| 1. |
- Carney Almroth, Bethanie, 1974, et al.
(författare)
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Gender differences in health and aging of Atlantic cod subject to size selective fishery
- 2012
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Ingår i: Biology Open. - : The Company of Biologists. - 2046-6390. ; 1:9, s. 922-928
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Tidskriftsartikel (refereegranskat)abstract
- We have analyzed health and physiological aging parameters in male and female Atlantic cod, Gadus morhua, captured in Kattegat, Skagerrak and in Öresund. Gender differences were clearly evident in a number of variables. Males had longer liver telomeres and higher catalase activities than females, while females had higher superoxide dismutase activity, liver somatic index and condition factor. Effects of age were found for males where levels of the antioxidant glutathione and telomere length declined with age, indicating physiological aging. Liver somatic index increased and percentage oxidized glutathione decreased with age. Between-site comparisons of males show that percentage oxidized glutathione and catalase were lowest in Kattegat, whereas protein carbonyls and condition factor were higher in Skagerrak. Females, on the other hand, showed no differences between sites or indications of somatic aging or age-related effects in egg quality, indicating that older and larger female cod are healthy and show no changes in eggs with age. In contrast, males showed indications of physiological aging and lower condition than females. The results emphasize the importance of conserving old mature fish, in particular high egg-productive females, when managing fisheries.
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| 2. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Stem Cells in Asexual Reproduction of Marine Invertebrates
- 2009
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Ingår i: Stem Cells in Marine Organisms. - Netherlands : Springer. - 9789048127665 ; , s. 105-137
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- While sexual reproduction is conserved and almost ubiquitous, asexual reproduction in forms of parthenogenesis or agametic cloning from somatic tissue is less conserved. The phylogeny shows that agametic cloning is widespread but scattered with many different modes for asexual formation of a new animal. This suggests that independent forms of cloning have evolved later from sexual ancestors between and within different phyla. Here, we present an overview of agametic cloning in the marine animal kingdom and discuss molecular and evolutionary aspects of somatic stem cell usage for asexual cloning. The molecular tissue characterizations and the relative role of different stem cells involved in agametic cloning are only at its beginning with whole phyla largely uncovered. An emerging hypothesis is that the first somatic stem cells used in cloning were also able to form a germ-line and that the more limited lineage specific stem cells are derived. We discuss advantages and problems with agametic cloning from somatic tissue and propose that the levels of stem cell potential held in the tissue can have large consequences for the reproductive life cycle strategies and long-term fitness in clonal animals and strains. We finally describe suitable molecular experimental approaches for future research on this topic.
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| 3. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Telomerase deficiency in a colonial ascidian after prolonged asexual propagation
- 2011
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Ingår i: Journal of experimental zoology B (Mol Dev Evol). ; 314B
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT In organisms that propagate by agametic cloning, the parental body is the reproductive unit and fitness increases with clonal size, so that colonial metazoans, despite lack of experimental data, have been considered potentially immortal. Using asexual propagation rate as a measure of somatic performance, and telomerase activity and relative telomere length as molecular markers of senescence, old (7-12 yr) asexual strains of a colonial ascidian, Diplosoma listerianum, were compared with their recent sexually produced progeny. We report for the first time evidence for long-term molecular senescence in asexual lineages of a metazoan, and that only passage between sexual generations provides total rejuvenation permitting indefinite propagation and growth. Thus, this colonial ascidian has not fully escaped ageing. The possibility of somatic replicative senescence also potentially helps to explain why metazoans with the capacity for asexual propagation through gametic cloning commonly undergo cycles of sexual reproduction in the wild.
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| 4. |
- Thorndyke, Michael C., 1946, et al.
(författare)
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Marine ecological genomics: when genomics meets marine ecology
- 2007
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Ingår i: Marine Ecology Progress Series. - 0171-8630. ; 332, s. 257-273
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Tidskriftsartikel (refereegranskat)abstract
- Genomics, proteomics and metabolomics (the ’omic’ technologies) have revolutionized the way we work and are able to think about working, and have opened up hitherto unimagined opportunities in all research fields. In marine ecology, while ‘standard’ molecular and genetic approaches are well known, the newer technologies are taking longer to make an impact. In this review we explore the potential and promise offered by genomics, genome technologies, expressed sequence tag (EST) collections, microarrays, proteomics and bar coding for modern marine ecology. Methods are succinctly presented with both benefits and limitations discussed. Through examples from the literature, we show how these tools can be used to answer fundamental ecological questions, e.g. ‘what is the relationship between community structure and ecological function in ecosystems?’; ‘how can a species and the phylogenetic relationship between taxa be identified?’; ‘what are the factors responsible for the limits of the ecological niche?’; or ‘what explains the variations in life-history patterns among species?’ The impact of ecological ideas and concepts on genomic science is also discussed.
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| 5. |
- Andersson, Tony, 1973-, et al.
(författare)
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Phosphoinositide 3-kinase is involved in Xenopus and Labrus melanophore aggregation
- 2003
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Ingår i: Cellular Signalling. - 0898-6568 .- 1873-3913. ; 15:12, s. 1119-1127
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Tidskriftsartikel (refereegranskat)abstract
- Melanophores are pigmented cells capable of quick colour changes through coordinated transport of their intracellular pigment granules. We demonstrate the involvement of phosphoinositide 3-kinase (PI3-K) in Xenopus and Labrus aggregation by the use of the PI3-K inhibitor, LY-294002. In Xenopus, wortmannin-insensitive PI3-K was found to be essential for the aggregation, mitogen-activated protein kinase (MAPK) activation and tyrosine phosphorylation of a 280-kDa protein, and for the maintenance of low cyclic adenosine 3':5'-monophosphate (cAMP) during the aggregated state. Pre-aggregated cells disperse completely to LY-294002 at 50-100 muM, involving a transient elevation in cAMP due to adenylate cyclase (AC) stimulation or to inhibition of cyclic nucleotide phosphodiesterase (PDE). The inactive analogue LY-303511 did not induce dispersion at the same concentrations. PDE4 and/or PDE2 was found to be involved in melanosome aggregation. The similar kinetics of LY-294002 and various PDE inhibitors indicates that the elevation of cAMP might be due to inhibition of PDE. In Labrus melanophores, LY-294002 had a less dramatic effect, probably due to less dependence on PDE in regulation of cAMP levels. In Xenopus aggregation, we suggest that melatonin stimulation of the Mel1c receptor via G(betagamma) activates PI3-K that, directly or indirectly via MAPK, activates PDE. (C) 2003 Elsevier Inc. All rights reserved.
