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Elbassiouny AA, Buck LT, Abatti LE, Mitchell JA, Crampton WGR, Lovejoy NR, Chang BSW. Evolution of a novel regulatory mechanism of hypoxia inducible factor in hypoxia-tolerant electric fishes. J Biol Chem 2024; 300:105727. [PMID: 38325739 PMCID: PMC10958119 DOI: 10.1016/j.jbc.2024.105727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/25/2024] [Accepted: 02/01/2024] [Indexed: 02/09/2024] Open
Abstract
Hypoxia is a significant source of metabolic stress that activates many cellular pathways involved in cellular differentiation, proliferation, and cell death. Hypoxia is also a major component in many human diseases and a known driver of many cancers. Despite the challenges posed by hypoxia, there are animals that display impressive capacity to withstand lethal levels of hypoxia for prolonged periods of time and thus offer a gateway to a more comprehensive understanding of the hypoxic response in vertebrates. The weakly electric fish genus Brachyhypopomus inhabits some of the most challenging aquatic ecosystems in the world, with some species experiencing seasonal anoxia, thus providing a unique system to study the cellular and molecular mechanisms of hypoxia tolerance. In this study, we use closely related species of Brachyhypopomus that display a range of hypoxia tolerances to probe for the underlying molecular mechanisms via hypoxia inducible factors (HIFs)-transcription factors known to coordinate the cellular response to hypoxia in vertebrates. We find that HIF1⍺ from hypoxia tolerant Brachyhypopomus species displays higher transactivation in response to hypoxia than that of intolerant species, when overexpressed in live cells. Moreover, we identified two SUMO-interacting motifs near the oxygen-dependent degradation and transactivation domains of the HIF1⍺ protein that appear to boost transactivation of HIF1, regardless of the genetic background. Together with computational analyses of selection, this shows that evolution of HIF1⍺ are likely to underlie adaptations to hypoxia tolerance in Brachyhypopomus electric fishes, with changes in two SUMO-interacting motifs facilitating the mechanism of this tolerance.
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Affiliation(s)
- Ahmed A Elbassiouny
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.
| | - Leslie T Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Luis E Abatti
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Jennifer A Mitchell
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | | | - Nathan R Lovejoy
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada; Department of Biological Sciences, University of Toronto Scarborough, Scarborough, Ontario, Canada
| | - Belinda S W Chang
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada.
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Endress MGA, Penn JL, Boag TH, Burford BP, Sperling EA, Deutsch CA. Thermal optima in the hypoxia tolerance of marine ectotherms: Physiological causes and biogeographic consequences. PLoS Biol 2024; 22:e3002443. [PMID: 38227580 PMCID: PMC10790991 DOI: 10.1371/journal.pbio.3002443] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 11/21/2023] [Indexed: 01/18/2024] Open
Abstract
The minimum O2 needed to fuel the demand of aquatic animals is commonly observed to increase with temperature, driven by accelerating metabolism. However, recent measurements of critical O2 thresholds ("Pcrit") reveal more complex patterns, including those with a minimum at an intermediate thermal "optimum". To discern the prevalence, physiological drivers, and biogeographic manifestations of such curves, we analyze new experimental and biogeographic data using a general dynamic model of aquatic water breathers. The model simulates the transfer of oxygen from ambient water through a boundary layer and into animal tissues driven by temperature-dependent rates of metabolism, diffusive gas exchange, and ventilatory and circulatory systems with O2-protein binding. We find that a thermal optimum in Pcrit can arise even when all physiological rates increase steadily with temperature. This occurs when O2 supply at low temperatures is limited by a process that is more temperature sensitive than metabolism, but becomes limited by a less sensitive process at warmer temperatures. Analysis of published species respiratory traits suggests that this scenario is not uncommon in marine biota, with ventilation and circulation limiting supply under cold conditions and diffusion limiting supply at high temperatures. Using occurrence data, we show that species with these physiological traits inhabit lowest O2 waters near the optimal temperature for hypoxia tolerance and are restricted to higher O2 at temperatures above and below this optimum. Our results imply that hypoxia tolerance can decline under both cold and warm conditions and thus may influence both poleward and equatorward species range limits.
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Affiliation(s)
- Martin-Georg A. Endress
- School of Oceanography, University of Washington, Seattle, Washington, United States of America
- Institute of Zoology, University of Cologne, Cologne, Germany
| | - Justin L. Penn
- School of Oceanography, University of Washington, Seattle, Washington, United States of America
- Department of Geosciences, Princeton University, Princeton, New Jersey, United States of America
| | - Thomas H. Boag
- Department of Geosciences, Princeton University, Princeton, New Jersey, United States of America
| | - Benjamin P. Burford
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center, Santa Cruz, California, United States of America
| | - Erik A. Sperling
- Department of Earth and Planetary Sciences, Stanford University, Stanford, California, United States of America
| | - Curtis A. Deutsch
- School of Oceanography, University of Washington, Seattle, Washington, United States of America
- Department of Geosciences, Princeton University, Princeton, New Jersey, United States of America
- High Meadows Environmental Institute, Princeton University, Princeton, New Jersey, United States of America
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3
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The chromosome-level genome and key genes associated with mud-dwelling behavior and adaptations of hypoxia and noxious environments in loach (Misgurnus anguillicaudatus). BMC Biol 2023; 21:18. [PMID: 36726103 PMCID: PMC9893644 DOI: 10.1186/s12915-023-01517-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 01/18/2023] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND The loach (Misgurnus anguillicaudatus), the most widely distributed species of the family Cobitidae, displays a mud-dwelling behavior and intestinal air-breathing, inhabiting the muddy bottom of extensive freshwater habitats. However, lack of high-quality reference genome seriously limits the interpretation of the genetic basis of specialized adaptations of the loach to the adverse environments including but not limited to the extreme water temperature, hypoxic and noxious mud environment. RESULTS This study generated a 1.10-Gb high-quality, chromosome-anchored genome assembly, with a contig N50 of 3.83 Mb. Multiple comparative genomic analyses found that proto-oncogene c-Fos (fos), a regulator of bone development, is positively selected in loach. Knockout of fos (ID: Mis0086400.1) led to severe osteopetrosis and movement difficulties, combined with the comparison results of bone mineral density, supporting the hypothesis that fos is associated with loach mud-dwelling behavior. Based on genomic and transcriptomic analysis, we identified two key elements involved in the intestinal air-breathing of loach: a novel gene (ID: mis0158000.1) and heat shock protein beta-1 (hspb1). The flavin-containing monooxygenase 5 (fmo5) genes, central to xenobiotic metabolism, undergone expansion in loach and were identified as differentially expressed genes in a drug stress trial. A fmo5-/- (ID: Mis0185930.1) loach displayed liver and intestine injury, indicating the importance of this gene to the adaptation of the loach to the noxious mud. CONCLUSIONS Our work provides valuable insights into the genetic basis of biological adaptation to adverse environments.
