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Abstract
Thermoregulation is critical for survival and animals therefore employ strategies to keep their body temperature within a physiological range. As ectotherms, fish exclusively rely on behavioral strategies for thermoregulation. Different species of fish seek out their specific optimal temperatures through thermal navigation by biasing behavioral output based on experienced environmental temperatures. Like other vertebrates, fish sense water temperature using thermoreceptors in trigeminal and dorsal root ganglia neurons that innervate the skin. Recent research in larval zebrafish has revealed how neural circuits subsequently transform this sensation of temperature into thermoregulatory behaviors. Across fish species, thermoregulatory strategies rely on a modulation of swim vigor based on current temperature and a modulation of turning based on temperature change. Interestingly, temperature preferences are not fixed but depend on other environmental cues and internal states. The following review is intended as an overview on the current knowledge as well as open questions in fish thermoregulation.
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Affiliation(s)
- Martin Haesemeyer
- The Ohio State University College of Medicine, Department of Neuroscience, Columbus, OH, USA.
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Borissov RS, Espeland S, Iversen MH. Evaluation of the i-STAT (portable clinical analyser) for measuring haematological parameters in Atlantic cod (Gadus morhua) at different CO 2 and temperature conditions. FISH PHYSIOLOGY AND BIOCHEMISTRY 2019; 45:1551-1562. [PMID: 31583489 DOI: 10.1007/s10695-019-00638-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 03/28/2019] [Indexed: 06/10/2023]
Abstract
Portable clinical analysers are gradually being involved in on-site assessment of haematic parameters in fish. The purpose of this study was to evaluate the i-STAT portable clinical analyser (i-STAT PCA) for accuracy and reliability of measuring blood pH, partial pressure of oxygen (pO2), haematocrit, haemoglobin, sodium, potassium and calcium in Atlantic cod (Gadus morhua). Haematological parameters detected with the i-STAT PCA were compared with conventional laboratory techniques (CLTs). Two types of disposable cartridges were used (CHEM8+ and CG4+) with the i-STAT PCA, and experiments were performed at two different temperature regimes (5 °C and 15 °C) and four different carbon dioxide (CO2) levels (0%, 0.1%, 0.5% and 1%). All blood parameters measured with the i-STAT PCA showed heterogeneous inaccuracy under the tested conditions, but the highest discrepancies were registered in blood pO2. The i-STAT PCA systematically overestimated the pO2 measurements. Our research suggests that i-STAT PCA is not an appropriate tool for pO2 measurements especially in coldwater fish species. The i-STAT PCA consistently underestimated the pH and haematocrit values especially at a lower temperature, although those parameters indicate significant high correlation at 15 °C. Furthermore, the analysed ions showed overestimation of sodium and underestimation of potassium and calcium.
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Affiliation(s)
| | - Sølvi Espeland
- Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Martin H Iversen
- Faculty of Biosciences and Aquaculture, Nord University, 8049, Bodø, Norway
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Nelson C, Barlow SL, Berenbrink M. ATP-induced reversed thermal sensitivity of O 2 binding in both major haemoglobin polymorphs of the non-endothermic Atlantic cod, Gadus morhua. ACTA ACUST UNITED AC 2019; 222:jeb.200279. [PMID: 31160424 DOI: 10.1242/jeb.200279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/23/2019] [Indexed: 11/20/2022]
Abstract
Atlantic cod is a species that is affected by climate change, with some populations being exposed to higher temperatures than others. The two polymorphs of its major haemoglobin type (HbI) show an inverse change in frequency along a latitudinal temperature cline in the North East Atlantic, which has been associated with differences in population performance and behavioural traits. An earlier study at the northern distribution limit of the species reported differential temperature sensitivities of red blood cell oxygen (O2) affinity between the northern cold-water HbI-2 polymorph and its southern, warm-water HbI-1 counter-part, which has since widely been held as adaptive for the species across its distributional range. The present study critically re-examined this hypothesis by comparing the thermal sensitivity of O2 binding in both purified HbI polymorphs from the southern, high-temperature distribution limit of the species under controlled conditions of allosteric modifiers of Hb function. Contrary to the prevailing view, the O2 affinity of the major HbI polymorphs did not differ from each other under any of the tested conditions. Depending on pH and ATP concentration, the temperature-sensitive and temperature-insensitive Hb-O2 affinity phenotypes - previously exclusively ascribed to HbI-1 and HbI-2, respectively - could be induced in both HbI polymorphs. These results are the first to establish a molecular mechanism behind a reversed temperature dependence of red blood cell O2 affinity in a non-endotherm fish and lay the basis for future studies on alternative mechanisms behind the differences in distribution, performance and behavioural traits associated with the different HbI polymorphs of Atlantic cod.