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| 6. |
- Aspengren, Sara, 1977, et al.
(författare)
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Different strategies for color change
- 2009
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Ingår i: Cellular and Molecular Life Sciences (CMLS). - : Springer Science and Business Media LLC. - 1420-682X .- 1420-9071. ; 66, s. 187-191
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Forskningsöversikt (refereegranskat)
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| 7. |
- Aspengren, Sara, 1977, et al.
(författare)
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New Insights into Melanosome Transport in Vertebrate Pigment Cells
- 2008
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Ingår i: INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY, Vol 272 (edited by Kwang W. Jeon). - : Elsevier. - 9780123747471 ; 272, s. 245-302
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Pigment cells of lower vertebrates provide an excellent model to study organelle transport as they specialize in the translocation of pigment granules in response to defined chemical cues. This review will focus on the well-studied melanophore/melanocyte systems in fish, amphibians, and mammals. We will describe the roles of melanin, melanophores, and melanocytes in animals, current views on how the three motor proteins dynein, kinesin, and myosin-V are involved in melanosome transport along microtubules and actin filaments, and how signal transduction pathways regulate the activities of the motors to achieve aggregation and dispersion of melanosomes. We will also describe how melanosomes are transferred to surrounding skin cells in amphibians and mammals. Comparative studies have revealed that the ability of physiological color change is lost during evolution while the importance of morphological color change, mainly via transfer of pigment to surrounding skin cells, increases. In humans, pigment mainly has a role in protection against ultraviolet radiation, but also perhaps in the immune system.
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| 8. |
- Aspengren, Sara, 1977, et al.
(författare)
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Noradrenaline- and melatonin-mediated regulation of pigment aggregation in fish melanophores
- 2003
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Ingår i: Pigment Cell Research. - : Wiley. - 0893-5785. ; 16:1, s. 59-64
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Tidskriftsartikel (refereegranskat)abstract
- The effects of melatonin and noradrenaline (NA) on bi-directional melanosome transport were analysed in primary cultures of melanophores from the Atlantic cod. Both agents mediated rapid melanosome aggregation, and by using receptor antagonists, melatonin was found to bind to a melatonin receptor whereas NA binds to an α2-adrenoceptor. It has previously been stated that melatonin-mediated melanosome aggregation in Xenopus is coupled with tyrosine phosphorylation of a so far unidentified high molecular weight protein and we show that although acting through different receptors and through somewhat different downstream signalling events, tyrosine phosphorylation is of the utmost importance for melanosome aggregation mediated by both NA and melatonin in cod melanophores. Together with cyclic adenosine 3-phosphate-fluctuations, tyrosine phosphorylation functions as a switch signal for melanosome aggregation and dispersion in these cells.
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| 9. |
- Cortesi, F., et al.
(författare)
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Phenotypic Plasticity Confers Multiple Fitness Benefits to a Mimic
- 2015
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Ingår i: Current Biology. - : Elsevier BV. - 0960-9822. ; 25:7, s. 949-954
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Tidskriftsartikel (refereegranskat)abstract
- Animal communication is often deceptive; however, such dishonesty can become ineffective if it is used too often, is used out of context, or is too easy to detect [1-3]. Mimicry is a common form of deception, and most mimics gain the greatest fitness benefits when they are rare compared to their models [3, 4]. If mimics are encountered too frequently or if their model is absent, avoidance learning of noxious models is disrupted (Batesian mimicry [3]), or receivers become more vigilant and learn to avoid perilous mimics (aggressive mimicry [4]). Mimics can moderate this selective constraint by imperfectly resembling multiple models [5], through polymorphisms [6], or by opportunistically deploying mimetic signals [1, 7]. Here we uncover a novel mechanism to escape the constraints of deceptive signaling: phenotypic plasticity allows mimics to deceive targets using multiple guises. Using a combination of behavioral, cell histological, and molecular methods, we show that a coral reef fish, the dusky dottyback (Pseudochromis fuscus), flexibly adapts its body coloration to mimic differently colored reef fishes and in doing so gains multiple fitness benefits. We find that by matching the color of other reef fish, dottybacks increase their success of predation upon juvenile fish prey and are therefore able to deceive their victims by resembling multiple models. Furthermore, we demonstrate that changing color also increases habitat-associated crypsis that decreases the risk of being detected by predators. Hence, when mimics and models share common selective pressures, flexible imitation of models might inherently confer secondary benefits to mimics. Our results show that phenotypic plasticity can act as a mechanism to ease constraints that are typically associated with deception.
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| 10. |
- Franco-Belussi, Lilian, et al.
(författare)
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Internal pigment cells respond to external UV radiation in frogs
- 2016
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 219:9, s. 1378-1383
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Tidskriftsartikel (refereegranskat)abstract
- Fish and amphibians have pigment cells that generate colorful skins important for signaling, camouflage, thermoregulation and protection against ultraviolet radiation (UVR). However, many animals also have pigment cells inside their bodies, on their internal organs and membranes. In contrast to external pigmentation, internal pigmentation is remarkably little studied and its function is not well known. Here, we tested genotoxic effects of UVR and its effects on internal pigmentation in a neotropical frog, Physalaemus nattereri. We found increases in body darkness and internal melanin pigmentation in testes and heart surfaces and in the mesenterium and lumbar region after just a few hours of UVR exposure. The melanin dispersion in melanomacrophages in the liver and melanocytes in testes increased after UV exposure. In addition, the amount of melanin inside melanomacrophages cells also increased. Although mast cells were quickly activated by UVR, only longer UVR exposure resulted in genotoxic effects inside frogs, by increasing the frequency of micronuclei in red blood cells. This is the first study to describe systemic responses of externalUVRon internal melanin pigmentation, melanomacrophages and melanocytes in frogs and thus provides a functional explanation to the presence of internal pigmentation.
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| 11. |
- Gabre, Jonatan L., 1988, et al.