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Ouyang P, Ren Y, Zhou Y, Li Q, Huang X, Chen D, Geng Y, Guo H, Fang J, Deng H, Lai W, Chen Z, Shu G, Yin L. Characteristics of pathology and transcriptome profiling reveal features of immune response of acutely infected and asymptomatic infected of carp edema virus in Koi. Front Immunol 2023; 14:1142830. [PMID: 36923401 PMCID: PMC10009185 DOI: 10.3389/fimmu.2023.1142830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/06/2023] [Indexed: 03/02/2023] Open
Abstract
Koi sleepy disease (KSD) is a high mortality and infection viral disease caused by carp edema virus (CEV), which was a serious threat to aquaculture of common carp and export trade of Koi worldwide. Asymptomatic infection is an important cause of the difficulty in preventing KSD and its worldwide spread, because asymptomatic infection can be activated under appropriate condition. However, the understanding of the molecular correlates of these infections is still unknown. The purpose of this study was to compare the pathology change, enzyme activity, immunoglobulin activity, host and viral gene expression differences in acutely infected and cohabiting asymptomatic Koi infected with CEV. Healthy Koi were used as a control. The gross pathology, histopathology and ultrastructural pathology showed the difference and characteristics damage to the tissues of Koi under different infection conditions. Periodic Acid-Schiff stain (PAS), enzyme activity and immunoglobulin activity revealed changes in the immune response of gill tissue between acutely infected, asymptomatic infected and healthy Koi. A total of 111 and 2484 upregulated genes and 257 and 4940 downregulated genes were founded in healthy Koi vs asymptomatic infected Koi and healthy Koi vs acutely infected Koi, respectively. Additionally, 878 upregulated genes and 1089 downregulated genes were identified in asymptomatic vs. acutely infected Koi. Immune gene categories and their corresponding genes in different comparison groups were revealed. A total of 3, 59 and 28 immune-related genes were identified in the group of healthy Koi vs asymptomatic infected Koi, healthy Koi vs acutely infected Koi and asymptomatic infected Koi vs acutely infected Koi, respectively. Nineteen immune-related genes have the same expression manner both in healthy Koi vs acutely infected Koi and asymptomatic Koi vs acutely infected Koi, while 9 immune-related genes were differentially expressed only in asymptomatic Koi vs acutely infected Koi, which may play a role in viral reactivation. In addition, 8 differentially expressed genes (DEGs) were validated by quantitative reverse transcription PCR (RT-qPCR), and the results were consistent with the RNA-Seq results. In conclusion, the data obtained in this study provide new evidence for further elucidating CEV-host interactions and the CEV infection mechanism and will facilitate the implementation of integrated strategies for controlling CEV infection and spread.
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Affiliation(s)
- Ping Ouyang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yongqiang Ren
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yongheng Zhou
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qiunan Li
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiaoli Huang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Defang Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yi Geng
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Hongrui Guo
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jing Fang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Huidan Deng
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Weiming Lai
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Zhengli Chen
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Gang Shu
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Lizi Yin
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
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Kämmer N, Erdinger L, Braunbeck T. The onset of active gill respiration in post-embryonic zebrafish (Danio rerio) larvae triggers an increased sensitivity to neurotoxic compounds. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 249:106240. [PMID: 35863251 DOI: 10.1016/j.aquatox.2022.106240] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Originally designed as a general alternative to acute fish toxicity testing (AFT), the fish embryo toxicity test (FET) has become subject to concerns with respect to neurotoxic substances. Whereas oxygen uptake in the fish embryo primarily occurs via diffusion across the skin, juvenile and adult fish rely on active ventilation of the gills. As a consequence, substances including, e.g., neurotoxicants which prevent appropriate ventilation of gills ("respiratory failure syndrome") might lead to suffocation in juvenile and adult fish, but not in skin-breathing embryos. To investigate if this respiratory failure syndrome might play a role for the higher sensitivity of juvenile and adult fish to neurotoxicants, a modified acute toxicity test using post-embryonic, early gill-breathing life-stages of zebrafish was developed with chlorpyrifos, permethrin, lindane, aldicarb, ziram and aniline as test substances. Additionally, a comparative study into bioaccumulation of lipophilic substances with logKow > 3.5 and swimbladder deflation as potential side effects of the respiratory failure syndrome was performed with 4 d old skin-breathing and 12 d old gill-breathing zebrafish. With respect to acute toxicity, post-embryonic 12 d larvae proved to be more sensitive than both embryos (FET) and adult zebrafish (AFT) to all test substances except for permethrin. Accumulation of chlorpyrifos, lindane and permethrin was 1.3- to 5-fold higher in 4 d old than in 12 d old zebrafish, suggesting that (intermediate) storage of substances in the yolk might reduce bioavailability and prevent metabolization, which could be a further reason for lower toxicity in 4 d than in 12 d old zebrafish. Whereas ziram and aniline showed no significant effect on the swimbladder, zebrafish exposed to chlorpyrifos, lindane and permethrin showed significantly deflated swimbladders in 12 d old larvae; in the case of aldicarb, there was a significant hyperinflation in 4 d old larvae. Swimbladder deflation in post-embryonic 12 d zebrafish larvae might be hypothesized as a reason for a lack of internal oxygen supplies during the respiratory failure syndrome, whereas in 4 d old embryos cholinergic hyperinflation of the swimbladder dominates over other effects. Regarding acute lethality, the study provides further evidence that the switch from transcutaneous to branchial respiration in post-embryonic zebrafish life-stages might be the reason for the higher sensitivity of juvenile and adult fish to neurotoxic substances.
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Affiliation(s)
- Nadine Kämmer
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 504, Heidelberg D-69210, Germany.
| | - Lothar Erdinger
- Department of Medical Microbiology and Hygiene, Im Neuenheimer Feld 324, Heidelberg D-69120, Germany
| | - Thomas Braunbeck
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 504, Heidelberg D-69210, Germany.
