1
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Tanner RL, Gleason LU, Dowd WW. Environment-driven shifts in inter-individual variation and phenotypic integration within subnetworks of the mussel transcriptome and proteome. Mol Ecol 2022; 31:3112-3127. [PMID: 35363903 PMCID: PMC9321163 DOI: 10.1111/mec.16452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 03/18/2022] [Accepted: 03/28/2022] [Indexed: 11/28/2022]
Abstract
The environment can alter the magnitude of phenotypic variation among individuals, potentially influencing evolutionary trajectories. However, environmental influences on variation are complex and remain understudied. Populations in heterogeneous environments might exhibit more variation, the amount of variation could differ between benign and stressful conditions, and/or variation might manifest in different ways among stages of the gene‐to‐protein expression cascade or among physiological functions. Here, we explore these three issues by quantifying patterns of inter‐individual variation in both transcript and protein expression levels among California mussels, Mytilus californianus Conrad. Mussels were exposed to five ecologically relevant treatments that varied in the mean and interindividual heterogeneity of body temperature. To target a diverse set of physiological functions, we assessed variation within 19 expression subnetworks, including canonical stress‐response pathways and empirically derived coexpression clusters that represent a diffuse set of cellular processes. Variation in expression was particularly pronounced in the treatments with high mean and heterogeneous body temperatures. However, with few exceptions, environment‐dependent shifts of variation in the transcriptome were not reflected in the proteome. A metric of phenotypic integration provided evidence for a greater degree of constraint on relative expression levels (i.e., stronger correlation) within expression subnetworks in benign, homogeneous environments. Our results suggest that environments that are more stressful on average – and which also tend to be more heterogeneous – can relax these expression constraints and reduce phenotypic integration within biochemical subnetworks. Context‐dependent “unmasking” of functional variation may contribute to interindividual differences in physiological phenotype and performance in stressful environments.
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Affiliation(s)
- Richelle L Tanner
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA.,Environmental Science & Policy Program, Chapman University, Orange, CA, 92866, USA
| | - Lani U Gleason
- Department of Biological Sciences, California State University, Sacramento, Sacramento, CA, 95819, USA
| | - W Wesley Dowd
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
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2
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Madeira D, Fernandes JF, Jerónimo D, Ricardo F, Santos A, Domingues MR, Calado R. Calcium homeostasis and stable fatty acid composition underpin heatwave tolerance of the keystone polychaete Hediste diversicolor. ENVIRONMENTAL RESEARCH 2021; 195:110885. [PMID: 33609552 DOI: 10.1016/j.envres.2021.110885] [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: 01/05/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Extreme weather events, such as heatwaves, are becoming increasingly frequent, long-lasting and severe as global climate change continues, shaping marine biodiversity patterns worldwide. Increased risk of overheating and mortality across major taxa have been recurrently observed, jeopardizing the sustainability of ecosystem services. Molecular responses of species, which scale up to physiological and population responses, are determinant processes that modulate species sensitivity or tolerance to extreme weather events. Here, by integrating proteomic, fatty acid profiling and physiological approaches, we show that the tolerance of the intertidal ragworm Hediste diversicolor, a keystone species in estuarine ecosystems and an emergent blue bio-resource, to long-lasting heatwaves (24 vs 30 °C for 30 days) is shaped by calcium homeostasis, immune function and stability of fatty acid profiles. These features potentially enabled H. diversicolor to increase its thermal tolerance limit by 0.81 °C under the heatwave scenario and maintain survival. No growth trade-offs were detected, as wet weight remained stable across conditions. Biological variation of physiological parameters was lower when compared to molecular measures. Proteins showed an overall elevated coefficient of variation, although decreasing molecular variance under the heatwave scenario was observed for both proteins and fatty acids. This finding is consistent with the phenomenon of physiological canalization in extreme environments and contradicts the theory that novel conditions increase trait variation. Our results show that keystone highly valued marine polychaetes are tolerant to heatwaves, confirming the potential of H. diversicolor as a blue bio-resource and opening new avenues for sustainable marine aquaculture development.