(författare)
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The coelomic epithelium transcriptome from a clonal sea star, Coscinasterias muricata
- 2015
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Ingår i: Marine Genomics. - : Elsevier BV. - 1874-7787. ; 24, s. 245-248
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Tidskriftsartikel (refereegranskat)abstract
- Coscinasterias is a cosmopolitan genus of large asteroid sea stars with the ability of somatic fission as a clonal reproductive strategy. During fission, the animals tear themselves apart across their central disc, where the lost body parts are regenerated afterwards. Here, we have sequenced and subsequently analysed the transcriptome of the coelomic epithelium of a clonal Coscinasterias muricata specimen from New Zealand. Out of the total 389,768 raw reads, 11,344 contigs were assembled and grouped into functions. Raw read and assembled contig sequences are available at NCBI (BioSample: SAMN03371637), while the annotated assembly can be accessed through the project transcriptome browser (compgen.bio.ub.edu/gbrowse/starfish_transcriptome/). Our data is valuable for future detailed exploration of the coelomic epithelium functions as well as for a better understanding of sea star physiology. (c) 2015 Elsevier B.V. All rights reserved.
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| 12. |
- Garcia-Cisneros, A., et al.
(författare)
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Long telomeres are associated with clonality in wild populations of the fissiparous starfish Coscinasterias tenuispina
- 2015
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Ingår i: Heredity. - : Springer Science and Business Media LLC. - 0018-067X .- 1365-2540. ; 115:5, s. 437-443
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Tidskriftsartikel (refereegranskat)abstract
- Telomeres usually shorten during an organism's lifespan and have thus been used as an aging and health marker. When telomeres become sufficiently short, senescence is induced. The most common method of restoring telomere length is via telomerase reverse transcriptase activity, highly expressed during embryogenesis. However, although asexual reproduction from adult tissues has an important role in the life cycles of certain species, its effect on the aging and fitness of wild populations, as well as its implications for the long-term survival of populations with limited genetic variation, is largely unknown. Here we compare relative telomere length of 58 individuals from four populations of the asexually reproducing starfish Coscinasterias tenuispina. Additionally, 12 individuals were used to compare telomere lengths in regenerating and non-regenerating arms, in two different tissues (tube feet and pyloric cecum). The level of clonality was assessed by genotyping the populations based on 12 specific microsatellite loci and relative telomere length was measured via quantitative PCR. The results revealed significantly longer telomeres in Mediterranean populations than Atlantic ones as demonstrated by the Kruskal-Wallis test (K=24.17, significant value: P-value <0.001), with the former also characterized by higher levels of clonality derived from asexual reproduction. Telomeres were furthermore significantly longer in regenerating arms than in non-regenerating arms within individuals (pyloric cecum tissue: Mann-Whitney test, V=299, P-value <10(-6); and tube feet tissue Student's t=2.28, P-value = 0.029). Our study suggests that one of the mechanisms responsible for the long-term somatic maintenance and persistence of clonal populations is telomere elongation.
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| 13. |
- Hansson, Mattias, et al.
(författare)
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Artifactual insulin release from differentiated embryonic stem cells.
- 2004
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Ingår i: Diabetes. - 0012-1797. ; 53:10, s. 2603-9
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Tidskriftsartikel (refereegranskat)abstract
- Several recent reports claim the generation of insulin-producing cells from embryonic stem cells via the differentiation of progenitors that express nestin. Here, we investigate further the properties of these insulin-containing cells. We find that although differentiated cells contain immunoreactive insulin, they do not contain proinsulin-derived C-peptide. Furthermore, we find variable insulin release from these cells upon glucose addition, but C-peptide release is never detected. In addition, many of the insulin-immunoreactive cells are undergoing apoptosis or necrosis. We further show that cells cultured in the presence of a phosphoinositide 3-kinase inhibitor, which previously was reported to facilitate the differentiation of insulin(+) cells, are not C-peptide immunoreactive but take up fluorescein isothiocyanate-labeled insulin from the culture medium. Together, these data suggest that nestin(+) progenitor cells give rise to a population of cells that contain insulin, not as a result of biosynthesis but from the uptake of exogenous insulin. We conclude that C-peptide biosynthesis and secretion should be demonstrated to claim insulin production from embryonic stem cell progeny.
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| 14. |
- Hernroth, Bodil, 1951, et al.
(författare)
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Possibility of Mixed Progenitor Cells in Sea Star Arm Regeneration
- 2010
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Ingår i: Journal of Experimental Zoology Part B-Molecular and Developmental Evolution. - : Wiley. - 1552-5007 .- 1552-5015. ; 314B:6, s. 457-468
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Tidskriftsartikel (refereegranskat)abstract
- In contrast to most vertebrates, invertebrate deuterostome echinoderms, such as the sea star Asterias rubens, undergo regeneration of lost body parts. The current hypothesis suggests that differentiated cells are the main source for regenerating arm in sea stars, but there is little information regarding the origin and identity of these cells. Here, we show that several organs distant to the regenerating arm responded by proliferation, most significantly in the coelomic epithelium and larger cells of the pyloric caeca. Analyzing markers for proliferating cells and parameters indicating cell ageing, such as levels of DNA damage, pigment, and lipofuscin contents as well as telomere length and telomerase activity, we suggest that cells contributing to the new arm likely originate from progenitors rather than differentiated cells. This is the first study showing that cells of mixed origin may be recruited from more distant sources of stem/progenitor cells in a sea star, and the first described indication of a role for pyloric caeca in arm regeneration. Data on growth rate during arm regeneration further indicate that regeneration is at the expense of whole animal growth. We propose a new working hypothesis for arm regeneration in sea stars involving four phases: wound healing by coelomocytes, migration of distant progenitor cells of mixed origin including from pyloric caeca, proliferation in these organs to compensate for cell loss, and finally, local proliferation in the regenerating arm J. Exp. Zool. (Mol. Dev. Evol.) 3148:457-468, 2010. (C) 2010 Wiley-Liss, Inc.
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| 15. |
- Hernroth, Bodil, 1951, et al.