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Xu XN, Chen SL, Jiang ZX, Nissa MU, Zou SM. Gill remodeling increases the respiratory surface area of grass carp (Ctenopharyngodon idella) under hypoxic stress. Comp Biochem Physiol A Mol Integr Physiol 2022; 272:111278. [PMID: 35872080 DOI: 10.1016/j.cbpa.2022.111278] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 07/19/2022] [Accepted: 07/19/2022] [Indexed: 11/29/2022]
Abstract
Seasonal changes, diurnal variations, and eutrophication result in periodic hypoxia in fish habitats, thus affecting the success of commercial aquaculture. In this study, the grass carp (Ctenopharyngodon idella) presented moderate hypoxia tolerance; they showed a medium critical oxygen tension during the loss of equilibrium. In response to 7 d of hypoxic exposure, the erythrocyte count and hemoglobin (Hb) concentration significantly increased (p < 0.01). To cope with the hypoxic environment, the grass carp underwent gill remodeling marked by reduction in the interlamellar cell mass (ILCM) and an increase in respiratory surface area. The gill remodeling under hypoxia was enabled by apoptosis induction. Although apoptotic signals were not found on ILCM cells, transferase dUTP nick end labeling (TUNEL) assay results indicated that after 1 d of hypoxic exposure, the number of TUNEL-positive cells per lamella increased until 4 d and then began to decrease. Consistent with the results of the TUNEL assay, the mRNA expression of apoptosis-related genes, caspase-3, Bax, and Bcl-2, increased at 1, 4, and 7 d of the hypoxia treatment. In addition, gill remodeling significantly (p < 0.01) decreased the concentration of sodium and chloride ions in the fish serum. These findings provide evidence that grass carps increase their respiratory surface area through gill remodeling by apoptosis in the gill filaments to acclimate to a hypoxic environment. This study expands our understanding of the morphological and physiological changes in grass carp in response to a hypoxic environment; therefore, it could be useful for maintaining grass carp production.
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Affiliation(s)
- Xiao-Na Xu
- Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China; Fisheries Research Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, China
| | - Song-Lin Chen
- Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Zhu-Xiang Jiang
- Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Meher Un Nissa
- Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Shu-Ming Zou
- Genetics and Breeding Center for Blunt Snout Bream, Ministry of Agriculture, Shanghai 201306, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China.
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Montero-Taboada R, Sotil G, Dionicio-Acedo J, Rosado-Salazar M, Aguirre-Velarde A. Tolerance of juvenile Peruvian rock seabass (Paralabrax humeralis Valenciennes, 1828) and Peruvian grunt (Anisotremus scapularis Tschudi, 1846) to low-oxygen conditions. JOURNAL OF FISH BIOLOGY 2022; 100:1497-1509. [PMID: 35398900 DOI: 10.1111/jfb.15060] [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: 11/17/2021] [Revised: 03/28/2022] [Accepted: 04/06/2022] [Indexed: 06/14/2023]
Abstract
Hypoxia is currently one of the greatest threats to coastal ecosystems worldwide, generating massive mortality of marine organisms, loss of benthic ecosystems and a decrease in fishery production. We evaluated and compared the tolerance to hypoxia of two species from different habitats of the Peruvian coast, the Peruvian rock seabass Paralabrax humeralis and the Peruvian grunt Anisotremus scapularis. The effect of hypoxia was measured as a function of the exposure time (progressive and chronic) on the behavioural and physiological responses of the two species, as well as on the enzymatic activity associated with the oxidative stress response of lactate dehydrogenase (LDH), superoxide dismutase (SOD) and alkaline phosphatase (AKP). The ventilatory frequency was measured at two different temperatures (16 and 22°C) under progressive hypoxia conditions to determine the ventilatory critical point (Vcp). A. scapularis showed a higher Vcp than P. humeralis, which was positively affected by temperature. The median lethal time of A. scapularis was 36 min at 60% of oxygen saturation, while P. humeralis showed no mortality after 31 days of exposure at 5% oxygen saturation. Different enzymatic activity (P < 0.05) between species under hypoxia was recorded, in SOD (gill and muscle) and AKP (blood). A general tendency, under hypoxia, to slightly increase LDH activity (except for blood in A. scapularis, P < 0.05) and SOD activity (mainly in muscle of A. scapularis, P < 0.05), and decrease AKP activity (mainly in liver of P. humeralis, P < 0.05) was observed. The response of P. humeralis to hypoxia goes through a reduction in activity and metabolism, so this species can be considered hypoxia-tolerant, allowing it to face hypoxia events during prolonged periods. On the other hand, A. scapularis response to hypoxia prioritizes avoidance mechanisms and, together with other adaptations, makes it especially vulnerable to hypoxia and able to be considered hypoxia-intolerant.
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Affiliation(s)
- Rebeca Montero-Taboada
- Universidad Científica del Sur, Carretera Panamerica Sur Km 19, Lima, Peru
- Instituto del Mar del Perú, Esquina General Valle y Gamarra S/N, Callao, Peru
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Giovanna Sotil
- Instituto del Mar del Perú, Esquina General Valle y Gamarra S/N, Callao, Peru
- Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Av. Venezuela s/n, Ciudad Universitaria, Lima, Peru
| | - Jhon Dionicio-Acedo
- Instituto del Mar del Perú, Esquina General Valle y Gamarra S/N, Callao, Peru
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van der Weele CM, Jeffery WR. Cavefish cope with environmental hypoxia by developing more erythrocytes and overexpression of hypoxia-inducible genes. eLife 2022; 11:69109. [PMID: 34984980 PMCID: PMC8765751 DOI: 10.7554/elife.69109] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 12/31/2021] [Indexed: 12/24/2022] Open
Abstract
Dark caves lacking primary productivity can expose subterranean animals to hypoxia. We used the surface-dwelling (surface fish) and cave-dwelling (cavefish) morphs of Astyanax mexicanus as a model for understanding the mechanisms of hypoxia tolerance in the cave environment. Primitive hematopoiesis, which is restricted to the posterior lateral mesoderm in other teleosts, also occurs in the anterior lateral mesoderm in Astyanax, potentially pre-adapting surface fish for hypoxic cave colonization. Cavefish have enlarged both hematopoietic domains and develop more erythrocytes than surface fish, which are required for normal development in both morphs. Laboratory-induced hypoxia suppresses growth in surface fish but not in cavefish. Both morphs respond to hypoxia by overexpressing hypoxia-inducible factor 1 (hif1) pathway genes, and some hif1 genes are constitutively upregulated in normoxic cavefish to similar levels as in hypoxic surface fish. We conclude that cavefish cope with hypoxia by increasing erythrocyte development and constitutive hif1 gene overexpression.