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Affiliation(s)
- Charlotte Nelson
- Institute of Integrative Biology, The University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK .,Department of Zoology, The University of British Columbia, Biological Sciences Building, 6270 University Boulevard, Vancouver, BC, V6T 1Z4, Canada
| | - Samantha L Barlow
- Institute of Integrative Biology, The University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK
| | - Michael Berenbrink
- Institute of Integrative Biology, The University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK
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Barlow SL, Metcalfe J, Righton DA, Berenbrink M. Life on the edge: O2 binding in Atlantic cod red blood cells near their southern distribution limit is not sensitive to temperature or haemoglobin genotype. ACTA ACUST UNITED AC 2017; 220:414-424. [PMID: 28148818 PMCID: PMC5312735 DOI: 10.1242/jeb.141044] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 11/14/2016] [Indexed: 01/19/2023]
Abstract
Atlantic cod are a commercially important species believed to be threatened by warming seas near their southern, equatorward upper thermal edge of distribution. Limitations to circulatory O2 transport, in particular cardiac output, and the geographic distribution of functionally different haemoglobin (Hb) genotypes have separately been suggested to play a role in setting thermal tolerance in this species. The present study assessed the thermal sensitivity of O2 binding in Atlantic cod red blood cells with different Hb genotypes near their upper thermal distribution limit and modelled its consequences for the arterio-venous O2 saturation difference, Sa–vO2, another major determinant of circulatory O2 supply rate. The results showed statistically indistinguishable red blood cell O2 binding between the three HbI genotypes in wild-caught Atlantic cod from the Irish Sea (53° N). Red blood cells had an unusually low O2 affinity, with reduced or even reversed thermal sensitivity between pH 7.4 and 7.9, and 5.0 and 20.0°C. This was paired with strongly pH-dependent affinity and cooperativity of red blood cell O2 binding (Bohr and Root effects). Modelling of Sa–vO2 at physiological pH, temperature and O2 partial pressures revealed a substantial capacity for increases in Sa–vO2 to meet rising tissue O2 demands at 5.0 and 12.5°C, but not at 20°C. Furthermore, there was no evidence for an increase of maximal Sa–vO2 with temperature. It is suggested that Atlantic cod at such high temperatures may solely depend on increases in cardiac output and blood O2 capacity, or thermal acclimatisation of metabolic rate, for matching circulatory O2 supply to tissue demand. Highlighted Article: Red blood cell oxygen binding affinity in Atlantic cod near their southern, warmer limit of distribution is largely temperature independent and not affected by functional differences between their major haemoglobin genotypes.