(författare)
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Simulated climate change causes immune suppression and protein damage in the crustacean Nephrops norvegicus
- 2012
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Ingår i: Fish & Shellfish Immunology. - : Elsevier BV. - 1050-4648 .- 1095-9947. ; 33:5, s. 1095-1101
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Tidskriftsartikel (refereegranskat)abstract
- Rising atmospheric carbon dioxide concentration is causing global warming, which affects oceans by elevating water temperature and reducing pH. Crustaceans have been considered tolerant to ocean acidification because of their retained capacity to calcify during subnormal pH. However, we report here that significant immune suppression of the Norway lobster, Nephrops norvegicus, occurs after a 4-month exposure to ocean acidification (OA) at a level predicted for the year 2100 (hypercapnic seawater with a pH lowered by 0.4 units). Experiments carried out at different temperatures (5, 10, 12, 14, 16, and 18 °C) demonstrated that the temperature within this range alone did not affect lobster immune responses. In the OA-treatment, hemocyte numbers were reduced by almost 50% and the phagocytic capacity of the remaining hemocytes was inhibited by 60%. The reduction in hemocyte numbers was not due to increased apoptosis in hematopoetic tissue. Cellular responses to stress were investigated through evaluating advanced glycation end products (AGE) and lipid oxidation in lobster hepatopancreata, and OA-treatment was shown to significantly increase AGEs', indicating stress-induced protein alterations. Furthermore, the extracellular pH of lobster hemolymph was reduced by approximately 0.2 units in the OA-treatment group, indicating either limited pH compensation or buffering capacity. The negative effects of OA-treatment on the nephropidae immune response and tissue homeostasis were more pronounced at higher temperatures (12–18 °C versus 5 °C), which may potentially affect disease severity and spread. Our results signify that ocean acidification may have adverse effects on the physiology of lobsters, which previously had been overlooked in studies of basic parameters such as lobster growth or calcification.
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| 16. |
- Holm, K., et al.
(författare)
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Induced cell proliferation in putative haematopoietic tissues of the sea star, Asterias rubens (L.)
- 2008
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 211:16, s. 2551-2558
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Tidskriftsartikel (refereegranskat)abstract
- The coelomic fluid of the echinoderm Asterias rubens possesses large populations of circulating coelomocytes. This study aimed to expand the knowledge about the haematopoietic sources of these cells. Injection of the immune-stimulating molecules lipopolysaccharide (LPS) and concanavalin A (ConA) resulted in an increase in coelomocytes. To investigate if these molecules induce cell proliferation in putative haematopoietic tissues (HPTs), short-term exposure of the substitute nucleotide 5-bromo-2'-deoxyuridine (BrdU) was conducted. Immunohistochemical analysis, using fluorescein-labelled antibodies to trace BrdU, showed pronounced cell division in the coelomic epithelium and axial organ. In the pyloric caeca, not considered as an HPT, proliferation was not detected. BrdU labelling of monolayers of cells obtained by collagenase treatment of coelomic epithelium, axial organ and Tiedemann body revealed induced cell proliferation in response to both LPS and ConA while proliferation of pyloric caeca and circulating coelomocytes remained sparse. By using confocal microscopy it was observed that both the morphology and functional behaviour of cells released from explants of coelomic epithelium showed high similarity to those of circulating phagocytes. It was concluded that the increased coelomocyte numbers observed in response to LPS and ConA were reflected in an induced cell proliferation in coelomic epithelium, axial organ and Tiedemann body, which reinforces the idea that these organs are HPTs and the sources of coelomocyte renewal.
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| 17. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Assembly pathway of the anastral Drosophila oocyte meiosis I spindle
- 2005
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Ingår i: Journal of Cell Science. - 0021-9533. ; 118:8, s. 1745-1755
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Tidskriftsartikel (refereegranskat)abstract
- Oocyte meiotic spindles of many species are anastral and lack centrosomes to nucleate microtubules. Assembly of anastral spindles occurs by a pathway that differs from that of most mitotic spindles. Here we analyze assembly of the Drosophila oocyte meiosis I spindle and the role of the Nonclaret disjunctional (Ncd) motor in spindle assembly using mild-type and mutant Ncd fused to GFP. Unexpectedly, we observe motor-associated asters at germinal vesicle breakdown that migrate towards the condensed chromosomes, where they nucleate microtubules at the chromosomes. Newly nucleated microtubules are randomly oriented, then become organized around the bivalent chromosomes. We show that the meiotic spindle forms by lateral associations of microtubule-coated chromosomes into a bipolar spindle. Lateral interactions between microtubule-associated bivalent chromosomes may be mediated by microtubule crosslinking by the Ncd motor, based on analysis of fixed oocytes. We report here that spindle assembly occurs in an ncd mutant defective for microtubule motility, but lateral interactions between microtubule-coated chromosomes are unstable, indicating that Ncd movement along microtubules is needed to stabilize interactions between chromosomes. A more severe ncd mutant that probably lacks ATPase activity prevents formation of lateral interactions between chromosomes and causes defective microtubule elongation. Anastral Drosophila oocyte meiosis I spindle assembly thus involves motor-associated asters to nucleate microtubules and Ncd motor activity to form and stabilize interactions between microtubule-associated chromosomes during the assembly process. This is the first complete account of assembly of an anastral spindle and the specific steps that require Ncd motor activity, revealing new and unexpected features of the process.
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| 18. |
- Nilsson Sköld, Helen, 1970
(författare)
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Fina fisken - forskaren och fisken snackar färg
- 2009
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Ingår i: havsutsikt. ; 2, s. 10-11
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Alla djur har olika färger och mönster. Det beror på den unika fördelningen och sammansättningen av olika färgpigment på kroppen. Pigmenten bildas i speciella celler för att sedan transporteras ut i hår och päls hos människa och andra däggdjur. I fisk och grodor används pigmenten istället för att växla färg.
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| 19. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Fish Chromatophores - From Molecular Motors to Animal Behavior
- 2016
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Ingår i: International Review of Cell and Molecular Biology. - : Elsevier. - 1937-6448. ; 321, s. 171-219
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Forskningsöversikt (refereegranskat)abstract
- Chromatophores are pigment-bearing cells of lower vertebrates, including fish that cater for the ability of individual animals to shift body coloration and pattern. Color change provides dynamic camouflage and various kinds of communication. It is also a spectacular example of phenotypic plasticity, and of significant importance for adaptation and survival in novel environments. Through different cellular mechanisms, color change can occur within minutes or more slowly over weeks. Chromatophores have different pigment types and are located not only in the skin, but also in the eyes and internally. While morphological color change, including seasonal color change, has received a lot of interest from evolutionary biologists and behavioral ecologists, the more rapid physiological color change has been largely a research subject for cell physiologists. In this cross-disciplinary review, we have highlighted emerging trends in pigment cell research and identified unsolved problems for future research.
