GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Oxford University Press (OUP) ; 2020
    In:  Molecular Biology and Evolution Vol. 37, No. 8 ( 2020-08-01), p. 2287-2299
    In: Molecular Biology and Evolution, Oxford University Press (OUP), Vol. 37, No. 8 ( 2020-08-01), p. 2287-2299
    Abstract: Parasites are arguably among the strongest drivers of natural selection, constraining hosts to evolve resistance and tolerance mechanisms. Although, the genetic basis of adaptation to parasite infection has been widely studied, little is known about how epigenetic changes contribute to parasite resistance and eventually, adaptation. Here, we investigated the role of host DNA methylation modifications to respond to parasite infections. In a controlled infection experiment, we used the three-spined stickleback fish, a model species for host–parasite studies, and their nematode parasite Camallanus lacustris. We showed that the levels of DNA methylation are higher in infected fish. Results furthermore suggest correlations between DNA methylation and shifts in key fitness and immune traits between infected and control fish, including respiratory burst and functional trans-generational traits such as the concentration of motile sperm. We revealed that genes associated with metabolic, developmental, and regulatory processes (cell death and apoptosis) were differentially methylated between infected and control fish. Interestingly, genes such as the neuropeptide FF receptor 2 and the integrin alpha 1 as well as molecular pathways including the Th1 and Th2 cell differentiation were hypermethylated in infected fish, suggesting parasite-mediated repression mechanisms of immune responses. Altogether, we demonstrate that parasite infection contributes to genome-wide DNA methylation modifications. Our study brings novel insights into the evolution of vertebrate immunity and suggests that epigenetic mechanisms are complementary to genetic responses against parasite-mediated selection.
    Type of Medium: Online Resource
    ISSN: 0737-4038 , 1537-1719
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2020
    detail.hit.zdb_id: 2024221-9
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: PLOS Genetics, Public Library of Science (PLoS), Vol. 11, No. 7 ( 2015-7-30), p. e1005414-
    Type of Medium: Online Resource
    ISSN: 1553-7404
    Language: English
    Publisher: Public Library of Science (PLoS)
    Publication Date: 2015
    detail.hit.zdb_id: 2186725-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Ecology, Wiley, Vol. 100, No. 8 ( 2019-08)
    Abstract: Parasites can shape the structure and function of ecosystems by influencing both the density and traits of their hosts. Such changes in ecosystems are particularly likely when the host is a predator that mediates the dynamics of trophic cascades. Here, we experimentally tested how parasite load of a small predatory fish, the threespine stickleback, can affect the occurrence and strength of trophic cascades and ecosystem functioning. In a factorial mesocosm experiment, we manipulated the density of stickleback (low vs. high), and the level of parasite load (natural vs. reduced). In addition, we used two stickleback populations from different lineages: an eastern European lineage with a more pelagic phenotype (Lake Constance) and a western European lineage with a more benthic phenotype (Lake Geneva). We found that stickleback caused trophic cascades in the pelagic but not the benthic food chain. Evidence for pelagic trophic cascades was stronger in treatments where parasite load of stickleback was reduced with an antihelmintic medication, and where fish originated from Lake Constance (i.e., the more pelagic lineage). A structural equation model revealed that differences in stickleback lineage and parasite load were most likely to impact trophic cascades via changes in the composition, rather than overall biomass, of zooplankton communities. Overall, our results provide experimental evidence that parasites of predators can influence the cascading effects of fish on lower trophic levels with consequences on ecosystem functioning.
