1
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Dziuba MK, McIntire KM, Seto K, Davenport ES, Rogalski MA, Gowler CD, Baird E, Vaandrager M, Huerta C, Jaye R, Corcoran FE, Withrow A, Ahrendt S, Salamov A, Nolan M, Tejomurthula S, Barry K, Grigoriev IV, James TY, Duffy MA. Phylogeny, morphology, virulence, ecology, and host range of Ordospora pajunii (Ordosporidae), a microsporidian symbiont of Daphnia spp. mBio 2024; 15:e0058224. [PMID: 38651867 DOI: 10.1128/mbio.00582-24] [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: 02/27/2024] [Accepted: 03/20/2024] [Indexed: 04/25/2024] Open
Abstract
The impacts of microsporidia on host individuals are frequently subtle and can be context dependent. A key example of the latter comes from a recently discovered microsporidian symbiont of Daphnia, the net impact of which was found to shift from negative to positive based on environmental context. Given this, we hypothesized low baseline virulence of the microsporidian; here, we investigated the impact of infection on hosts in controlled conditions and the absence of other stressors. We also investigated its phylogenetic position, ecology, and host range. The genetic data indicate that the symbiont is Ordospora pajunii, a newly described microsporidian parasite of Daphnia. We show that O. pajunii infection damages the gut, causing infected epithelial cells to lose microvilli and then rupture. The prevalence of this microsporidian could be high (up to 100% in the lab and 77% of adults in the field). Its overall virulence was low in most cases, but some genotypes suffered reduced survival and/or reproduction. Susceptibility and virulence were strongly host-genotype dependent. We found that North American O. pajunii were able to infect multiple Daphnia species, including the European species Daphnia longispina, as well as Ceriodaphnia spp. Given the low, often undetectable virulence of this microsporidian and potentially far-reaching consequences of infections for the host when interacting with other pathogens or food, this Daphnia-O. pajunii symbiosis emerges as a valuable system for studying the mechanisms of context-dependent shifts between mutualism and parasitism, as well as for understanding how symbionts might alter host interactions with resources. IMPORTANCE The net outcome of symbiosis depends on the costs and benefits to each partner. Those can be context dependent, driving the potential for an interaction to change between parasitism and mutualism. Understanding the baseline fitness impact in an interaction can help us understand those shifts; for an organism that is generally parasitic, it should be easier for it to become a mutualist if its baseline virulence is relatively low. Recently, a microsporidian was found to become beneficial to its Daphnia hosts in certain ecological contexts, but little was known about the symbiont (including its species identity). Here, we identify it as the microsporidium Ordospora pajunii. Despite the parasitic nature of microsporidia, we found O. pajunii to be, at most, mildly virulent; this helps explain why it can shift toward mutualism in certain ecological contexts and helps establish O. pajunii is a valuable model for investigating shifts along the mutualism-parasitism continuum.