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| 20. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Hormonal regulation of colour change in eyes of a cryptic fish
- 2015
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Ingår i: Biology Open. - : The Company of Biologists. - 2046-6390. ; 4:2, s. 206-211
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Tidskriftsartikel (refereegranskat)abstract
- Colour change of the skin in lower vertebrates such as fish has been a subject of great scientific and public interest. However, colour change also takes place in eyes of fish and while an increasing amount of data indicates its importance in behaviour, very little is known about its regulation. Here, we report that both eye and skin coloration change in response to white to black background adaptation in live sand goby Pomatoschistus minutes, a bentic marine fish. Through in vitro experiments, we show that noradrenaline and melanocyte concentrating hormone (MCH) treatments cause aggregation of pigment organelles in the eye chromatophores. Daylight had no aggregating effect. Combining forskolin to elevate intracellular cyclic adenosine monophosphate (cAMP) with MCH resulted in complete pigment dispersal and darkening of the eyes, whereas combining prolactin, adrenocorticotrophic hormone (ACTH) or melanocyte stimulating hormone (alpha-MSH) with MCH resulted in more yellow and red eyes. ACTH and MSH also induced dispersal in the melanophores, resulting in overall darker eyes. By comparing analysis of eyes, skin and peritoneum, we conclude that the regulation pattern is similar between these different tissues in this species which is relevant for the cryptic life strategy of this species. With the exception of ACTH which resulted in most prominent melanophore pigment dispersal in the eyes, all other treatments provided similar results between tissue types. To our knowledge, this is the first study that has directly analysed hormonal regulation of physiological colour change in eyes of fish.
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| 21. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Motoric impairment following manganese exposure in asteroide chinoderms
- 2015
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Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 167, s. 31-37
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Tidskriftsartikel (refereegranskat)abstract
- In the oceans, naturally occurring manganese (Mn) is released from the sediments during events of hypoxia. While neuro- and immuno-toxic effects of bioavailable manganese are well documented for crustaceans, studies of similar effects of manganese on other marine invertebrates are comparatively few. Here, we developed a new functional test “the repeated turning assay” to investigate if manganese exposure at ∼12 mg L−1 affected motoric behaviour of two asteroid echinoderms, the Common sea star, Asterias rubens, and the Black brittle star, Ophiocomina nigra. By measuring of the turning-over capacity, from dorsal to ventral position, after one and two weeks of manganese exposure, we showed that for both species Mn exposure significantly delayed the ability to turn. After a recovery period of two weeks, the capacity of turning-over was not restored to that of unexposed animals neither for A. rubens nor for O. nigra. Further investigation of sea stars showed that Mn accumulated ∼5 fold in the tube feet, organs involved in their turning-over activity, and the high concentration remained after the recovery period. In the tube feet we also recorded an increased activity of acetylcholinesterase (AChE), here used as a proxy for neuromuscular disturbances. The results indicated that Mn induces neuromuscular disturbance in echinoderms which is important news, given that previous studies have concluded that adult echinoderms are relatively tolerant to Mn.
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| 22. |
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| 23. |
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| 24. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Rapid color change in fish and amphibians - function, regulation, and emerging applications.
- 2013
-
Ingår i: Pigment Cell & Melanoma Research. - : Wiley. - 1755-1471 .- 1755-148X. ; 26:1, s. 29-38
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Forskningsöversikt (refereegranskat)abstract
- Physiological color change is important for background matching, thermoregulation as well as signaling and is in vertebrates mediated by synchronous intracellular transport of pigmented organelles in chromatophores. We describe functions of and animal situations where color change occurs. A summary of endogenous and external factors that regulate this color change in fish and amphibians is provided, with special emphasis on extracellular stimuli. We describe not only color change in skin, but also highlight studies on color change that occurs using chromatophores in other areas such as iris and on the inside of the body. In addition, we discuss the growing field that applies melanophores and skin color in toxicology and as biosensors, and point out research areas with future potential.
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| 25. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Regulatory control of both microtubule- and actin-dependent fish melanosome movement
- 2002
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Ingår i: Pigment Cell Research. - 0893-5785. ; 15:5, s. 357-366
-
Tidskriftsartikel (refereegranskat)abstract
- In fish melanophores, melanosomes can either aggregate around the cell centre or disperse uniformly throughout the cell. This organelle transport involves microtubule- and actin-dependent motors and is regulated by extracellular stimuli that modulate levels of intracellular cyclic adenosine 3-phosphate (cAMP). We analysed melanosome dynamics in Atlantic cod melanophores under different experimental conditions in order to increase the understanding of the regulation and relative contribution of the transport systems involved. By inhibiting dynein function via injection of inhibitory antidynein IgGs, and modulating cAMP levels using forskolin, we present cellular evidence that dynein is inactivated by increased cAMP during dispersion and that the kinesin-related motor is inactivated by low cAMP levels during aggregation. Inhibition of dynein further resulted in hyperdispersed melanosomes, which subsequently reversed movement towards a more normal dispersed state, pointing towards a peripheral feedback regulation in maintaining the evenly dispersed state. This reversal was blocked by noradrenaline. Analysis of actin-mediated melanosome movements shows that actin suppresses aggregation and dispersion, and indicates the possibility of down-regulating actin-dependent melanosome movement by noradrenaline. Data from immuno-electron microscopy indicate that myosinV is associated with fish melanosomes. Taken together, our study presents evidence that points towards a model where both microtubule- and actin-mediated melanosome transport are synchronously regulated during aggregation and dispersion, and this provides a cell physiological explanation behind the exceptionally fast rate of background adaptation in fish.
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| 26. |
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| 27. |
- Nilsson Sköld, Helen, 1970
(författare)
-
Sexuell eller klonal förökning, det är frågan!
- 2013
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Ingår i: Havsutsikt. - 1104-0513. ; 1, s. 18-19
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Att föröka sig sexuellt är krångligt och bryter lyckosamma genkombinationer. Trots det är det den absolut vanligaste formen av reproduktion i både djur- och växtriket. Att klona sig verkar dock vara bra på kort sikt och för enskilda individer. Varför sexuell reproduktion dominerar är en av de gamla klassiska frågorna inom biologin. Jag har här gett mig ut i naturen för att fråga några marina arter varför de gör som de gör !