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Affiliation(s)
| | - William R Jeffery
- Department of Biology, University of Maryland, College Park, United States
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9
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Esmaeili M. Blood Performance: A New Formula for Fish Growth and Health. BIOLOGY 2021; 10:biology10121236. [PMID: 34943151 PMCID: PMC8698978 DOI: 10.3390/biology10121236] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/28/2022]
Abstract
Simple Summary The use of haematological and blood biochemistry parameters has proven to be effective and repeatable ways to monitor fish health. Testing these parameters is becoming more common in aquaculture studies. Further, it is widely accepted that fish with better health status are more likely to grow faster as less energy should be consumed for non-growth purposes. Here, a new formula (Blood Performance) is introduced, which contains five common haematological and blood biochemistry parameters: red blood cells, white blood cells, haemoglobin, haematocrit, and total protein. The idea behind this formula is that any single component of this formula cannot be reliable enough as a biomarker of fish health and growth. However, interestingly, Blood Performance can be much more reliable and accurate for monitoring fish health and growth. Abstract Monitoring fish health in a repeatable and accurate manner can contribute to the profitability and sustainability of aquaculture. Haematological and blood biochemistry parameters have been powerful tools and becoming increasingly common in aquaculture studies. Fish growth is closely related to its health status. A fish with a higher growth rate is more likely to be a healthy one. Any change in the physiological status of the fish, from pollution to nutritional stress, can cause changes in the blood parameters. Various aquaculture studies have measured the following components: red blood cells, white blood cells, haemoglobin, haematocrit, and total protein. However, because these parameters do not always follow the same trend across experimental fish, it is difficult to draw a firm conclusion about which parameter should be considered. Therefore, Blood Performance (BP) as a new formula is introduced, which is a more reliable indicator. This formula is simple and sums up the natural logarithm of the five above-mentioned parameters. More than 90 published peer-reviewed articles that measured these five parameters in the last six years confirmed the reliability and validity of this formula. Regardless of which supplements were added to the diets, the fish with a higher growth rate had higher BP as well. In addition, in 44 studies out of 53 articles, there was a significant positive correlation between specific growth rate and BP. Under different stressful situations, from pollution to thermal stress, the fish under stress had a lower BP than the control. Fish meal and fish oil replacement studies were further evidence for this formula and showed that adding excessive alternative proteins decreased growth along with BP. In conclusion, BP can be a reliable indicator of fish health and growth when it is compared between groups in the same experiment or farm. Although there was a positive correlation between specific growth rate and BP, comparing BP between experiments is not recommended. Standardising the haematological assays can improve the reliability and accuracy of BP across experiments.
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Affiliation(s)
- Moha Esmaeili
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart Private Bag 49, 15-21 Nubeena Cres, Taroona, TAS 7053, Australia
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10
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Borowiec BG, Scott GR. Rapid and reversible modulation of blood haemoglobin content during diel cycles of hypoxia in killifish (Fundulus heteroclitus). Comp Biochem Physiol A Mol Integr Physiol 2021; 261:111054. [PMID: 34384878 DOI: 10.1016/j.cbpa.2021.111054] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/04/2021] [Accepted: 08/04/2021] [Indexed: 11/16/2022]
Abstract
We investigated whether fish can make dynamic haematological adjustments to support aerobic metabolism during repeated cycles of hypoxia-reoxygenation. Killifish were acclimated to normoxia, constant hypoxia (2 kPa O2), or intermittent cycles of nocturnal hypoxia (12 h of normoxia: 12 h of 2 kPa O2 hypoxia) for 28 days. Normoxia-acclimated fish were sampled in the daytime in normoxia and after exposure to a single bout of nocturnal hypoxia. Each hypoxia acclimation group were sampled at the PO2 experienced during acclimation during both the day and night. All acclimation groups had increased blood haemoglobin content and haematocrit and reduced spleen mass during nocturnal hypoxia compared to normoxic controls. Blood haemoglobin content was negatively correlated with spleen mass at both the individual and group level. Fish acclimated to intermittent hypoxia rapidly reversed these changes during diurnal reoxygenation. The concentrations of haemoglobin, ATP, and GTP within erythrocytes did not vary substantially between groups. We also measured resting O2 consumption rate (MO2) and maximum MO2 (induced by an exhaustive chase) in hypoxia in each acclimation group. Fish acclimated to intermittent hypoxia maintained higher resting MO2 than other groups in hypoxia, comparable to the resting MO2 of normoxia-acclimated controls measured in normoxia. Differences in resting MO2 in hypoxia did not result from variation in O2 transport capacity, because maximal MO2 in hypoxia always exceeded resting MO2. Therefore, reversible modulation of blood haemoglobin content along with metabolic adjustments help killifish cope with intermittent cycles of hypoxia in the estuarine environment.
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Affiliation(s)
| | - Graham R Scott
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
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11
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Lei Y, Yang L, Zhou Y, Wang C, Lv W, Li L, He S. Hb adaptation to hypoxia in high-altitude fishes: Fresh evidence from schizothoracinae fishes in the Qinghai-Tibetan Plateau. Int J Biol Macromol 2021; 185:471-484. [PMID: 34214574 DOI: 10.1016/j.ijbiomac.2021.06.186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/27/2021] [Indexed: 10/21/2022]
Abstract
Uncovering the genetic basis of hypoxic adaptation is one of the most active research areas in evolutionary biology. Among air-breathing vertebrates, modifications of hemoglobin (Hb) play a pivotal role in mediating an adaptive response to high-altitude hypoxia. However, the relative contributions in water-breathing organisms are still unclear. Here, we tested the Hb concentration of fish at different altitudes. All species showed species-specific Hb concentration, which has a non-positive correlation with altitude. Moreover, we investigated the expression of Hb genes by the RNA-seq and quantitative real-time PCR (qRT-PCR), and Hb composition by two-dimensional electrophoresis (2-DE). The results showed that the multiple Hb genes and isoforms are co-expressed in schizothoracinae fishes endemic to the Qinghai-Tibetan Plateau (QTP). Phylogenetic analyses of Hb genes indicated that the evolutionary relationships are not easily reconciled with the organismal phylogeny. Furthermore, evidence of positive selection was found in the Hb genes of schizothoracinae fishes through the selection pressure analysis. We demonstrated that positively selected sites likely facilitated the functional divergence of Hb isoforms. Taken together, this study indicated that the long-term maintenance of high Hb concentration may be a disadvantage for physiologically acclimating to high altitude hypoxia. Meanwhile, the genetically based modification of Hb-O2 affinity in schizothoracinae fishes might facilitate the evolutionary adaptation to Tibetan aqueous environments.