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Affiliation(s)
- Diana Madeira
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal; UCIBIO, REQUIMTE, Department of Chemistry, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516, Caparica, Portugal; University of Quebec in Rimouski (UQAR), Department of Biology, Chemistry and Geography, 300 Allée des Ursulines, Rimouski, QC, G5L 3A1, Canada.
| | - Joana Filipa Fernandes
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal
| | - Daniel Jerónimo
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal
| | - Fernando Ricardo
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal
| | - Andreia Santos
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal
| | - Maria Rosário Domingues
- Mass Spectrometry Centre, LAQV REQUIMTE, Department of Chemistry, University of Aveiro, Santiago University Campus, 3810-193, Aveiro, Portugal; ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Santiago University Campus, 3810-193, Aveiro, Portugal
| | - Ricardo Calado
- ECOMARE-Laboratory for Innovation and Sustainability of Marine Biological Resources, CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada Do Porto de Pesca Costeira, 3830-565, Gafanha da Nazaré, Portugal.
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3
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Madeira D, Araújo JE, Madeira C, Mendonça V, Vitorino R, Vinagre C, Diniz MS. Seasonal proteome variation in intertidal shrimps under a natural setting: Connecting molecular networks with environmental fluctuations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:134957. [PMID: 31767328 DOI: 10.1016/j.scitotenv.2019.134957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
The ability of intertidal organisms to maintain their performance via molecular and physiological adjustments under low tide, seasonal fluctuations and extreme events ultimately determines population viability. Analyzing this capacity in the wild is extremely relevant since intertidal communities are under increased climate variability owing to global changes. We addressed the seasonal proteome signatures of a key intertidal species, the shrimp Palaemon elegans, in a natural setting. Shrimps were collected during spring and summer seasons at low tides and were euthanized in situ. Environmental variability was also assessed using hand-held devices and data loggers. Muscle samples were taken for 2D gel electrophoresis and protein identification through mass spectrometry. Proteome data revealed that 55 proteins (10.6% of the proteome) significantly changed between spring and summer collected shrimps, 24 of which were identified. These proteins were mostly involved in cytoskeleton remodelling, energy metabolism and transcription regulation. Overall, shrimps modulate gene expression leading to metabolic and structural adjustments related to seasonal differences in the wild (i.e. abiotic variation and possibly intrinsic cycles of reproduction and growth). This potentially promotes performance and fitness as suggested by the higher condition index in summer-collected shrimps. However, inter-individual variation (% coefficient of variation) in protein levels was quite low (min-max ranges were 0.6-8.3% in spring and 1.2-4.8% in summer), possibly suggesting reduced genetic diversity or physiological canalization. Protein plasticity is relevant to cope with present and upcoming environmental variation related to anthropogenic forcing (e.g. global change, pollution) but low inter-individual variation may limit evolutionary potential of shrimp populations.
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Affiliation(s)
- D Madeira
- Research Unit on Applied Molecular Biosciences (UCIBIO-REQUIMTE), Department of Chemistry, Faculty of Sciences and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal; Centre for Environmental and Marine Studies (CESAM), ECOMARE & Department of Biology, University of Aveiro, Estrada do Porto de Pesca, 3830-565 Gafanha da Nazaré, Portugal.
| | - J E Araújo
- Research Unit on Applied Molecular Biosciences (UCIBIO-REQUIMTE), Department of Chemistry, Faculty of Sciences and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal
| | - C Madeira
- Research Unit on Applied Molecular Biosciences (UCIBIO-REQUIMTE), Department of Chemistry, Faculty of Sciences and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal; Marine and Environmental Sciences Centre (MARE), Department of Biology, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisboa, Portugal
| | - V Mendonça
- Marine and Environmental Sciences Centre (MARE), Department of Biology, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisboa, Portugal
| | - R Vitorino
- Institute for Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; Cardiovascular Research Centre (UnIC), Department of Cardiothoracic Surgery and Physiology, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
| | - C Vinagre
- Marine and Environmental Sciences Centre (MARE), Department of Biology, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisboa, Portugal
| | - M S Diniz
- Research Unit on Applied Molecular Biosciences (UCIBIO-REQUIMTE), Department of Chemistry, Faculty of Sciences and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal.