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| 28. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
-
Skin Biopsies as Tools to Measure Fish Coloration and Colour Change
- 2011
-
Ingår i: InTech. ; , s. 1-18
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- A biopsy is a link between the whole organism and its cells. Many recent advances in the field of fish coloration have been gained through experimentation on skin biopsies. In particular, this strategy has allowed the in-depth knowledge from pigment cell physiology to be applied to wider topics, such as behavioral ecology. Moreover, melanophores from fish and frogs have long served as models for a general understanding of intracellular transport and organelle positioning. For this purpose, fish skin biopsies have frequently been used for isolation of pigment cells but also for isolation of fibroblasts. In fish pigmentation research, skin biopsies have also been used to understand what causes changes in the skin's overall appearance, especially in the context of short or long-term modulation of tissue coloration. Examples of this are how many fishes rapidly change their colour during courtship or aggressive displays. Here, we review our methodology for the use of skin biopsies in research on fish coloration – from pigment cell physiology to animal behavior. We also highlight some of the most significant findings from this research, and present unsolved issues and suggestions for future directions. In this chapter, we will provide a description of the experimental procedures we have used to manipulate and analyze fish skin biopsies in the context of fish coloration - from chromatophores to animal behavior. Since our research has mainly focused on marine fishes, the protocols (e.g. the choice of buffers) were chosen to suit such animals. However, with minor modifications, these methods will likely work also on most fresh water species. Many of the experimental procedures are fast to assess and easy to perform, and we therefore encourage the experimentation on fish biopsies for use in education. The protocols described in this chapter are also suitable for such exercises.
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| 29. |
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| 30. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
-
The cytoskeleton in fish melanophore melanosome positioning.
- 2002
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Ingår i: Microscopy research and technique. - : Wiley. - 1059-910X. ; 58:6, s. 464-9
-
Tidskriftsartikel (refereegranskat)abstract
- Melanophore melanosomes organelles can be regulated to move and locate correspondingly to many other different organelle types. Comparing lessons from analysis of a specific melanosome distribution can, therefore, contribute to the understanding of distribution of other organelles, and vice versa. From such data, it is now generally accepted that microtubules provide directed long-distance movement, while cell peripheral movements include microfilaments. In fish melanophores, both actin and dynein exhibit counter-forces to the kinesin-like protein in maintaining the evenly dispersed state, while actin and kinesin exhibit counter-forces to dynein in many other systems. Lessons from elevating cAMP levels indicate the presence of a peripheral feedback regulatory system involved in maintaining the evenly dispersed state. Studies from dynein inhibition suggest that the kinesin-like protein involved in fish melanosome dispersal is regulated in contrast to many other systems. One would further expect melanosome transport to be regulated also on actin/myosin, in order to prevent actin-dependent capture of melanosomes during the microtubule-dependent aggregation and dispersion. General findings will be discussed in comparison with positioning and movement of other organelle types in cells. Finally, recent data on melanosome-dependent organising of microtubules show that dynein is involved in nucleating microtubules extending from melanosome aggregates in melanophore fragments.
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| 31. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
-
The pattern of cell proliferation during budding in the colonial ascidian Diplosoma listerianum
- 2011
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Ingår i: Biological Bulletin.
-
Tidskriftsartikel (refereegranskat)abstract
- Many invertebrates reproduce asexually by budding, but morphogenesis and the role of cell proliferation in this diverse and non-conserved regeneration-like process are generally poorly understood and particularly little investigated in didemnid ascidians. We here analysed cell proliferation patterns and telomerase activity during budding in the colonial didemnid ascidian Diplosoma listerianum, with special focus on the thoracic bud where a new brain develops de novo. To help define developmental stages of the thoracic bud, the distribution of acetylated tubulin was also examined. We found extensive cell proliferation in both the thoracic and abdominal buds of D. listerianum as well as higher telomerase activity in bud tissue compared to adult tissues. In the parent adult, proliferation was found in various tissues, but was especially intense in the adult esophagus and epicardial structures that protrude into the proliferating and developing buds, confirming these tissues as the primary source of the cells that form the buds. The neural complex in the thoracic bud forms from a hollow tube that appears to separate into the neural gland and the cerebral ganglion. While most of the bud undergoes proliferation, including the hollow tube and the neural gland, the cerebral ganglion shows little or no proliferation. Pulse-chase labelling experiments indicate that the ganglion, as well as the myocardium, in adult zooids are instead composed of postmitotic cells.
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| 32. |
- Olsson, Karin H., 1979, et al.
(författare)
-
Dark eyes in female sand gobies indicate readiness to spawn
- 2017
-
Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 12:6
-
Tidskriftsartikel (refereegranskat)abstract
- In animals, colorful and conspicuous ornaments enhance individual attractiveness to potential mates, but are typically tempered by natural selection for crypsis and predator protection. In species where males compete for females, this can lead to highly ornamented males competing for mating opportunities with choosy females, and vice versa. However, even where males compete for mating opportunities, females may exhibit conspicuous displays. These female displays are often poorly understood and it may be unclear whether they declare mating intent, signal intrasexual aggression or form a target for male mate preference. We examined the function of the conspicuous dark eyes that female sand gobies temporarily display during courtship by experimentally testing if males preferred to associate with females with artificially darkened eyes and if dark eyes are displayed during female aggression. By observing interactions between a male and two females freely associating in an aquarium we also investigated in which context females naturally displayed dark eyes. We found that dark eyes were more likely to be displayed by more gravid females than less gravid females and possibly ahead of spawning, but that males did not respond behaviorally to dark eyes or prefer dark-eyed females. Females behaving aggressively did not display dark eyes. We suggest that dark eyes are not a signal per se but may be an aspect of female mate choice, possibly related to vision.
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| 33. |
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| 34. |
- Rodriguez-Grana, Laura, 1969, et al.
(författare)
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Gender specific ageing and non-mendelian inheritance of oxidative damage in marine copepods
- 2010
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Ingår i: Marine Ecology Progress Series. - 0171-8630. ; 401, s. 1-13
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Tidskriftsartikel (refereegranskat)abstract
- Ageing in the marine pelagic copepod Acartia tonsa results in decreased feeding and production rates associated with an increase in the accumulation of protein oxidative damage, as predicted by the oxidative stress hypothesis. In laboratory experiments, we estimated sex-specific ageing effects on feeding and oxidative damage and on egg production rates of adult females. We also determined maternal effects on offspring by measuring egg hatching success and oxidative damage of nauplii from mothers of different ages. Males manifested more oxidative damage with age than females, providing an alternative explanation for the shorter life span in males. Older females produced fewer offspring, and nauplii with higher protein oxidative damage, than younger females. This study forms an empirical basis to link ageing, life span, sex differences and maternal fitness in animals that also reflects natural copepod population dynamics. Individual ageing processes and the resulting age structure in the population modulate mortality risk, parental effects on offspring performance, reproductive investment, and pelagic energy fluxes.