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Affiliation(s)
- Marcin K Dziuba
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kristina M McIntire
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kensuke Seto
- Faculty of Environment and Information Sciences, Yokohama National University, Yokohama, Kanagawa, Japan
| | - Elizabeth S Davenport
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Mary A Rogalski
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
- Biology Department, Bowdoin College, Brunswick, Maine, USA
| | - Camden D Gowler
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Emma Baird
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Megan Vaandrager
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Cristian Huerta
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Riley Jaye
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Fiona E Corcoran
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Alicia Withrow
- Center for Advanced Microscopy, Michigan State University, East Lansing, Michigan, USA
| | - Steven Ahrendt
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Asaf Salamov
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Matt Nolan
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Sravanthi Tejomurthula
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Kerrie Barry
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Igor V Grigoriev
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, California, USA
| | - Timothy Y James
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Meghan A Duffy
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
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2
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Shaw CL, Bilich R, Duffy MA. A common multi-host parasite shows genetic structuring at the host species and population levels. Parasitology 2024:1-10. [PMID: 38616414 DOI: 10.1017/s0031182024000428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Although individual parasite species commonly infect many populations across physical space as well as multiple host species, the extent to which parasites traverse physical and phylogenetic distances is unclear. Population genetic analyses of parasite populations can reveal how parasites move across space or between host species, including helping assess whether a parasite is more likely to infect a different host species in the same location or the same host species in a different location. Identifying these transmission barriers could be exploited for effective disease control. Here, we analysed population genetic structuring of the parasite Pasteuria ramosa in daphniid host species from different lakes. Outbreaks occurred most often in the common host species Daphnia dentifera and Daphnia retrocurva. The genetic distance between parasite samples tended to be smaller when samples were collected from the same lake, the same host species and closer in time. Within lakes, the parasite showed structure by host species and sampling date; within a host species, the parasite showed structure by lake and sampling date. However, despite this structuring, we found the same parasite genotype infecting closely related host species, and we sometimes found the same genotype in nearby lakes. Thus, P. ramosa experiences challenges infecting different host species and moving between populations, but doing so is possible. In addition, the structuring by sampling date indicates potential adaptation to or coevolution with host populations and supports prior findings that parasite population structure is dynamic during outbreaks.
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Affiliation(s)
- Clara L Shaw
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
- Department of Biology, University of Minnesota Duluth, Duluth, MN, USA
| | - Rebecca Bilich
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Meghan A Duffy
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
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3
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Fearon ML, Gowler CD, Duffy MA. Inconsistent dilution: experimental but not field evidence for a dilution effect in Daphnia-bacteria interactions. Oecologia 2024; 204:351-363. [PMID: 38105355 DOI: 10.1007/s00442-023-05486-8] [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: 02/07/2023] [Accepted: 11/14/2023] [Indexed: 12/19/2023]
Abstract
The dilution effect hypothesis, which suggests greater host biodiversity can reduce infectious disease transmission, occurs in many systems but is not universal. Most studies only investigate the dilution of a single parasite in a community, but many host communities have multiple parasites circulating. We studied a zooplankton host community with prior support for a dilution effect in laboratory- and field-based studies of a fungal parasite, Metschnikowia bicuspidata. We used paired experiments and field studies to ask whether dilution also occurred for a bacterial parasite, Pasteuria ramosa. We hypothesized that the similarities between the parasites might mean the dilution pattern seen in Metschnikowia would also be seen in Pasteuria. However, because Daphnia-Pasteuria interactions have strong host-parasite genotype specificity, dilution may be less likely if diluter host genotypes vary in their capacity to dilute Pasteuria. In a lab experiment, Pasteuria prevalence in susceptible Daphnia dentifera was reduced strongly by higher densities of D. pulicaria and marginally by higher densities of D. retrocurva. In a second experiment, different D. pulicaria genotypes had a similar capacity to dilute both Metschnikowia and Pasteuria, suggesting that Pasteuria's strong host-parasite genotype specificity should not prevent dilution. However, we found no evidence of an impact of the dilution effect on the size of Pasteuria epidemics in D. dentifera in Midwestern U.S. lakes. Our finding that a second parasite infecting the same host community does not show a similar dilution effect in the field suggests the impact of biodiversity can differ even among parasites in the same host community.