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4
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Evans TG, Logan CA. Mechanisms of biological sensitivity and resistance to a rapidly changing ocean. Comp Biochem Physiol A Mol Integr Physiol 2019; 241:110625. [PMID: 31790807 DOI: 10.1016/j.cbpa.2019.110625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tyler G Evans
- Department of Biological Sciences, California State University East Bay, 25800 Carlos Bee Blvd, Hayward, CA 94542, USA.
| | - Cheryl A Logan
- Department of Marine Science, California State University Monterey Bay, 100 Campus Center, Seaside, CA 93955, USA
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5
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Tanner RL, Dowd WW. Inter-individual physiological variation in responses to environmental variation and environmental change: Integrating across traits and time. Comp Biochem Physiol A Mol Integr Physiol 2019; 238:110577. [PMID: 31521705 DOI: 10.1016/j.cbpa.2019.110577] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 10/26/2022]
Abstract
Greater understanding of physiological responses to climate change demands deeper comprehension of the causes and consequences of physiological variation. Increasingly, population trait means are being deconstructed into variable signals at the level of individuals. We advocate for greater consideration of such inter-individual physiological variation and how it both depends on and interacts with environmental variability. First, we review several studies on the intertidal mussel Mytilus californianus to illustrate how the magnitude of inter-individual variation may depend on the environmental context analyzed (i.e., is the mean condition benign or stressful?) and/or on the specific physiological metric investigated. Stressful conditions may reveal or mask variation in disparate ways at different levels of analysis (e.g., transcriptome vs. proteome), but we often lack crucial information regarding the relationships among these different physiological metrics and their consequences for fitness. We then reanalyze several published datasets to ask whether individuals employ divergent strategies over time in response to acute heat stress; such time-dependence would further complicate interpretation of physiological variation. However, definitive conclusions are precluded by limited sample sizes and short timescales in extant datasets. A key remaining challenge is to extend these analytical frameworks to longer periods over which individuals in a population experience repeated, but spatially variable, episodic stress events. We conclude that variation at multiple levels of analysis should be investigated over longer periods and, where possible, within individuals (or genotypes) experiencing repeated environmental challenges. Although difficult in practice, such studies will facilitate improved understanding of potential population-level physiological responses to climate change.
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Affiliation(s)
- Richelle L Tanner
- Washington State University, School of Biological Sciences, P.O. Box 644236, Pullman, WA 99164-4236, USA.
| | - W Wesley Dowd
- Washington State University, School of Biological Sciences, P.O. Box 644236, Pullman, WA 99164-4236, USA
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6
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Baris TZ, Wagner DN, Dayan DI, Du X, Blier PU, Pichaud N, Oleksiak MF, Crawford DL. Evolved genetic and phenotypic differences due to mitochondrial-nuclear interactions. PLoS Genet 2017; 13:e1006517. [PMID: 28362806 PMCID: PMC5375140 DOI: 10.1371/journal.pgen.1006517] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 12/01/2016] [Indexed: 02/05/2023] Open
Abstract
The oxidative phosphorylation (OxPhos) pathway is responsible for most aerobic ATP production and is the only pathway with both nuclear and mitochondrial encoded proteins. The importance of the interactions between these two genomes has recently received more attention because of their potential evolutionary effects and how they may affect human health and disease. In many different organisms, healthy nuclear and mitochondrial genome hybrids between species or among distant populations within a species affect fitness and OxPhos functions. However, what is less understood is whether these interactions impact individuals within a single natural population. The significance of this impact depends on the strength of selection for mito-nuclear interactions. We examined whether mito-nuclear interactions alter allele frequencies for ~11,000 nuclear SNPs within a single, natural Fundulus heteroclitus population containing two divergent mitochondrial haplotypes (mt-haplotypes). Between the two mt-haplotypes, there are significant nuclear allele frequency differences for 349 SNPs with a p-value of 1% (236 with 10% FDR). Unlike the rest of the genome, these 349 outlier SNPs form two groups associated with each mt-haplotype, with a minority of individuals having mixed ancestry. We use this mixed ancestry in combination with mt-haplotype as a polygenic factor to explain a significant fraction of the individual OxPhos variation. These data suggest that mito-nuclear interactions affect cardiac OxPhos function. The 349 outlier SNPs occur in genes involved in regulating metabolic processes but are not directly associated with the 79 nuclear OxPhos proteins. Therefore, we postulate that the evolution of mito-nuclear interactions affects OxPhos function by acting upstream of OxPhos.