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| 35. |
- Rosenberg, Rutger, 1943, et al.
(författare)
-
Biology of the basket star Gorgonocephalus caputmedusae (L.)
- 2005
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Ingår i: Marine Biology. - : Springer Science and Business Media LLC. - 0025-3162 .- 1432-1793. ; 148, s. 43-50
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Tidskriftsartikel (refereegranskat)abstract
- Ophiurid basket stars belonging to the family Gorgonocephalidae are distributed from the Arctic to the Antarctic and from the shallow subtidal to the deep sea, but their biology remains poorly known. In situ observations at the mouth of the Oslofjord by a remotely operated vehicle showed that Gorgonocephalus caputmedusae had a patchy distribution at 85 to 120 m water depth and frequently occurred in association with the gorgonian Paramuricea placomus and the coral Lophelia pertusa. Morphological and histological studies show that G. caputmedusae is well adapted to capture macroplanktonic prey. Histological examination of the arms revealed the presence of a thick layer of dermal mutable connective tissue which is probably an energyefficient way to maintain its feeding posture against the current. This layer is connected to the nerve cord suggesting that the passive mechanical properties (stiffness) is controlled by the nervous system. In the distal parts of the arms, each segment has a pair of sticky tube feet and a sophisticated system of spines and hooks, which are connected to muscles and collagenous tendons. In combination, these features were shown, in an experimental flume study, to be used for capturing the locally abundant krill species Meganyctiphanes norvegica. This is the first documentation of G. caputmedusae of this kind
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| 36. |
- Sciambi, C. J., et al.
(författare)
-
A bidirectional kinesin motor in live Drosophila embryos
- 2005
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Ingår i: Traffic. - 1398-9219. ; 6:11, s. 1036-1046
-
Tidskriftsartikel (refereegranskat)abstract
- Spindle assembly and elongation involve poleward and away-from-the-pole forces produced by microtubule dynamics and spindle-associated motors. Here, we show that a bidirectional Drosophila Kinesin-14 motor that moves either to the microtubule plus or minus end in vitro unexpectedly causes only minor spindle defects in vivo. However, spindles of mutant embryos are longer than wild type, consistent with increased plus-end motor activity. Strikingly, suppressing spindle dynamics by depriving embryos of oxygen causes the bidirectional motor to show increased accumulation at distal or plus ends of astral microtubules relative to wild type, an effect not observed for a mutant motor defective in motility. Increased motor accumulation at microtubule plus ends may be due to increased slow plus-end movement of the bidirectional motor under hypoxia, caused by perturbation of microtubule dynamics or inactivation of the only other known Drosophila minus-end spindle motor, cytoplasmic dynein. Negative-stain electron microscopy images are consistent with highly cooperative motor binding to microtubules, and gliding assays show dependence on motor density for motility. Mutant effects of the bidirectional motor on spindle function may be suppressed under normal conditions by motor: motor interactions and minus-end movement induced by spindle dynamics. These forces may also bias wild-type motor movement toward microtubule minus ends in live cells. Our findings link motor : motor interactions to function in vivo by showing that motor density, together with cellular dynamics, may influence motor function in live cells.
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| 37. |
- Styf, Hannah K, 1983, et al.
(författare)
-
Embryonic response to long-term exposure of the marine crustacean Nephrops norvegicus to ocean acidification and elevated temperature
- 2013
-
Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 3:15, s. 5055-5065
-
Tidskriftsartikel (refereegranskat)abstract
- Due to anthropogenic CO2 emissions, our oceans have gradually become warmer and more acidic. To better understand the consequences of this, there is a need for long-term (months) and multistressor experiments. Earlier research demonstrates that the effects of global climate change are specific to species and life stages. We exposed berried Norway lobsters (Nephrops norvegicus), during 4 months to the combination of six ecologically relevant temperatures (5–18°C) and reduced pH (by 0.4 units). Embryonic responses were investigated by quantifying proxies for development rate and fitness including: % yolk consumption, mean heart rate, rate of oxygen consumption, and oxidative stress. We found no interactions between temperature and pH, and reduced pH only affected the level of oxidative stress significantly, with a higher level of oxidative stress in the controls. Increased temperature and % yolk consumed had positive effects on all parameters except on oxidative stress, which did not change in response to temperature. There was a difference in development rate between the ranges of 5–10°C (Q10: 5.4) and 10–18°C (Q10: 2.9), implicating a thermal break point at 10°C or below. No thermal limit to a further increased development rate was found. The insensitivity of N. norvegicus embryos to low pH might be explained by adaptation to a pH-reduced external habitat and/or internal hypercapnia during incubation. Our results thus indicate that this species would benefit from global warming and be able to withstand the predicted decrease in ocean pH in the next century during their earliest life stages. However, future studies need to combine low pH and elevated temperature treatments with hypoxia as hypoxic events are frequently and increasingly occurring in the habitat of benthic species.
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| 38. |
- Sundin, Josefin, 1981-, et al.
(författare)
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No effect of elevated carbon dioxide on reproductive behaviors in the three-spined stickleback
- 2017
-
Ingår i: Behavioral Ecology. - : Oxford University Press (OUP). - 1045-2249 .- 1465-7279. ; 28:6, s. 1482-1491
-
Tidskriftsartikel (refereegranskat)abstract
- Ocean acidification, the reduction in ocean pH resulting from anthropogenic emissions of carbon dioxide (CO2), has been predicted to alter the behavior of fishes. During experimental exposure to CO2 concentrations projected for the year 2100 (similar to 1000 mu atm), fish have been reported to display disturbances in activity, learning, behavioral lateralization, and even attraction to predator cues. Reproductive behaviors have received far less attention, despite an intensive research effort on ocean acidification and its ecological importance. Here, we investigate whether elevated levels of CO2 affect reproduction in breeding pairs of the three-spined stickleback, Gasterosteus aculeatus, a model species in behavioral, evolutionary ecology, and environmental toxicology. We found that males under both present day levels (400 mu atm) and future levels (1000 mu atm) of CO2 developed normal sexual ornaments, pursued normal nest building activities, exhibited similar levels of courtship behaviors and displacement fanning, and had the same mating probability. Moreover, fanning behavior during the paternal care period followed what is expected for the species for males from both treatments, and there was no effect of treatment on the numbers of offspring produced. This study is the first to investigate the effect of elevated CO2 on the complete breeding cycle in detail, studying an array of highly fitness-relevant traits. Our study showing surprising resilience of fish reproduction is an important contribution in order to realistically predict the impacts of future ocean acidification.