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Affiliation(s)
- Michelle L Fearon
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Camden D Gowler
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Meghan A Duffy
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
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4
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Shaw CL, Duffy MA. Rapid evolution of a bacterial parasite during outbreaks in two Daphnia populations. Ecol Evol 2023; 13:e9676. [PMID: 36694542 PMCID: PMC9843074 DOI: 10.1002/ece3.9676] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/09/2022] [Accepted: 12/10/2022] [Indexed: 01/18/2023] Open
Abstract
Myriad ecological and evolutionary factors can influence whether a particular parasite successfully transmits to a new host during a disease outbreak, with consequences for the structure and diversity of parasite populations. However, even though the diversity and evolution of parasite populations are of clear fundamental and applied importance, we have surprisingly few studies that track how genetic structure of parasites changes during naturally occurring outbreaks in non-human populations. Here, we used population genetic approaches to reveal how genotypes of a bacterial parasite, Pasteuria ramosa, change over time, focusing on how infecting P. ramosa genotypes change during the course of epidemics in Daphnia populations in two lakes. We found evidence for genetic change - and, therefore, evolution - of the parasite during outbreaks. In one lake, P. ramosa genotypes were structured by sampling date; in both lakes, genetic distance between groups of P. ramosa isolates increased with time between sampling. Diversity in parasite populations remained constant over epidemics, although one epidemic (which was large) had low genetic diversity while the other epidemic (which was small) had high genetic diversity. Our findings demonstrate that patterns of parasite evolution differ between outbreaks; future studies exploring the feedbacks among epidemic size, host diversity, and parasite genetic diversity would improve our understanding of parasite dynamics and evolution.
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Affiliation(s)
- Clara L. Shaw
- Department of Ecology & Evolutionary BiologyUniversity of MichiganAnn ArborMichiganUSA,Department of BiologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Meghan A. Duffy
- Department of Ecology & Evolutionary BiologyUniversity of MichiganAnn ArborMichiganUSA
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5
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Fredericksen M, Ameline C, Krebs M, Hüssy B, Fields PD, Andras JP, Ebert D. Infection phenotypes of a coevolving parasite are highly diverse, structured, and specific. Evolution 2021; 75:2540-2554. [PMID: 34431523 PMCID: PMC9290032 DOI: 10.1111/evo.14323] [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: 03/13/2021] [Revised: 06/30/2021] [Accepted: 07/26/2021] [Indexed: 12/27/2022]
Abstract
Understanding how diversity is maintained in natural populations is a major goal of evolutionary biology. In coevolving hosts and parasites, negative frequency-dependent selection is one mechanism predicted to maintain genetic variation. While much is known about host diversity, parasite diversity remains understudied in coevolutionary research. Here, we survey natural diversity in a bacterial parasite by characterizing infection phenotypes for over 50 isolates in relation to 12 genotypes of their host, Daphnia magna. We find striking phenotypic variation among parasite isolates, and we discover the parasite can infect its host through at least five different attachment sites. Variation in attachment success at each site is explained to varying degrees by host and parasite genotypes. A spatial correlation analysis showed that infectivity of different isolates does not correlate with geographic distance, meaning isolates from widespread populations are equally able to infect the host. Overall, our results reveal that infection phenotypes of this parasite are highly diverse. Our results are consistent with the prediction that under Red Queen coevolutionary dynamics both the host and the parasite should show high genetic diversity for traits of functional importance in their interactions.
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Affiliation(s)
- Maridel Fredericksen
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
| | - Camille Ameline
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
| | - Michelle Krebs
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
| | - Benjamin Hüssy
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
| | - Jason P Andras
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland.,Department of Biological Sciences, Clapp Laboratory, Mount Holyoke College, South Hadley, Massachusetts
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, CH-4051, Switzerland
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6
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Izhar R, Gilboa C, Ben‐Ami F. Disentangling the steps of the infection process responsible for juvenile disease susceptibility. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13580] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rony Izhar