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Affiliation(s)
- Tara Z. Baris
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
- * E-mail:
| | - Dominique N. Wagner
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
| | - David I. Dayan
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
| | - Xiao Du
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
| | - Pierre U. Blier
- Dept de Biologie, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Quebec, Canada
| | - Nicolas Pichaud
- Dept de Biologie, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Quebec, Canada
| | - Marjorie F. Oleksiak
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
| | - Douglas L. Crawford
- Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Rickenbacker Causeway, Miami, FL, United States of America
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7
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Chiarello C, Vazquez D, Felton A, McDowell A. Structural asymmetry of the human cerebral cortex: Regional and between-subject variability of surface area, cortical thickness, and local gyrification. Neuropsychologia 2016; 93:365-379. [PMID: 26792368 DOI: 10.1016/j.neuropsychologia.2016.01.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 12/07/2015] [Accepted: 01/11/2016] [Indexed: 10/22/2022]
Abstract
Structural asymmetry varies across individuals, brain regions, and metrics of cortical organization. The current study investigated regional differences in asymmetry of cortical surface area, thickness, and local gyrification, and the extent of between-subject variability in these metrics, in a sample of healthy young adults (N=200). Between-subject variability in cortical structure may provide a means to assess the extent of biological flexibility or constraint of brain regions, and we explored the potential influence of this variability on the phenotypic expression of structural asymmetry. The findings demonstrate that structural asymmetries are nearly ubiquitous across the cortex, with differing regional organization for the three cortical metrics. This implies that there are multiple, only partially overlapping, maps of structural asymmetry. The results further indicate that the degree of asymmetry of a brain region can be predicted by the extent of the region's between-subject variability. These findings provide evidence that reduced biological constraint promotes the expression of strong structural asymmetry.
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8
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Norin T, Malte H, Clark TD. Differential plasticity of metabolic rate phenotypes in a tropical fish facing environmental change. Funct Ecol 2015. [DOI: 10.1111/1365-2435.12503] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tommy Norin
- Australian Institute of Marine Science PMB 3 Townsville MC Queensland4810 Australia
- Zoophysiology Department of Bioscience Aarhus University DK‐8000 Aarhus C Denmark
| | - Hans Malte
- Zoophysiology Department of Bioscience Aarhus University DK‐8000 Aarhus C Denmark
| | - Timothy D. Clark
- Australian Institute of Marine Science PMB 3 Townsville MC Queensland4810 Australia
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9
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Shaw JR, Hampton TH, King BL, Whitehead A, Galvez F, Gross RH, Keith N, Notch E, Jung D, Glaholt SP, Chen CY, Colbourne JK, Stanton BA. Natural selection canalizes expression variation of environmentally induced plasticity-enabling genes. Mol Biol Evol 2014; 31:3002-15. [PMID: 25158801 PMCID: PMC4209136 DOI: 10.1093/molbev/msu241] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Many organisms survive fluctuating and extreme environmental conditions by manifesting multiple distinct phenotypes during adulthood by means of developmental processes that enable phenotypic plasticity. We report on the discovery of putative plasticity-enabling genes that are involved in transforming the gill of the euryhaline teleost fish, Fundulus heteroclitus, from its freshwater to its seawater gill-type, a process that alters both morphology and function. Gene expression that normally enables osmotic plasticity is inhibited by arsenic. Gene sets defined by antagonistic interactions between arsenic and salinity show reduced transcriptional variation among individual fish, suggesting unusually accurate and precise regulatory control of these genes, consistent with the hypothesis that they participate in a canalized developmental response. We observe that natural selection acts to preserve canalized gene expression in populations of killifish that are most tolerant to abrupt salinity change and that these populations show the least variability in their transcription of genes enabling plasticity of the gill. We found that genes participating in this highly canalized and conserved plasticity-enabling response had significantly fewer and less complex associations with transcriptional regulators than genes that respond only to arsenic or salinity. Collectively these findings, which are drawn from the relationships between environmental challenge, plasticity, and canalization among populations, suggest that the selective processes that facilitate phenotypic plasticity do so by targeting the regulatory networks that gives rise to the response. These findings also provide a generalized, conceptual framework of how genes might interact with the environment and evolve toward the development of plastic traits.