    Type of Medium: Online Resource
    ISSN: 0012-9658 , 1939-9170
    URL: Issue
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 2019
    detail.hit.zdb_id: 1797-8
    detail.hit.zdb_id: 2010140-5
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Evolution, Wiley, Vol. 67, No. 8 ( 2013-08), p. 2400-2412
    Type of Medium: Online Resource
    ISSN: 0014-3820
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 2013
    detail.hit.zdb_id: 2036375-8
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    Wiley ; 2014
    In:  Ecology and Evolution Vol. 4, No. 12 ( 2014-06), p. 2488-2504
    In: Ecology and Evolution, Wiley, Vol. 4, No. 12 ( 2014-06), p. 2488-2504
    Abstract: Repeated recolonization of freshwater environments following Pleistocene glaciations has played a major role in the evolution and adaptation of anadromous taxa. Located at the western fringe of Europe, Ireland and Britain were likely recolonized rapidly by anadromous fishes from the North Atlantic following the last glacial maximum ( LGM ). While the presence of unique mitochondrial haplotypes in Ireland suggests that a cryptic northern refugium may have played a role in recolonization, no explicit test of this hypothesis has been conducted. The three‐spined stickleback is native and ubiquitous to aquatic ecosystems throughout Ireland, making it an excellent model species with which to examine the biogeographical history of anadromous fishes in the region. We used mitochondrial and microsatellite markers to examine the presence of divergent evolutionary lineages and to assess broad‐scale patterns of geographical clustering among postglacially isolated populations. Our results confirm that Ireland is a region of secondary contact for divergent mitochondrial lineages and that endemic haplotypes occur in populations in Central and Southern Ireland. To test whether a putative Irish lineage arose from a cryptic Irish refugium, we used approximate Bayesian computation ( ABC ). However, we found no support for this hypothesis. Instead, the Irish lineage likely diverged from the European lineage as a result of postglacial isolation of freshwater populations by rising sea levels. These findings emphasize the need to rigorously test biogeographical hypothesis and contribute further evidence that postglacial processes may have shaped genetic diversity in temperate fauna.
    Type of Medium: Online Resource
    ISSN: 2045-7758 , 2045-7758
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2014
    detail.hit.zdb_id: 2635675-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Online Resource
    Online Resource
    Wiley ; 2016
    In:  Ecology and Evolution Vol. 6, No. 15 ( 2016-08), p. 5305-5320
    In: Ecology and Evolution, Wiley, Vol. 6, No. 15 ( 2016-08), p. 5305-5320
    Abstract: Using evolutionary theory to predict the dynamics of populations is one of the aims of evolutionary conservation. In endangered species, with geographic range extending over continuous areas, the predictive capacity of evolutionary‐based conservation measures greatly depends on the accurate identification of reproductive units. The endangered European eel ( Anguilla anguilla ) is a highly migratory fish species with declining population due to a steep recruitment collapse in the beginning of the 1980s. Despite punctual observations of genetic structure, the population is viewed as a single panmictic reproductive unit. To understand the possible origin of the detected structure in this species, we used a combination of mitochondrial and nuclear loci to indirectly evaluate the possible existence of cryptic demes. For that, 403 glass eels from three successive cohorts arriving at a single location were screened for phenotypic and genetic diversity, while controlling for possible geographic variation. Over the 3 years of sampling, we consistently identified three major matrilines which we hypothesized to represent demes. Interestingly, not only we found that population genetic models support the existence of those matriline‐driven demes over a completely panmictic mode of reproduction, but also we found evidence for asymmetric gene flow amongst those demes. We uphold the suggestion that the detection of demes related to those matrilines reflect a fragmented spawning ground, a conceptually plausible consequence of the low abundance that the European eel has been experiencing for three decades. Furthermore, we suggest that this cryptic organization may contribute to the maintenance of the adaptive potential of the species.
    Type of Medium: Online Resource
    ISSN: 2045-7758 , 2045-7758
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2016
    detail.hit.zdb_id: 2635675-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    In: Marine Biology, Springer Science and Business Media LLC, Vol. 166, No. 10 ( 2019-10)
    Abstract: As biodiversity worldwide is decreasing, to preserve adaptive potential, the importance of maintaining species’ genetic and trait diversities is increasing. An efficient foraging strategy is a critical trait for an organism’s fitness, as it affects its physiology and reproduction. Understanding such strategies is especially relevant for species with long feeding migrations such as sea turtles. Using carbon and nitrogen stable isotopes combined with mitochondrial sequencing, we explored the diversity of feeding strategies in genetically differentiated nesting groups of loggerhead sea turtles ( Caretta caretta ) within the Cape Verde Archipelago. Here, we reveal a pattern where turtles from most islands use two distinct oceanic feeding strategies, including one putatively linked to a 15 N-enriched zone of the West African upwelling area. On the Eastern island of Boavista, an additional third strategy exists used by turtles feeding mostly neritically. Contrary to previous paradoxical assumptions, oceanic turtles, that represent the vast majority of the population, are not smaller than neritic turtles and therefore do not seem to feed in a suboptimal environment. Our results also suggest that the number of feeding strategies may correlate with demography, whereby a greater feeding strategy diversity matches demographic signs of recent expansion after a population bottleneck for turtles nesting on the island of Boavista. Overall, the feeding ecology of Cape Verde loggerhead turtles is complex and likely shaped by an interaction between environmental and population parameters. Our results stress the importance of conservation efforts to prevent loss of critical diversity in endangered species.