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
| | - Chen Gilboa
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
| | - Frida Ben‐Ami
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
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7
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Andras JP, Fields PD, Ebert D. Spatial population genetic structure of a bacterial parasite in close coevolution with its host. Mol Ecol 2018; 27:1371-1384. [DOI: 10.1111/mec.14545] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Jason P. Andras
- Department of Biological Sciences; Clapp Laboratory; Mount Holyoke College; South Hadley MA USA
| | - Peter D. Fields
- Department of Environmental Sciences - Zoology; University of Basel; Basel Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences - Zoology; University of Basel; Basel Switzerland
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8
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Auld SKJR, Searle CL, Duffy MA. Parasite transmission in a natural multihost-multiparasite community. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0097. [PMID: 28289264 DOI: 10.1098/rstb.2016.0097] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2016] [Indexed: 11/12/2022] Open
Abstract
Understanding the transmission and dynamics of infectious diseases in natural communities requires understanding the extent to which the ecology, evolution and epidemiology of those diseases are shaped by alternative hosts. We performed laboratory experiments to test how parasite spillover affected traits associated with transmission in two co-occurring parasites: the bacterium Pasteuria ramosa and the fungus Metschnikowia bicuspidata Both parasites were capable of transmission from the reservoir host (Daphnia dentifera) to the spillover host (Ceriodaphnia dubia), but this occurred at a much higher rate for the fungus than the bacterium. We quantified transmission potential by combining information on parasite transmission and growth rate, and used this to compare parasite fitness in the two host species. For both parasites, transmission potential was lower in the spillover host. For the bacterium, virulence was higher in the spillover host. Transmission back to the original host was high for both parasites, with spillover influencing transmission rate of the fungus but not the bacterium. Thus, while inferior, the spillover host is not a dead-end for either parasite. Overall, our results demonstrate that the presence of multiple hosts in a community can have important consequences for disease transmission, and host and parasite fitness.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'.
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Affiliation(s)
- Stuart K J R Auld
- Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK
| | - Catherine L Searle
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Meghan A Duffy
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA
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9
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Schenk H, Traulsen A, Gokhale CS. Chaotic provinces in the kingdom of the Red Queen. J Theor Biol 2017; 431:1-10. [PMID: 28757073 DOI: 10.1016/j.jtbi.2017.07.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 04/11/2017] [Accepted: 07/26/2017] [Indexed: 11/29/2022]
Abstract
The interplay between parasites and their hosts is found in all kinds of species and plays an important role in understanding the principles of evolution and coevolution. Usually, the different genotypes of hosts and parasites oscillate in their abundances. The well-established theory of oscillatory Red Queen dynamics proposes an ongoing change in frequencies of the different types within each species. So far, it is unclear under what conditions Red Queen dynamics persists, especially when the number of types per species increases. Some models show that with many types of hosts and parasites or more species chaotic dynamics occur. In our analysis, an arbitrary number of types within two species are examined in a deterministic framework with constant or changing population size and very simple interactions. This general framework allows for analytical solutions for internal fixed points and their stability. The numerical analysis shows that for two species, once more than two types are considered per species, irregular dynamics in their frequencies can be observed in the long run. The nature of the dynamics depends strongly on the initial configuration of the system; the usual regular Red Queen oscillations are only observed when all types initially have similar abundance.
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Affiliation(s)
- Hanna Schenk
- Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, August-Thienemann Str-2, Plön, 24306, Germany
| | - Arne Traulsen
- Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, August-Thienemann Str-2, Plön, 24306, Germany
| | - Chaitanya S Gokhale
- Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, August-Thienemann Str-2, Plön, 24306, Germany; New Zealand Institute for Advanced Study, Massey University, Albany, Private Bag 102904, North Shore Mail Centre, Auckland, 0745, New Zealand.