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| 39. |
- Svanfeldt, Karin, et al.
(författare)
-
Repair of UV-induced DNA damage in shallow water colonial marine species
- 2014
-
Ingår i: Journal of Experimental Marine Biology and Ecology. - : Elsevier BV. - 0022-0981. ; 452, s. 40-46
-
Tidskriftsartikel (refereegranskat)abstract
- Ultraviolet radiation (UVR) may cause significant DNA damages when interacting with shallow water organisms, primarily in the tropics. Here we investigate DNA repair kinetics in two shallow water colonial marine invertebrates, the scleractinian coral Seriatopora hystrix and the colonial tunicate Botryllus schlosseri. Cells from both species were irradiated with UVA/UVB in vitro. Using the alkaline (B. schlosseri) and the neutral (S. hystrix) versions of the comet assay, DNA damage and repair were measured. After 24. h, little DNA repair was recorded in the irradiated Botryllus cells for both types of radiation (UVB 3.55. W/s/UVA 8.09. W/s, 15. min radiation each), revealing twice (30%) as much apoptotic cells as controls. Cells of S. hystrix showed a highly efficient DNA repair capacity (i.e. complete DNA repair within 30. min post-irradiation), coincident with their endurance to reactive oxygen species impacts. Therefore, while S. hystrix and likely other shallow water corals use efficient DNA repair mechanisms, B. schlosseri and possibly other similar species are reliant on UVR sheltered sites to maintain DNA integrity. The low repair capacity of B. schlosseri might be explained by the 'disposable soma' concept, where zooidal soma in this species is cast off and recycled on a weekly basis. Further research is needed to elucidate the spectrum of responses used by shallow water sedentary marine invertebrates to cope with daily high UVR levels. © 2013 Elsevier B.V.
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| 40. |
- Svensson, P. A., et al.
(författare)
-
Chromatic interaction between egg pigmentation and skin chromatophores in the nuptial coloration of female two-spotted gobies
- 2005
-
Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 208:23, s. 4391-4397
-
Tidskriftsartikel (refereegranskat)abstract
- In two-spotted gobies (Gobiusculus flavescens Fabricius 1779), females develop an orange belly as they approach sexual maturity. Bright belly coloration is preferred by males and has been suggested to act as a female ornament. This coloration is unusual in that it originates partly from pigmentation of the abdominal skin but also from strongly pigmented gonads directly visible through the skin. In addition, females have been observed to temporarily become more colourful during courtship and competition. To understand how gonad and skin pigmentation interact in this nuptial coloration, the potential for colour modification via regulation of skin chromatophores was investigated. Noradrenaline caused aggregation of chromatophore pigment and was used to experimentally reduce the contribution of skin chromatophores to the nuptial coloration. Chromatophore pigment aggregation caused bellies to become less colourful and abdominal skin biopsies to become less colourful and more transparent. There was a strong positive relationship between belly coloration and the coloration of the underlying gonads. This shows that belly coloration honestly reflects egg pigmentation, mainly because the transparency of the abdominal skin allows other fish to see the gonads directly. Interestingly, when noradrenaline caused pigment to aggregate and thereby increased the transparency of the skin, the relationship between belly and gonad coloration weakened. We conclude that female G. flavescens have a potential to use skin chromatophores to rapidly alter their nuptial coloration, thereby affecting the efficacy with which information about gonad coloration is conveyed.
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| 41. |
- Wood, Hannah L., 1980, et al.
(författare)
-
Health and population dependent effects of ocean acidification on the marine isopod Idotea balthica
- 2014
-
Ingår i: Marine Biology. - : Springer Science and Business Media LLC. - 0025-3162 .- 1432-1793. ; 161:10, s. 2423-2431
-
Tidskriftsartikel (refereegranskat)abstract
- Three populations of the grazing isopod Idotea balthica were exposed to high CO2 treatment for a period of 20 days to investigate the effect of ocean acidification (OA) on animal health and immunocompetence. The results of the populations from more saline habitats were comparable and showed a 60–80 % decrease in immune response as a result of the high CO2 treatment. Analysis of protein carbonyls showed no treatment effect, indicating that short-term OA does not increase oxidative protein damage. Meanwhile, the third tested population from the lower saline Baltic Sea had higher background protein carbonyl levels. Ocean acidification in addition to this resulted in 100 % mortality. The results of this study show that OA reduced immunocompetence of this marine isopod. In addition, populations and individuals in poor health are potentially at greater risk to succumb under OA.
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| 42. |
- Wood, Hannah L., 1980, et al.
(författare)
-
Population-dependent effects of ocean acidification
- 2016
-
Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 283:1828
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Tidskriftsartikel (refereegranskat)abstract
- Elevated carbon dioxide levels and the resultant ocean acidification (OA) are changing the abiotic conditions of the oceans at a greater rate than ever before and placing pressure on marine species. Understanding the response of marine fauna to this change is critical for understanding the effects of OA. Population-level variation in OA tolerance is highly relevant and important in the determination of ecosystem resilience and persistence, but has received little focus to date. In this study, whether OA has the same biological consequences in high-salinity-acclimated population versus a low-salinity-acclimated population of the same species was investigated in the marine isopod Idotea balthica. The populations were found to have physiologically different responses to OA. While survival rate was similar between the two study populations at a future CO2 level of 1000 ppm, and both populations showed increased oxidative stress, the metabolic rate and osmoregulatory activity differed significantly between the two populations. The results of this study demonstrate that the physiological response to OA of populations from different salinities can vary. Population-level variation and the environment provenance of individuals used in OA experiments should be taken into account for the evaluation and prediction of climate change effects.
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