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Affiliation(s)
- Yi Lei
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liandong Yang
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Zhou
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cheng Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenqi Lv
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Li
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shunping He
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China.
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12
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Physiology: An Important Tool to Assess the Welfare of Aquatic Animals. BIOLOGY 2021; 10:biology10010061. [PMID: 33467525 PMCID: PMC7830356 DOI: 10.3390/biology10010061] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 12/19/2022]
Abstract
Simple Summary Ensuring a good quality of life for animals is a matter of concern. Welfare assessment has been quite well developed for many terrestrial species, but it is less well characterized for aquatic animals. Classic methodologies, such as behavioral observation, seem unable to improve the wellbeing of aquatic animals when used alone, mainly due to the large number of species and the difficulty to obtain comparative results among taxa. For this reason, it is necessary to identify more methodologies that may be common to the main aquatic taxa of interest to humans: Fish, cephalopods, and crustaceans. Here we present a physiological framework for these taxa as a proxy to evaluate aquatic animal welfare. Physiology is a useful tool in this regard, since animals maintain their homeostasis in a range of values determined for each parameter. Changes occur depending on the type and degree of stress to which animals are subjected. Therefore, understanding the physiology of stress can offer information that helps improve the welfare of aquatic animals. Abstract The assessment of welfare in aquatic animals is currently under debate, especially concerning those kept by humans. The classic concept of animal welfare includes three elements: The emotional state of the organism (including the absence of negative experiences), the possibility of expressing normal behaviors, and the proper functioning of the organism. While methods for evaluating their emotions (such as fear, pain, and anguish) are currently being developed for aquatic species and understanding the natural behavior of all aquatic taxa that interact with humans is a task that requires more time, the evaluation of internal responses in the organisms can be carried out using analytical tools. This review aims to show the potential of the physiology of crustaceans, cephalopods, elasmobranchs, teleosts, and dipnoans to serve as indicators of their wellbeing. Since the classical methods of assessing welfare are laborious and time-consuming by evaluation of fear, pain, and anguish, the assessment may be complemented by physiological approaches. This involves the study of stress responses, including the release of hormones and their effects. Therefore, physiology may be of help in improving animal welfare.
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Tunnah L, Robertson CE, Turko AJ, Wright PA. Acclimation to prolonged aquatic hypercarbia or air enhances hemoglobin‑oxygen affinity in an amphibious fish. Comp Biochem Physiol A Mol Integr Physiol 2020; 252:110848. [PMID: 33217558 DOI: 10.1016/j.cbpa.2020.110848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/12/2020] [Accepted: 11/12/2020] [Indexed: 10/23/2022]
Abstract
When the amphibious mangrove rivulus (Kryptolebias marmoratus) leaves water for extended periods, hemoglobin-O2 binding affinity increases. We tested the hypothesis that the change in affinity was a consequence of hemoglobin isoform switching driven by exposure to environments associated with increased internal CO2 levels. We exposed K. marmoratus to either water (control, pH 8.1), air, aquatic hypercarbia (5.1 kPa CO2, pH 6.6-6.8), or aquatic acid (isocarbic control, pH 6.6-6.8), for 7 days, and measured hemoglobin-O2 affinity spectrophotometrically. We found that mangrove rivulus compensated for elevated CO2 and aquatic acid exposure by shifting hemoglobin-O2 affinity back to aquatic (control) levels when measured at an ecologically-relevant high CO2 level that would be experienced in vivo. Using proteomics, we found that the hemoglobin subunits present in the blood did not change between treatments, but air and aquatic acid exposure altered the abundance of cathodic hemoglobin subunits. We therefore conclude that hemoglobin isoform switching is not a primary strategy used by mangrove rivulus to adjust P50 under these conditions. Abundances of other RBC proteins also differed between treatment groups relative to control fish (e.g. Rhesus protein type A, band 3 anion exchanger). Overall, our data indicate that both aquatic hypercarbia and aquatic acidosis create similar changes in hemoglobin-O2 affinity as air exposure. However, the protein-level consequences differ between these groups, indicating that the red blood cell response of mangrove rivulus can be modulated depending on the environmental cue received.
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Affiliation(s)
- Louise Tunnah
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
| | - Cayleih E Robertson
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada; Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
| | - Andy J Turko
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada; Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada; Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada
| | - Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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14
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de Lima TM, de Ramos B, de Souza Tavares M, Leidens D, Ayres BS, Maciel FE, Nery LEM. Emersion behavior of the semi-terrestrial crab Neohelice granulata during hypoxic conditions: Lactate as a trigger. Comp Biochem Physiol A Mol Integr Physiol 2020; 252:110835. [PMID: 33144155 DOI: 10.1016/j.cbpa.2020.110835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 10/24/2020] [Accepted: 10/27/2020] [Indexed: 11/26/2022]
Abstract
Climate changes affecting aquatic environments are increasing, and the resultant environmental challenges require animals to adopt alternative compensatory behavioral and physiological strategies. In particular, low levels of dissolved O2 are a regular problem for estuarine animals, leading to activation of a series of behavioral and physiological responses. This study on the semi-terrestrial crab Neohelice granulata examined patterns of emersion behavior under different levels of dissolved O2 availability and the role of lactate in this behavior. Emersion behavior was recorded for 4.5 h for crabs in water at four different levels of dissolved O2 (6, 3, 2, and 1 mg O2/L) and with free access to air. Oxygen consumption and hemolymphatic lactate levels were measured using the same experimental design. Emersion behavior was also recorded for 70 min in normoxic water after lactate or saline injections. Crabs increased their emersion behavior only in severe hypoxia (1 mg O2/L), and O2 consumption decreased under more severe hypoxic conditions. Despite the increase in emersion behavior, which leads to higher O2 availability, an increase in hemolymphatic lactate levels indicates that the animals still need to resort to anaerobic pathways to fulfill their metabolic demand. Furthermore, animals injected with lactate showed higher emersion behaviors than animals injected with a saline solution even in normoxia. These results suggest that the increase in hemolymphatic lactate can act directly or indirectly as a trigger for the increase in emersion behavior in the semi-terrestrial crab N. granulata.