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Affiliation(s)
- Samantha L Barlow
- Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, The University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK
| | - Julian Metcalfe
- Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Lowestoft NR33 0HT, UK
| | - David A Righton
- Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Lowestoft NR33 0HT, UK
| | - Michael Berenbrink
- Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, The University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK
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Andersen Ø, De Rosa MC, Yadav P, Pirolli D, Fernandes JMO, Berg PR, Jentoft S, Andrè C. The conserved Phe GH5 of importance for hemoglobin intersubunit contact is mutated in gadoid fish. BMC Evol Biol 2014; 14:54. [PMID: 24655798 PMCID: PMC3998052 DOI: 10.1186/1471-2148-14-54] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 03/06/2014] [Indexed: 02/04/2023] Open
Abstract
Background Functionality of the tetrameric hemoglobin molecule seems to be determined by a few amino acids located in key positions. Oxygen binding encompasses structural changes at the interfaces between the α1β2 and α2β1 dimers, but also subunit interactions are important for the oxygen binding affinity and stability. The latter packing contacts include the conserved Arg B12 interacting with Phe GH5, which is replaced by Leu and Tyr in the αA and αD chains, respectively, of birds and reptiles. Results Searching all known hemoglobins from a variety of gnathostome species (jawed vertebrates) revealed the almost invariant Arg B12 coded by the AGG triplet positioned at an exon-intron boundary. Rare substitutions of Arg B12 in the gnathostome β globins were found in pig, tree shrew and scaled reptiles. Phe GH5 is also highly conserved in the β globins, except for the Leu replacement in the β1 globin of five marine gadoid species, gilthead seabream and the Comoran coelacanth, while Cys and Ile were found in burbot and yellow croaker, respectively. Atlantic cod β1 globin showed a Leu/Met polymorphism at position GH5 dominated by the Met variant in northwest-Atlantic populations that was rarely found in northeast-Atlantic cod. Site-specific analyses identified six consensus codons under positive selection, including 122β(GH5), indicating that the amino acid changes identified at this position may offer an adaptive advantage. In fact, computational mutation analysis showed that the replacement of Phe GH5 with Leu or Cys decreased the number of van der Waals contacts essentially in the deoxy form that probably causes a slight increase in the oxygen binding affinity. Conclusions The almost invariant Arg B12 and the AGG codon seem to be important for the packing contacts and pre-mRNA processing, respectively, but the rare mutations identified might be beneficial. The Leu122β1(GH5)Met and Met55β1(D6)Val polymorphisms in Atlantic cod hemoglobin modify the intradimer contacts B12-GH5 and H2-D6, while amino acid replacements at these positions in avian hemoglobin seem to be evolutionary adaptive in air-breathing vertebrates. The results support the theory that adaptive changes in hemoglobin functions are caused by a few substitutions at key positions.
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Ross SD, Behrens JW, Brander K, Methling C, Mork J. Haemoglobin genotypes in cod (Gadus morhua L): Their geographic distribution and physiological significance. Comp Biochem Physiol A Mol Integr Physiol 2013; 166:158-68. [DOI: 10.1016/j.cbpa.2013.05.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/21/2013] [Accepted: 05/24/2013] [Indexed: 11/26/2022]
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8
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Verde C, Giordano D, di Prisco G, Andersen Ø. The haemoglobins of polar fish: evolutionary and physiological significance of multiplicity in Arctic fish. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/14888386.2012.700345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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EVANS MELISSAL, PRAEBEL KIM, PERUZZI STEFANO, BERNATCHEZ LOUIS. Parallelism in the oxygen transport system of the lake whitefish: the role of physiological divergence in ecological speciation. Mol Ecol 2012; 21:4038-50. [DOI: 10.1111/j.1365-294x.2012.05682.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Salvanes AGV, Hart PJ. Is individual variation in competitive performance of reared juvenile cod influenced by haemoglobin genotype? ACTA ACUST UNITED AC 2011. [DOI: 10.1080/00364827.2000.10414578] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Imsland AK, Scanu G, Nævdal G. New variants of the haemoglobins of turbot ( Scophthalmus maximus ): Possible use in population genetics studies and aquaculture. