 06/26/2017] [Indexed: 12/19/2022] Open
Abstract
White‐nose syndrome (WNS) has devastated populations of hibernating bats in eastern North America, leading to emergency conservation listings for several species including the previously ubiquitous little brown myotis (Myotis lucifugus). However, some bat populations near the epicenter of the WNS panzootic appear to be stabilizing after initial precipitous declines, which could reflect a selective immunogenetic sweep. To investigate the hypothesis that WNS exerts significant selection on the immunome of affected bat populations, we developed a novel, high‐throughput sequence capture assay targeting 138 adaptive, intrinsic, and innate immunity genes of putative adaptive significance, as well as their respective regulatory regions (~370 kbp of genomic sequence/individual). We used the assay to explore baseline immunogenetic variation in M. lucifugus and to investigate whether particular immune genes/variants are associated with WNS susceptibility. We also used our assay to detect 1,038 putatively neutral single nucleotide polymorphisms and characterize contemporary population structure, providing context for the identification of local immunogenetic adaptation. Sequence capture provided a cost‐effective, “all‐in‐one” assay to test for neutral genetic and immunogenetic structure and revealed fine‐scale, baseline immunogenetic differentiation between sampling sites <600 km apart. We identified functional immunogenetic variants in M. lucifugus associated with WNS susceptibility. This study lays the foundations for future investigations of rangewide immunogenetic adaptation to WNS in M. lucifugus and provides a blueprint for studies of evolutionary rescue in other host–pathogen systems.
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Affiliation(s)
- Michael E Donaldson
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada
| | - Christina M Davy
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada.,Wildlife Research and Monitoring Section Ontario Ministry of Natural Resources and Forestry Peterborough ON Canada
| | - Craig K R Willis
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR) University of Winnipeg Winnipeg MB Canada
| | - Scott McBurney
- Canadian Wildlife Health Cooperative Atlantic Region Atlantic Veterinary College University of Prince Edward Island Charlottetown PEI Canada
| | - Allysia Park
- Canadian Wildlife Health Cooperative Atlantic Region Atlantic Veterinary College University of Prince Edward Island Charlottetown PEI Canada
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21
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Davy CM, Donaldson ME, Willis CKR, Saville BJ, McGuire LP, Mayberry H, Wilcox A, Wibbelt G, Misra V, Bollinger T, Kyle CJ. The other white-nose syndrome transcriptome: Tolerant and susceptible hosts respond differently to the pathogen Pseudogymnoascus destructans. Ecol Evol 2017; 7:7161-7170. [PMID: 28944007 PMCID: PMC5606880 DOI: 10.1002/ece3.3234] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/11/2017] [Accepted: 06/12/2017] [Indexed: 12/30/2022] Open
Abstract
Mitigation of emerging infectious diseases that threaten global biodiversity requires an understanding of critical host and pathogen responses to infection. For multihost pathogens where pathogen virulence or host susceptibility is variable, host–pathogen interactions in tolerant species may identify potential avenues for adaptive evolution in recently exposed, susceptible hosts. For example, the fungus Pseudogymnoascus destructans causes white‐nose syndrome (WNS) in hibernating bats and is responsible for catastrophic declines in some species in North America, where it was recently introduced. Bats in Europe and Asia, where the pathogen is endemic, are only mildly affected. Different environmental conditions among Nearctic and Palearctic hibernacula have been proposed as an explanation for variable disease outcomes, but this hypothesis has not been experimentally tested. We report the first controlled, experimental investigation of response to P. destructans in a tolerant, European species of bat (the greater mouse‐eared bat, Myotis myotis). We compared body condition, disease outcomes and gene expression in control (sham‐exposed) and exposed M. myotis that hibernated under controlled environmental conditions following treatment. Tolerant M. myotis experienced extremely limited fungal growth and did not exhibit symptoms of WNS. However, we detected no differential expression of genes associated with immune response in exposed bats, indicating that immune response does not drive tolerance of P. destructans in late hibernation. Variable responses to P. destructans among bat species cannot be attributed solely to environmental or ecological factors. Instead, our results implicate coevolution with the pathogen, and highlight the dynamic nature of the “white‐nose syndrome transcriptome.” Interspecific variation in response to exposure by the host (and possibly pathogen) emphasizes the importance of context in studies of the bat‐WNS system, and robust characterization of genetic responses to exposure in various hosts and the pathogen should precede any attempts to use particular bat species as generalizable “model hosts.”