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Affiliation(s)
- Joseph R Shaw
- The School of Public and Environmental Affairs, Indiana University, Bloomington The Center for Genomics and Bioinformatics, Indiana University, Bloomington The Mount Desert Island Biological Laboratory, Salisbury Cove, ME Environmental Genomics Group, School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Thomas H Hampton
- Environmental Genomics Group, School of Biosciences, University of Birmingham, Birmingham, United Kingdom Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Benjamin L King
- The Mount Desert Island Biological Laboratory, Salisbury Cove, ME
| | - Andrew Whitehead
- Department of Environmental Toxicology, University of California, Davis
| | - Fernando Galvez
- Department of Biological Sciences, Louisiana State University, Baton Rouge
| | - Robert H Gross
- Department of Biological Sciences, Dartmouth College, Hanover, NH
| | - Nathan Keith
- The School of Public and Environmental Affairs, Indiana University, Bloomington
| | - Emily Notch
- The Mount Desert Island Biological Laboratory, Salisbury Cove, ME Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Dawoon Jung
- The Mount Desert Island Biological Laboratory, Salisbury Cove, ME Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Stephen P Glaholt
- The School of Public and Environmental Affairs, Indiana University, Bloomington
| | - Celia Y Chen
- Department of Biological Sciences, Dartmouth College, Hanover, NH
| | - John K Colbourne
- The Center for Genomics and Bioinformatics, Indiana University, Bloomington The Mount Desert Island Biological Laboratory, Salisbury Cove, ME Environmental Genomics Group, School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Bruce A Stanton
- The Mount Desert Island Biological Laboratory, Salisbury Cove, ME Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH
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10
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Schulte PM. What is environmental stress? Insights from fish living in a variable environment. ACTA ACUST UNITED AC 2014; 217:23-34. [PMID: 24353201 DOI: 10.1242/jeb.089722] [Citation(s) in RCA: 165] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Although the term environmental stress is used across multiple fields in biology, the inherent ambiguity associated with its definition has caused confusion when attempting to understand organismal responses to environmental change. Here I provide a brief summary of existing definitions of the term stress, and the related concepts of homeostasis and allostasis, and attempt to unify them to develop a general framework for understanding how organisms respond to environmental stressors. I suggest that viewing stressors as environmental changes that cause reductions in performance or fitness provides the broadest and most useful conception of the phenomenon of stress. I examine this framework in the context of animals that have evolved in highly variable environments, using the Atlantic killifish, Fundulus heteroclitus, as a case study. Consistent with the extreme environmental variation that they experience in their salt marsh habitats, killifish have substantial capacity for both short-term resistance and long-term plasticity in the face of changing temperature, salinity and oxygenation. There is inter-population variation in the sensitivity of killifish to environmental stressors, and in their ability to acclimate, suggesting that local adaptation can shape the stress response even in organisms that are broadly tolerant and highly plastic. Whole-organism differences between populations in stressor sensitivity and phenotypic plasticity are reflected at the biochemical and molecular levels in killifish, emphasizing the integrative nature of the response to environmental stressors. Examination of this empirical example highlights the utility of using an evolutionary perspective on stressors, stress and stress responses.
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Affiliation(s)
- Patricia M Schulte
- Department of Zoology, 6270 University Blvd, University of British Columbia, Vancouver, BC, V6T 1Z4 Canada
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11
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Seebacher F, Beaman J, Little AG. Regulation of thermal acclimation varies between generations of the short-lived mosquitofish that developed in different environmental conditions. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12156] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Frank Seebacher
- School of Biological Sciences A08; University of Sydney; Sydney New South Wales 2006 Australia
| | - Julian Beaman
- School of Biological Sciences A08; University of Sydney; Sydney New South Wales 2006 Australia
| | - Alexander G. Little
- School of Biological Sciences A08; University of Sydney; Sydney New South Wales 2006 Australia
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