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/00364820308468] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Husebø* Å, Imsland* AK, Nævdal G. Haemoglobin variation in cod: A description of new variants and their geographical distribution. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/00364820410002631] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Bradbury IR, Hubert S, Higgins B, Borza T, Bowman S, Paterson IG, Snelgrove PVR, Morris CJ, Gregory RS, Hardie DC, Hutchings JA, Ruzzante DE, Taggart CT, Bentzen P. Parallel adaptive evolution of Atlantic cod on both sides of the Atlantic Ocean in response to temperature. Proc Biol Sci 2010; 277:3725-34. [PMID: 20591865 DOI: 10.1098/rspb.2010.0985] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Despite the enormous economic and ecological importance of marine organisms, the spatial scales of adaptation and biocomplexity remain largely unknown. Yet, the preservation of local stocks that possess adaptive diversity is critical to the long-term maintenance of productive stable fisheries and ecosystems. Here, we document genomic evidence of range-wide adaptive differentiation in a broadcast spawning marine fish, Atlantic cod (Gadus morhua), using a genome survey of single nucleotide polymorphisms. Of 1641 gene-associated polymorphisms examined, 70 (4.2%) tested positive for signatures of selection using a Bayesian approach. We identify a subset of these loci (n=40) for which allele frequencies show parallel temperature-associated clines (p<0.001, r2=0.89) in the eastern and western north Atlantic. Temperature associations were robust to the statistical removal of geographic distance or latitude effects, and contrasted 'neutral' loci, which displayed no temperature association. Allele frequencies at temperature-associated loci were significantly correlated, spanned three linkage groups and several were successfully annotated supporting the involvement of multiple independent genes. Our results are consistent with the evolution and/or selective sweep of multiple genes in response to ocean temperature, and support the possibility of a new conservation paradigm for non-model marine organisms based on genomic approaches to resolving functional and adaptive diversity.
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Affiliation(s)
- Ian R Bradbury
- Marine Gene Probe Laboratory, Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, Canada, B3H 4J1.
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Methling C, Aluru N, Vijayan MM, Steffensen JF. Effect of moderate hypoxia at three acclimation temperatures on stress responses in Atlantic cod with different haemoglobin types. Comp Biochem Physiol A Mol Integr Physiol 2010; 156:485-90. [PMID: 20388549 DOI: 10.1016/j.cbpa.2010.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 04/04/2010] [Accepted: 04/06/2010] [Indexed: 10/19/2022]
Abstract
This study examines stress responses in Atlantic cod (Gadus morhua) when exposed to a moderate and transient reduction (35% O(2) sat.) in dissolved oxygen at a range of temperatures (5 degrees C, 10 degrees C and 15 degrees C), conditions occurring in some areas they inhabit. Given their geographical distribution pattern, and differences in preferred temperature of cod with different haemoglobin types, the study was extended to include haemoglobin polymorphism. We hypothesised that the differences in temperature preference between HbI-1 and HbI-2 type cod might also be reflected in a difference in stress response to hypoxia exposure. Two hsp70-isoforms (labelled a and b) were detected and they differed in expression in the gills but not in the liver of Atlantic cod. Acclimation temperature significantly affected the expression of hsp70 in the liver, and in an isoform-specific manner in the gills. Hypoxia exposure increased the expression of hsp70 in the liver, but not the gills, of cod and this response was not influenced by the acclimation temperature. The expression of hsp70 in both tissues did not differ between fish with different haemoglobin types. Acclimation temperature significantly impacted plasma cortisol but not lactate levels. Also, acute oxygen limitation or HbI-type significantly elevated plasma cortisol and lactate levels but these responses were not modulated by acclimation temperature. Taken together, our results suggest that both temperature acclimation and acute hypoxic exposure influence the organismal and cellular stress responses in Atlantic cod. We hypothesise that HbI-2 fish are more tolerant to short-term hypoxic episodes than HbI-1 fish, and this adaptation may be independent of tissue hsp70 expression.
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Affiliation(s)
- Caroline Methling
- Marine Biological Laboratory, University of Copenhagen, DK-3000 Helsingør, Denmark.