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Affiliation(s)
- Christina M Davy
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada.,Department of Biology University of Winnipeg Winnipeg MB Canada.,Present address: Ontario Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section Trent University Peterborough ON Canada
| | - Michael E Donaldson
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada
| | | | - Barry J Saville
- Forensic Science Department Trent University Peterborough ON Canada
| | - Liam P McGuire
- Department of Biology University of Winnipeg Winnipeg MB Canada.,Department of Biological Sciences Texas Tech University Lubbock TX USA
| | | | - Alana Wilcox
- Department of Biology University of Winnipeg Winnipeg MB Canada
| | - Gudrun Wibbelt
- Leibniz Institute of Zoo and Wildlife Research Berlin Germany
| | - Vikram Misra
- Department of Microbiology Western College of Veterinary Medicine University of Saskatchewan Saskatoon SK Canada
| | - Trent Bollinger
- Department of Veterinary Pathology Western College of Veterinary Medicine University of Saskatchewan Saskatoon SK Canada
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22
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Mayberry HW, McGuire LP, Willis CKR. Body temperatures of hibernating little brown bats reveal pronounced behavioural activity during deep torpor and suggest a fever response during white-nose syndrome. J Comp Physiol B 2017; 188:333-343. [PMID: 28766065 DOI: 10.1007/s00360-017-1119-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 07/18/2017] [Accepted: 07/25/2017] [Indexed: 01/06/2023]
Abstract
Hibernating animals use torpor [reduced body temperature (T b) and metabolic rate] to reduce energy expenditure during winter. Periodic arousals to normal T b are energetically expensive, so hibernators trade off arousal benefits against energetic costs. This is especially important for bats with white-nose syndrome (WNS), a fungal disease causing increased arousal frequency. Little brown bats (Myotis lucifugus) with WNS show upregulation of endogenous pyrogens and sickness behaviour. Therefore, we hypothesized that WNS should cause a fever response characterized by elevated T b. Hibernators could also accrue some benefits of arousals with minimal T b increase, thus avoiding full arousal costs. We compared skin temperature (T sk) of captive Myotis lucifugus inoculated with the WNS-causing fungus to T sk of sham-inoculated controls. Infected bats re-warmed to higher T sk during arousals which is consistent with a fever response. Torpid T sk did not differ. During what we term "cold arousals", bats exhibited movement following T sk increases of only 2.2 ± 0.3 °C, compared to >20 °C increases during normal arousals. Cold arousals occurred in both infected and control bats, suggesting they are not a pathophysiological consequence of WNS. Fever responses are energetically costly and could exacerbate energy limitation and premature fat depletion for bats with WNS. Cold arousals could represent an energy-saving mechanism for both healthy and WNS-affected bats when complete arousals are unnecessary or too costly. A few cold arousals were observed mid-hibernation, typically in response to disturbances. Cold arousals may, therefore, represent a voluntary restriction of arousal temperature instead of loss of thermoregulatory control.
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Affiliation(s)
- Heather W Mayberry
- Department of Biology, University of Winnipeg, 515 Portage Ave, Winnipeg, MB, R3B 2E9, Canada. .,Department of Ecology and Evolutionary Biology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada.
| | - Liam P McGuire
- Department of Biology, University of Winnipeg, 515 Portage Ave, Winnipeg, MB, R3B 2E9, Canada.,Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
| | - Craig K R Willis
- Department of Biology, University of Winnipeg, 515 Portage Ave, Winnipeg, MB, R3B 2E9, Canada
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