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Affiliation(s)
- Tábata Martins de Lima
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil.
| | - Bruna de Ramos
- Programa de Pós-Graduação em Gerenciamento Costeiro, Instituto de Oceanografia, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
| | - Margarita de Souza Tavares
- Instituto de Oceanografia, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
| | - Danusa Leidens
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
| | - Bruna Soares Ayres
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
| | - Fábio Everton Maciel
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
| | - Luiz Eduardo Maia Nery
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, FURG, Av. Itália, Km 8, Rio Grande, RS 96201-300, Brazil
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15
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The gaseous gastrointestinal tract of a seawater teleost, the English sole (Parophrys vetulus). Comp Biochem Physiol A Mol Integr Physiol 2020; 247:110743. [PMID: 32531535 DOI: 10.1016/j.cbpa.2020.110743] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/04/2020] [Accepted: 06/05/2020] [Indexed: 02/07/2023]
Abstract
There has been considerable recent progress in understanding the respiratory physiology of the gastrointestinal tract (GIT) in teleosts, but the respiratory conditions inside the GIT remain largely unknown, particularly the luminal PCO2 and PO2 levels. The GIT of seawater teleosts is of special interest due to its additional function of water absorption linked to HCO3- secretion, a process that may raise luminal PCO2 levels. Direct measurements of GIT PCO2 and PO2 using micro-optodes in the English sole (Parophrys vetulus; anaesthetized, artificially ventilated, 10-12 °C) revealed extreme luminal gas levels. Luminal PCO2 was 14-17 mmHg in the stomach and intestinal segments of fasted sole, considerably higher than arterial blood levels of 5 mmHg. Moreover, feeding, which raised intestinal HCO3- concentration, also raised luminal PCO2 to 34-50 mmHg. All these values were higher than comparable measurements in freshwater teleosts, and also greater than environmental CO2 levels of concern in aquaculture or global change scenarios. The PCO2 values in subintestinal vein blood draining the GIT of fed fish (28 mmHg) suggested some degree of equilibration with high luminal PCO2, whereas subintestinal vein PO2 levels were relatively low (9 mmHg). All luminal sections of the GIT were virtually anoxic (PO2 ≤ 0.3 mmHg), in both fasted and fed animals, a novel finding in teleosts.
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16
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Storz JF, Natarajan C, Grouleff MK, Vandewege M, Hoffmann FG, You X, Venkatesh B, Fago A. Oxygenation properties of hemoglobin and the evolutionary origins of isoform multiplicity in an amphibious air-breathing fish, the blue-spotted mudskipper ( Boleophthalmus pectinirostris). ACTA ACUST UNITED AC 2020; 223:jeb.217307. [PMID: 31836650 DOI: 10.1242/jeb.217307] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 12/09/2019] [Indexed: 12/13/2022]
Abstract
Among the numerous lineages of teleost fish that have independently transitioned from obligate water breathing to facultative air breathing, evolved properties of hemoglobin (Hb)-O2 transport may have been shaped by the prevalence and severity of aquatic hypoxia (which influences the extent to which fish are compelled to switch to aerial respiration) as well as the anatomical design of air-breathing structures and the cardiovascular system. Here, we examined the structure and function of Hbs in an amphibious, facultative air-breathing fish, the blue-spotted mudskipper (Boleophthalmus pectinirostris). We also characterized the genomic organization of the globin gene clusters of the species and we integrated phylogenetic and comparative genomic analyses to unravel the duplicative history of the genes that encode the subunits of structurally distinct mudskipper Hb isoforms (isoHbs). The B. pectinirostris isoHbs exhibit high intrinsic O2 affinities, similar to those of hypoxia-tolerant, water-breathing teleosts, and remarkably large Bohr effects. Genomic analysis of conserved synteny revealed that the genes that encode the α-type subunits of the two main adult isoHbs are members of paralogous gene clusters that represent products of the teleost-specific whole-genome duplication. Experiments revealed no appreciable difference in the oxygenation properties of co-expressed isoHbs in spite of extensive amino acid divergence between the alternative α-chain subunit isoforms. It therefore appears that the ability to switch between aquatic and aerial respiration does not necessarily require a division of labor between functionally distinct isoHbs with specialized oxygenation properties.
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Affiliation(s)
- Jay F Storz
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | | | - Magnus K Grouleff
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Alle 3, Aarhus C 8000, Denmark
| | - Michael Vandewege
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA.,Institute for Genomics, Biocomputing, and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Federico G Hoffmann
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA.,Institute for Genomics, Biocomputing, and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Xinxin You
- Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI Academy of Marine Sciences, BGI-Marine, BGI, Shenzhen 518083, China
| | - Byrappa Venkatesh
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, 61 Biopolis Drive, Singapore 138673, Singapore.,Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Angela Fago
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Alle 3, Aarhus C 8000, Denmark
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17
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Schwieterman GD, Bouyoucos IA, Potgieter K, Simpfendorfer CA, Brill RW, Rummer JL. Analysing tropical elasmobranch blood samples in the field: blood stability during storage and validation of the HemoCue® haemoglobin analyser. CONSERVATION PHYSIOLOGY 2019; 7:coz081. [PMID: 31803471 PMCID: PMC6883209 DOI: 10.1093/conphys/coz081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/06/2019] [Accepted: 09/15/2019] [Indexed: 06/10/2023]
Abstract
Blood samples collected from wild-caught fishes can provide important information regarding the effects of capture (and thus post-release survival) as well as other stressors. Unfortunately, blood samples often cannot be analysed immediately upon sampling, and blood parameters (e.g. blood oxygen levels and acid-base parameters) are known to change with storage duration due to the metabolic activity of the red blood cells. We obtained blood samples from both untreated and stressed individuals of both blacktip reef shark (Carcharhinus melanopterus) and sicklefin lemon shark (Negaprion acutidens) to determine the effects of storage duration on blood pH, haematocrit and haemoglobin concentration ([Hb]). We found no significant effects after storage on ice for up to 180 minutes. Moreover, to validate the usability of a HemoCue haemoglobin analyser (a point-of-care device), we compared data from this device to [Hb] determined using the cyanomethaemoglobin method with blood samples from 10 individuals from each of the aforementioned species as well as epaulette shark (Hemiscyllium ocellatum). Values from the HemoCue consistently overestimated [Hb], and we therefore developed the necessary correction equations. The correction equations were not statistically different among the three elasmobranch species within the biologically relevant range but did differ from published corrections developed using blood from temperate teleost fishes. Although the HemoCue is useful in field situations, development of species-specific calibration equations may be necessary to ensure the reliability of inter-species comparisons of blood [Hb]. Together, these data should increase confidence in haematological stress indicators in elasmobranch fishes, measurements of which are critical for understanding the impact of anthropogenic stressors on these ecologically important species.