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Borza T, Stone C, Gamperl AK, Bowman S. Atlantic cod (Gadus morhua) hemoglobin genes: multiplicity and polymorphism. BMC Genet 2009; 10:51. [PMID: 19728884 PMCID: PMC2757024 DOI: 10.1186/1471-2156-10-51] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 09/03/2009] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Hemoglobin (Hb) polymorphism, assessed by protein gel electrophoresis, has been used almost exclusively to characterize the genetic structure of Atlantic cod (Gadus morhua) populations and to establish correlations with phenotypic traits such as Hb oxygen binding capacity, temperature tolerance and growth characteristics. The genetic system used to explain the results of gel electrophoresis entails the presence of one polymorphic locus with two major alleles (HbI-1; HbI-2). However, vertebrates have more than one gene encoding Hbs and recent studies have reported that more than one Hb gene is present in Atlantic cod. These observations prompted us to re-evaluate the number of Hb genes expressed in Atlantic cod, and to perform an in depth search for polymorphisms that might produce relevant phenotypes for breeding programs. RESULTS Analysis of Expressed Sequence Tags (ESTs) led to the identification of nine distinct Hb transcripts; four corresponding to the alpha Hb gene family and five to the beta Hb gene family. To gain insights about the Hb genes encoding these transcripts, genomic sequence data was generated from heterozygous (HbI-1/2) parents and fifteen progeny; five of each HbI type, i.e., HbI-1/1, HbI-1/2 and HbI-2/2. beta Hb genes displayed more polymorphism than alpha Hb genes. Two major allele types (beta1A and beta1B) that differ by two linked non-synonymous substitutions (Met55Val and Lys62Ala) were found in the beta1 Hb gene, and the distribution of these beta1A and beta1B alleles among individuals was congruent with that of the HbI-1 and HbI-2 alleles determined by protein gel electrophoresis. RT-PCR and Q-PCR analysis of the nine Hb genes indicates that all genes are expressed in adult fish, but their level of expression varies greatly; higher expression of almost all Hb genes was found in individuals displaying the HbI-2/2 electrophoretic type. CONCLUSION This study indicates that more Hb genes are present and expressed in adult Atlantic cod than previously documented. Our finding that nine Hb genes are expressed simultaneously in adult fish suggests that Atlantic cod, similarly to fish such as rainbow trout, carp, and goldfish, might be able to respond to environmental challenges such as chronic hypoxia or long-term changes in temperature by altering the level of expression of these genes. In this context, the role of the non-conservative substitution Lys62Ala found in the beta1 Hb gene, which appears to explain the occurrence of the HbI-1 and HbI-2 alleles described by gel electrophoresis, and which was found to be present in other fish such as eel, emerald rockcod, rainbow trout and moray, requires further investigation.
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Affiliation(s)
- Tudor Borza
- Genome Atlantic, NRC Institute for Marine Biosciences, Halifax, NS B3H 3Z1, Canada.
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Gamperl A, Busby C, Hori T, Afonso L, Hall J. Hemoglobin Genotype Has Minimal Influence on the Physiological Response of Juvenile Atlantic Cod (Gadus morhua) to Environmental Challenges. Physiol Biochem Zool 2009; 82:483-94. [DOI: 10.1086/603636] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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NIELSEN EINARE, HEMMER-HANSEN JAKOB, LARSEN PETERFOGED, BEKKEVOLD DORTE. Population genomics of marine fishes: identifying adaptive variation in space and time. Mol Ecol 2009; 18:3128-50. [DOI: 10.1111/j.1365-294x.2009.04272.x] [Citation(s) in RCA: 236] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Andersen O, Wetten OF, De Rosa MC, Andre C, Carelli Alinovi C, Colafranceschi M, Brix O, Colosimo A. Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations. Proc Biol Sci 2009; 276:833-41. [PMID: 19033139 PMCID: PMC2664378 DOI: 10.1098/rspb.2008.1529] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55beta1Val and Lys62beta1Ala are located at crucial positions of the alpha1beta1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55-Ala62 haplotype, while the temperature-insensitive Met55-Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming.