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10
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Bourgeois Y, Roulin AC, Müller K, Ebert D. Parasitism drives host genome evolution: Insights from thePasteuria ramosa-Daphnia magnasystem. Evolution 2017; 71:1106-1113. [DOI: 10.1111/evo.13209] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 02/16/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Yann Bourgeois
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Anne C. Roulin
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Institute of Plant and Microbial Biology; Zollikerstrasse 107 8008 Zürich Switzerland
| | - Kristina Müller
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Dieter Ebert
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
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11
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Birnbaum SSL, Gerardo NM. Patterns of Specificity of the Pathogen Escovopsis across the Fungus-Growing Ant Symbiosis. Am Nat 2016; 188:52-65. [PMID: 27322121 DOI: 10.1086/686911] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Parasites evolve within complex abiotic and biotic environments. Because of this, it is often challenging to ascertain how evolutionary and ecological processes together affect parasite specialization. Here, we use the fungus-growing ant system, which consists of ancient, likely coevolved, complex communities, to explore the ecological and evolutionary forces shaping host-parasite specificity. We use a comparative phylogenetic framework to determine whether patterns of specificity between the fungal parasite Escovopsis and its host fungi at fine phylogenetic scales reflect patterns of specificity at broader phylogenetic levels. In other words, we ask whether parasite specificity across broad host phylogenetic relationships is maintained by specificity toward more closely related hosts. We couple this exploration with manipulations of the community context within which host-parasite interactions are taking place to evaluate how community complexity alters parasite specificity. Regardless of host community complexity, parasites displayed a consistent pattern of specialization on native hosts, that is, those that they are found attacking in nature, with the potential for occasional switching to hosts distantly related to their native hosts. These results suggest that, even within a complex community context, pairwise host and parasite adaptation and coadaptation can be the primary drivers of the evolution and maintenance of parasite specificity.
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12
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Ebert D, Duneau D, Hall MD, Luijckx P, Andras JP, Du Pasquier L, Ben-Ami F. A Population Biology Perspective on the Stepwise Infection Process of the Bacterial Pathogen Pasteuria ramosa in Daphnia. ADVANCES IN PARASITOLOGY 2015; 91:265-310. [PMID: 27015951 DOI: 10.1016/bs.apar.2015.10.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The infection process of many diseases can be divided into series of steps, each one required to successfully complete the parasite's life and transmission cycle. This approach often reveals that the complex phenomenon of infection is composed of a series of more simple mechanisms. Here we demonstrate that a population biology approach, which takes into consideration the natural genetic and environmental variation at each step, can greatly aid our understanding of the evolutionary processes shaping disease traits. We focus in this review on the biology of the bacterial parasite Pasteuria ramosa and its aquatic crustacean host Daphnia, a model system for the evolutionary ecology of infectious disease. Our analysis reveals tremendous differences in the degree to which the environment, host genetics, parasite genetics and their interactions contribute to the expression of disease traits at each of seven different steps. This allows us to predict which steps may respond most readily to selection and which steps are evolutionarily constrained by an absence of variation. We show that the ability of Pasteuria to attach to the host's cuticle (attachment step) stands out as being strongly influenced by the interaction of host and parasite genotypes, but not by environmental factors, making it the prime candidate for coevolutionary interactions. Furthermore, the stepwise approach helps us understanding the evolution of resistance, virulence and host ranges. The population biological approach introduced here is a versatile tool that can be easily transferred to other systems of infectious disease.
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Affiliation(s)
- Dieter Ebert
- Zoological Institute, University of Basel, Basel, Switzerland
| | - David Duneau
- Zoological Institute, University of Basel, Basel, Switzerland; Department Ecologie et Diversité Biologique, University Paul Sabatier-Toulouse III, Toulouse, France
| | - Matthew D Hall
- Zoological Institute, University of Basel, Basel, Switzerland; Monash University, School of Biological Sciences, Clayton Campus, Melbourne, VIC, Australia
| | - Pepijn Luijckx
- Zoological Institute, University of Basel, Basel, Switzerland; Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Jason P Andras
- Zoological Institute, University of Basel, Basel, Switzerland; Department of Biological Sciences, Mount Holyoke College, South Hadley, MA, USA
| | | | - Frida Ben-Ami
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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13
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Lange B, Kaufmann AP, Ebert D. Genetic, ecological and geographic covariables explaining host range and specificity of a microsporidian parasite. J Anim Ecol 2015; 84:1711-9. [DOI: 10.1111/1365-2656.12421] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/24/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Benjamin Lange
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Andrea Patricia Kaufmann
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Tvärminne Zoological Station; Hanko FI-10900 Finland
| | - Dieter Ebert
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Tvärminne Zoological Station; Hanko FI-10900 Finland
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