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Affiliation(s)
- Gail D Schwieterman
- Department of Fisheries Science, Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA 23062, USA
| | - Ian A Bouyoucos
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
- PSL Research University, EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 58 Avenue Paul Alduy, Perpignan Cedex 66860, France
| | - Kristy Potgieter
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Colin A Simpfendorfer
- Centre for Sustainable Tropical Fisheries and Aquaculture, College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Richard W Brill
- Department of Fisheries Science, Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA 23062, USA
| | - Jodie L Rummer
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
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18
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Daane JM, Giordano D, Coppola D, di Prisco G, Detrich HW, Verde C. Adaptations to environmental change: Globin superfamily evolution in Antarctic fishes. Mar Genomics 2019; 49:100724. [PMID: 31735579 DOI: 10.1016/j.margen.2019.100724] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 10/27/2019] [Accepted: 11/01/2019] [Indexed: 02/08/2023]
Abstract
The ancient origins and functional versatility of globins make them ideal subjects for studying physiological adaptation to environmental change. Our goals in this review are to describe the evolution of the vertebrate globin gene superfamily and to explore the structure/function relationships of hemoglobin, myoglobin, neuroglobin and cytoglobin in teleost fishes. We focus on the globins of Antarctic notothenioids, emphasizing their adaptive features as inferred from comparisons with human proteins. We dedicate this review to Guido di Prisco, our co-author, colleague, friend, and husband of C.V. Ever thoughtful, creative, and enthusiastic, Guido spearheaded study of the structure, function, and evolution of the hemoglobins of polar fishes - this review is testimony to his wide-ranging contributions. Throughout his career, Guido inspired younger scientists to embrace polar biological research, and he challenged researchers of all ages to explore evolutionary adaptation in the context of global climate change. Beyond his scientific contributions, we will miss his warmth, his culture, and his great intellect. Guido has left an outstanding legacy, one that will continue to inspire us and our research.
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Affiliation(s)
- Jacob M Daane
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - Daniela Giordano
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, 80131 Napoli, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - Daniela Coppola
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, 80131 Napoli, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - Guido di Prisco
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - H William Detrich
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, 80131 Napoli, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy.
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19
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Ultsch GR, Regan MD. The utility and determination of P crit in fishes. ACTA ACUST UNITED AC 2019; 222:222/22/jeb203646. [PMID: 31722971 DOI: 10.1242/jeb.203646] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The critical O2 tension (P crit) is the lowest P O2 at which an animal can maintain some benchmark rate of O2 uptake (Ṁ O2 ). This P O2 has long served as a comparator of hypoxia tolerance in fishes and aquatic invertebrates, but its usefulness in this role, particularly when applied to fishes, has recently been questioned. We believe that P crit remains a useful comparator of hypoxia tolerance provided it is determined using the proper methods and hypoxia tolerance is clearly defined. Here, we review the available methods for each of the three steps of P crit determination: (1) measuring the most appropriate benchmark Ṁ O2 state for P crit determination (Ṁ O2,std, the Ṁ O2 required to support standard metabolic rate); (2) reducing water P O2 ; and (3) calculating P crit from the Ṁ O2 versus P O2 curve. We make suggestions on best practices for each step and for how to report P crit results to maximize their comparative value. We also discuss the concept of hypoxia tolerance and how P crit relates to a fish's overall hypoxia tolerance. When appropriate methods are used, P crit provides useful comparative physiological and ecological information about the aerobic contributions to a fish's hypoxic survival. When paired with other hypoxia-related physiological measurements (e.g. lactate accumulation, calorimetry-based measurements of metabolic depression, loss-of-equilibrium experiments), P crit contributes to a comprehensive understanding of how a fish combines aerobic metabolism, anaerobic metabolism and metabolic depression in an overall strategy for hypoxia tolerance.
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Affiliation(s)
- Gordon R Ultsch
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Matthew D Regan
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
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20
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Montgomery DW, Simpson SD, Engelhard GH, Birchenough SNR, Wilson RW. Rising CO 2 enhances hypoxia tolerance in a marine fish. Sci Rep 2019; 9:15152. [PMID: 31641181 PMCID: PMC6805886 DOI: 10.1038/s41598-019-51572-4] [Citation(s) in RCA: 20] [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] [Received: 07/03/2019] [Accepted: 09/25/2019] [Indexed: 11/09/2022] Open
Abstract
Global environmental change is increasing hypoxia in aquatic ecosystems. During hypoxic events, bacterial respiration causes an increase in carbon dioxide (CO2) while oxygen (O2) declines. This is rarely accounted for when assessing hypoxia tolerances of aquatic organisms. We investigated the impact of environmentally realistic increases in CO2 on responses to hypoxia in European sea bass (Dicentrarchus labrax). We conducted a critical oxygen (O2crit) test, a common measure of hypoxia tolerance, using two treatments in which O2 levels were reduced with constant ambient CO2 levels (~530 µatm), or with reciprocal increases in CO2 (rising to ~2,500 µatm). We also assessed blood acid-base chemistry and haemoglobin-O2 binding affinity of sea bass in hypoxic conditions with ambient (~650 μatm) or raised CO2 (~1770 μatm) levels. Sea bass exhibited greater hypoxia tolerance (~20% reduced O2crit), associated with increased haemoglobin-O2 affinity (~32% fall in P50) of red blood cells, when exposed to reciprocal changes in O2 and CO2. This indicates that rising CO2 which accompanies environmental hypoxia facilitates increased O2 uptake by the blood in low O2 conditions, enhancing hypoxia tolerance. We recommend that when impacts of hypoxia on aquatic organisms are assessed, due consideration is given to associated environmental increases in CO2.