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Affiliation(s)
- Oivind Andersen
- Nofima, 1430 Aas, Norway CIGENE-Centre of Integrative Genetics, 1430 Aas, Norway.
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Johnston IA, Abercromby M, Andersen O. Muscle fibre number varies with haemoglobin phenotype in Atlantic cod as predicted by the optimal fibre number hypothesis. Biol Lett 2008; 2:590-2. [PMID: 17148296 PMCID: PMC1833984 DOI: 10.1098/rsbl.2006.0500] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Atlantic cod (Gadus morhua L.) with the HbI-(2/2) haemoglobin phenotype have a higher blood oxygen affinity at low temperatures and a lower routine metabolic rate than individuals with the HbI-(1/1) phenotype. In the present study, muscle structure was found to be related to haemoglobin phenotype in a coastal population of Atlantic cod from the Saltenfjord region of Northern Norway. The maximum number of fast muscle fibres (FNmax) was reached at approximately 39 cm fork length and was 15% greater in the HbI-(1/1) than in the HbI-(2/2) phenotypes whereas the average fibre diameter for fish of the same fork length was significantly lower. Theoretically, the higher oxygen affinity of the HbI-(2/2) phenotype in the cold water of northern latitudes could have resulted in a relaxation of diffusional constraints at the level of individual muscle fibres, permitting the observed increase in fibre diameter. The results support the optimal fibre number hypothesis which envisages a trade-off between diffusional constraints and the energy cost of maintaining ionic homeostasis with fewer larger diameter muscle fibres in the HbI-(2/2) phenotype contributing to a lower routine metabolic rate.
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Affiliation(s)
- Ian A Johnston
- School of Biology, University of St Andrews, St Andrews, KY16 8LB, UK.
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Hemmer-Hansen J, Nielsen EE, Frydenberg J, Loeschcke V. Adaptive divergence in a high gene flow environment: Hsc70 variation in the European flounder (Platichthys flesus L.). Heredity (Edinb) 2007; 99:592-600. [PMID: 17848973 DOI: 10.1038/sj.hdy.6801055] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Little is known about local adaptations in marine fishes since population genetic surveys in these species have typically not applied genetic markers subject to selection. In this study, we used a candidate gene approach to investigate adaptive population divergence in the European flounder (Platichthys flesus L.) throughout the northeastern Atlantic. We contrasted patterns of genetic variation in a presumably neutral microsatellite baseline to patterns from a heat-shock cognate protein gene, Hsc70. Using two different neutrality tests we found that the microsatellite data set most likely represented a neutral baseline. In contrast, Hsc70 strongly deviated from neutral expectations. Importantly, when estimating standardized levels of population divergence (F(ST)'), we also found a large discrepancy in the patterns of structuring in the two data sets. Thus, samples grouped according to geographical or historical proximity with regards to microsatellites, but according to environmental similarities with regards to Hsc70. The differences between the data sets were particularly pronounced in pairwise comparisons involving populations in the western and central Baltic Sea. For instance, the genetic differentiation between geographically close Baltic Sea and North Sea populations was found to be 0.02 and 0.45 for microsatellites and Hsc70 respectively. Our results strongly suggest adaptive population divergence and indicate local adaptations at the DNA level in a background of high levels of gene flow, typically found in many marine fish species. Furthermore, this study highlights the usefulness of the candidate gene approach for demonstrating local selection in non-model organisms such as most marine fishes.
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Affiliation(s)
- J Hemmer-Hansen
- Department of Ecology and Genetics, University of Aarhus, Aarhus C, Denmark.