    Type of Medium: Online Resource
    ISSN: 0025-3162 , 1432-1793
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2019
    detail.hit.zdb_id: 1117-4
    detail.hit.zdb_id: 1459413-4
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Online Resource
    Online Resource
    Springer Science and Business Media LLC ; 2011
    In:  BMC Developmental Biology Vol. 11, No. 1 ( 2011-09-12)
    In: BMC Developmental Biology, Springer Science and Business Media LLC, Vol. 11, No. 1 ( 2011-09-12)
    Abstract: Rapid advances in genomics have provided nearly complete genome sequences for many different species. However, no matter how the sequencing technology has improved, natural genetic polymorphism complicates the production of high quality reference genomes. To address this problem, researchers have tried using artificial modes of genome manipulation such as gynogenesis for fast production of inbred lines. Results Here, we present the first successful induction of diploid gynogenesis in an evolutionary model system, the three-spined sticklebacks ( Gasterosteus aculeatus ), using a combination of UV-irradiation of the sperm and heat shock (HS) of the resulting embryo to inhibit the second meiotic division. Optimal UV irradiation of the sperm was established by exposing stickleback sperm to a UV- light source at various times. Heat shock parameters like temperature, duration, and time of initiation were tested by subjecting eggs fertilized with UV inactivated sperm 5, 10, 15, 20, 25, or 30 minutes post fertilization (mpf) to 30°C, 34°C, or 38°C for 2, 4, 6 or 8 minutes. Gynogen yield was highest when stickleback eggs were activated with 2 minutes UV-irradiated sperm and received HS 5 mpf at 34°C for 4 minutes. Conclusions Diploid gynogenesis has been successfully performed in three-spined stickleback. This has been confirmed by microsatellite DNA analysis which revealed exclusively maternal inheritance in all gynogenetic fry tested. Ploidy verification by flow cytometry showed that gynogenetic embryos/larvae exhibiting abnormalities were haploids and those that developed normally were diploids, i.e., double haploids that can be raised until adult size.
    Type of Medium: Online Resource
    ISSN: 1471-213X
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2011
    detail.hit.zdb_id: 2041492-4
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Journal of Animal Ecology, Wiley, Vol. 88, No. 12 ( 2019-12), p. 1986-1997
    Abstract: Parasites are important selective agents with the potential to limit gene flow between host populations by shaping local host immunocompetence. We report on a contact zone between lake and river three‐spined sticklebacks ( Gasterosteus aculeatus ) that offers the ideal biogeographic setting to explore the role of parasite‐mediated selection on reproductive isolation. A waterfall acts as a natural barrier and enforces unidirectional migration from the upstream river stickleback population to the downstream river and lake populations. We assessed population genetic structure and parasite communities over four years. In a set of controlled experimental infections, we compared parasite susceptibility of upstream and downstream fish by exposing laboratory‐bred upstream river and lake fish, as well as hybrids, to two common lake parasite species: a generalist trematode parasite, Diplostomum pseudospathaceum , and a host‐specific cestode, Schistocephalus solidus . We found consistent genetic differentiation between upstream and downstream populations across four sampling years, even though the downstream river consisted of ~10% first‐generation migrants from the upstream population as detected by parentage analysis. Fish in the upstream population had lower genetic diversity and were strikingly devoid of macroparasites. Through experimental infections, we demonstrated that upstream fish and their hybrids had higher susceptibility to parasite infections than downstream fish. Despite this, naturally sampled upstream migrants were less infected than downstream residents. Thus, migrants coming from a parasite‐free environment may enjoy an initial fitness advantage, but their descendants seem likely to suffer from higher parasite loads. Our results suggest that adaptation to distinct parasite communities can influence stickleback invasion success and may represent a barrier to gene flow, even between close and connected populations.
    Type of Medium: Online Resource
    ISSN: 0021-8790 , 1365-2656
    URL: Issue
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 2019
    detail.hit.zdb_id: 2006616-8
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    Elsevier BV ; 2016
    In:  Current Biology Vol. 26, No. 18 ( 2016-09), p. R853-R855
    In: Current Biology, Elsevier BV, Vol. 26, No. 18 ( 2016-09), p. R853-R855
    Type of Medium: Online Resource
    ISSN: 0960-9822
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2016
    detail.hit.zdb_id: 2019214-9
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...