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Imsland AK, Foss A, Naevdal G, Johansen T, Stefansson SO, Jonassen TM. New haemoglobin genotypes in Atlantic cod, Gadus morhua: Possible relation with growth. Comp Biochem Physiol A Mol Integr Physiol 2007; 147:955-60. [PMID: 17433886 DOI: 10.1016/j.cbpa.2007.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 03/01/2007] [Accepted: 03/01/2007] [Indexed: 11/21/2022]
Abstract
In a preliminary study, 121 individually tagged juvenile Atlantic cod (Gadus morhua) were classified according to their haemoglobin genotypes into four groups, i.e., two main haemoglobin genotypes [Hb-I(1/2), Hb-I(2/2)] and two sub-types [Hb-I(1/2b), Hb-I(2/2b)], and reared for 3 months at 10 degrees C, 13 degrees C and T-step (fish reared at 16 degrees C and then subsequently moved to 13 and later to 10 degrees C). Overall growth rates across temperatures were 10% and 19% higher in the Hb-I(2/2b), Hb-I(1/2b) sub-types compared to corresponding Hb-I(2/2) and Hb-I(1/2) main types, respectively. Individual growth rate trajectories varied between the genotypes at all temperatures studied. Our study indicates that under certain environmental conditions higher growth in the two sub-types compared to the main genotypes could be expected. This may indicate difference in other physiological characters not studied here, but seen in previous studies, i.e., oxygen affinity and competitive performance.
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Affiliation(s)
- Albert K Imsland
- Akvaplan-niva, Iceland Office, Akralind 4, 201 Kópavogur, Iceland.
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Maruyama K, Yasumasu S, Iuchi I. Evolution of globin genes of the medaka Oryzias latipes (Euteleostei; Beloniformes; Oryziinae). Mech Dev 2005; 121:753-69. [PMID: 15210183 DOI: 10.1016/j.mod.2004.03.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2003] [Revised: 03/11/2004] [Accepted: 03/31/2004] [Indexed: 10/26/2022]
Abstract
Recently we cloned two globin gene clusters from the genome of medaka (Oryzias latipes): one designated the embryonic globin gene cluster (E1; (5')alpha0(3')-(3')beta1(5')-(5')alpha1(3')-(5')beta2(3')-(5')alpha2(3')-(3')alpha3(5')-(5')beta3(3')-(3')beta4(5')-(5')alpha4(3')-(3')psialpha(5')-(5')psibeta(3')) and the other the adult globin gene cluster (A1; (3')ad.alpha1(5')-(5')ad.beta1(3')-(3')ad.alpha2(5')). The E1 and A1 clusters map to linkage groups 8 and 19, respectively. The genes beta1/alpha1, alpha3/beta3, beta4/alpha4, psialpha/psibeta and ad.alpha1/ad.beta1 are organized in head-to-head orientation with respect to transcriptional polarity. The genes alpha0, alpha1 and alpha2 are arranged in tandem with the same orientation. The results suggest that a variety of events occurred in globin gene evolution such as chromosomal translocation, duplication of alpha/beta-paired genes, tandem duplication of single alpha genes and the transformation of one pair of alpha/beta-paired genes into pseudogenes (psialpha/psibeta). Amino acid sequences predicted from the genes were compared with those of 42 alpha and 55 beta teleostean globins using the neighbor-joining or maximum likelihood methods. The phylogenetic trees that were generated classified the teleostean globins into at least four groups, tentatively named 'Embryonic Hb Group (I)', 'Notothenioid Major Adult Hb Group (II)', 'Anodic Adult Hb Group (III)' and 'Cathodic Adult Hb Group (IV)'. The medaka genes alpha0, beta1, alpha1, alpha2, alpha3, beta3, beta4 and alpha4 belong to group I, and ad.alpha1 and ad.beta1 to group II. Further analysis suggests that psialpha/psibeta and beta2/ad.alpha2 belong to groups III and IV, respectively. Thus, globin genes in the medaka probably were diversified from four ancestral genes, one for each group. On the basis of the gene comparisons, we present a hypothetical pathway for globin gene evolution in the medaka.
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Affiliation(s)
- Kouichi Maruyama
- Life Science Institute, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan
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Blood‐Gas Transport and Hemoglobin Function in Polar Fishes: Does Low Temperature Explain Physiological Characters? ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s1546-5098(04)22007-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Brix O, Thorkildsen S, Colosimo A. Temperature acclimation modulates the oxygen binding properties of the Atlantic cod (Gadus morhua L.) genotypes—HbI*1/1, HbI*1/2, and HbI*2/2—by changing the concentrations of their major hemoglobin components (results from growth studies at different temperatures). Comp Biochem Physiol A Mol Integr Physiol 2004; 138:241-51. [PMID: 15275659 DOI: 10.1016/j.cbpb.2004.04.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2004] [Revised: 04/22/2004] [Accepted: 04/24/2004] [Indexed: 11/21/2022]
Abstract
The influence of long-term acclimation temperatures in Atlantic cod (Gadus morhua) was studied by growth experiments carried out over a total of 272 individuals. The attention focused on the structural and functional modulation of the five electrophoretically distinguishable genotypes of cod hemoglobin (HbI*1/1, HbI*1/2, HbI*2/2, HbI*1/2b, and HbI*2/2b) and on the correlation with body length/weight. The main results can be summarized as follows. (1) Acclimation to lower (4 and 8 degrees C) and higher (12 and 15 degrees C) temperatures favors the expression of, respectively, more anodic and more cathodic hemoglobin components. (2) The optimal O(2) transporting features are observed at 12 degrees C, as well as a saturation-dependent temperature dependence of O(2) binding, which furthermore is strongly dependent upon the acclimation background. (3) The optimal growth condition for the three main genotypes (HbI*1/1, HbI*1/2, and HbI*2/2) is associated with T=12 degrees C. The overall results are consistent with the idea that environmental temperatures constitute a primary factor in the aggregation of individuals physiologically more than genetically homogeneous. This is fully confirmed by careful statistical analysis carried out over a subset of individuals for which the full set of structural (isoelectric focusing), functional (O(2) binding), and growth data was available.
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Affiliation(s)
- Ole Brix
- Department of Zoology, University of Bergen, Thormhlensgate 55.3, Bergen N5020, Norway.
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Petersen MF, Steffensen JF. Preferred temperature of juvenile Atlantic cod Gadus morhua with different haemoglobin genotypes at normoxia and moderate hypoxia. J Exp Biol 2003; 206:359-64. [PMID: 12477905 DOI: 10.1242/jeb.00111] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Atlantic cod Gadus morhua has polymorphic haemoglobin, which can be separated into two homozygous types, HbI-1 and HbI-2, and one heterozygous type HbI-1/2. The geographical distribution of Atlantic cod with the different haemoglobin types varies, with the HbI(2) allele occurring at high frequency in northern regions, and the HbI(1) allele dominant in warmer areas. To determine if temperature is a selective parameter in the distribution of the haemoglobin types, the preferred temperature of the homozygous genotypes HbI-1 and HbI-2 was measured. We found that HbI-2 cod preferred a temperature of 8.2+/-1.5 degrees C while HbI-1 cod preferred 15.4+/-1.1 degrees C, and this preference was significant. The effect of hypoxia (35% oxygen saturation) on the preferred temperature was also measured. Previous studies showed that the preferred temperature of fish decreases during hypoxia, and this was the case for HbI-1 cod, which preferred 9.8+/-1.8 degrees C during hypoxia, whereas HbI-2 cod did not show this effect. The results indicate that environmental temperature changes will lead to a distributional change in the different haemoglobin types of Atlantic cod, global warming providing an advantage for HbI-1 cod. However, since HbI-1 cod prefer a low temperature under hypoxic conditions, a combination of increased water temperature and hypoxia could be unfavourable for Atlantic cod stocks.
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Affiliation(s)
- Maria Faldborg Petersen
- Marine Biological Laboratory, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark.
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An ecophysiological interpretation of hemoglobin multiplicity in three herbivorous marine teleost species from New Zealand. Comp Biochem Physiol A Mol Integr Physiol 1998. [DOI: 10.1016/s1095-6433(98)10121-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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