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Affiliation(s)
- Daniel W Montgomery
- Bioscience Department, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
| | - Stephen D Simpson
- Bioscience Department, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Georg H Engelhard
- Centre for Environment, Fisheries & Aquaculture Science (Cefas), Pakefield Road, Lowestoft, NR33 0HT, UK
- School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Silvana N R Birchenough
- Centre for Environment, Fisheries & Aquaculture Science (Cefas), Pakefield Road, Lowestoft, NR33 0HT, UK
| | - Rod W Wilson
- Bioscience Department, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
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21
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Sánchez-García MA, Zottoli SJ, Roberson LM. Hypoxia Has a Lasting Effect on Fast-Startle Behavior of the Tropical Fish Haemulon plumieri. THE BIOLOGICAL BULLETIN 2019; 237:48-62. [PMID: 31441698 DOI: 10.1086/704337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Anthropogenic activities and climate change have resulted in an increase of hypoxic conditions in nearshore ecosystems worldwide. Depending on the persistence of a hypoxic event, the survival of aquatic animals can be compromised. Temperate fish exposed to hypoxia display a reduction in the probability of eliciting startle responses thought to be important for escape from predation. Here we examine the effect of hypoxia on the probability of eliciting fast-startle responses (fast-starts) of a tropical fish, the white grunt (Haemulon plumieri), and whether hypoxia has a prolonged impact on behavior once the fish are returned to normoxic conditions. White grunts collected from the San Juan Bay Estuary in Puerto Rico were exposed to an oxygen concentration of 2.5 mg L-1 (40% dissolved oxygen). We found a significant reduction in auditory-evoked fast-starts that lasted for at least 24 hours after fish were returned to normoxic conditions. Accessibility to the neuronal networks that underlie startle responses was an important motivator for this study. Mauthner cells are identifiable neurons found in most fish and amphibians, and these cells are known to initiate fast-starts in teleost fishes. The assumption that most of the short-latency responses in this study are Mauthner cell initiated provided the impetus to characterize the white grunt Mauthner cell. The identification of the cell provides a first step in understanding how low oxygen levels may impact a single cell and its circuit and the behavior it initiates.
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Mendez-Sanchez JF, Burggren WW. Very high blood oxygen affinity and large Bohr shift differentiates the air-breathing siamese fighting fish (Betta splendens) from the closely related anabantoid the blue gourami (Trichopodus trichopterus). Comp Biochem Physiol A Mol Integr Physiol 2018; 229:45-51. [PMID: 30503628 DOI: 10.1016/j.cbpa.2018.11.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 11/19/2018] [Indexed: 02/08/2023]
Abstract
The Siamese fighting fish, Betta splendens, and the blue gourami, Trichopodus trichopterus, are two closely related air-breathing anabantoid fishes. B. splendens is a sedentary facultative air breather frequenting often hypoxic waters, while T. trichopterus is a more active obligatory air-breather inhabiting better oxygenated waters. Despite their close taxonomic relationship, previous studies have shown inter-specific differences in both physiological and morphological plasticity. Consequently, we hypothesized that B. splendens would have the higher blood oxygen affinity characteristics typical of more hypoxia-tolerant fishes. Whole blood oxygen equilibrium curves were determined at 27 °C and pHs of 7.62, 7.44 and 7.25. At a pH of 7.62, the blood O2 affinity (P50) of B. splendens was just 2.9 mmHg, while that of T. trichopterus was ~5 times higher at 14.7 mmHg. There were no significant differences in P50 between males and females in either species. The Bohr coefficient in B. splendens and T. trichopterus was -1.79 and - 0.83, respectively. B. splendens, unlike T. trichopterus, showed a large Root effect. Hills cooperatively coefficient, n, was ~2 in both species, indicating a significant binding cooperative between oxygen and hemoglobin. Collectively, these differences in blood O2 transport characteristics in these two closely related species are likely correlated with the differing habitats in which they breed and inhabit as adults, as well as different activity levels. Finally, the very high blood O2 affinity of B. splendens is not extraordinary among air-breathing fish, as revealed by a review of the literature of blood oxygen affinity in air-breathing fishes.
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Affiliation(s)
- J F Mendez-Sanchez
- Departamento de Biología, Universidad Autónoma del Estado de México, Mexico.
| | - W W Burggren
- Department of Biological Sciences, University of North Texas, Denton, TX, USA.
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23
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Pelster B, Egg M. Hypoxia-inducible transcription factors in fish: expression, function and interconnection with the circadian clock. J Exp Biol 2018; 221:221/13/jeb163709. [DOI: 10.1242/jeb.163709] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
ABSTRACT
The hypoxia-inducible transcription factors are key regulators for the physiological response to low oxygen availability. In vertebrates, typically three Hif-α isoforms, Hif-1α, Hif-2α and Hif-3α, are expressed, each of which, together with Hif-1β, may form a functional heterodimer under hypoxic conditions, controlling expression of hundreds of genes. A teleost-specific whole-genome duplication complicates the analysis of isoform-specific functions in fish, but recent studies suggest that the existence of paralogues of a specific isoform opens up the possibility for a subfunctionalization. In contrast to during development inside the uterus, fish eggs are freely accessible and studies analyzing Hif expression in fish embryos during development have revealed that Hif proteins are not only controlling the hypoxic response, but are also crucial for proper development and organ differentiation. Significant advances have been made in our knowledge about tissue-specific functions of Hif proteins, especially with respect to gill or gonadal tissue. The hypoxia signalling pathway is known to be tightly and mutually intertwined with the circadian clock in zebrafish and mammals. Recently, a mechanistic explanation for the hypoxia-induced dampening of the transcriptional clock was detected in zebrafish, including also metabolically induced alterations of cellular redox signalling. In turn, MAP kinase-mediated H2O2 signalling modulates the temporal expression of Hif-1α protein, similar to the redox regulation of the circadian clock itself. Once again, the zebrafish has emerged as an excellent model organism with which to explore these specific functional aspects of basic eukaryotic cell biology.
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Affiliation(s)
- Bernd Pelster
- Institute of Zoology, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
- Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Margit Egg
- Institute of Zoology, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
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Cheng CH, Liang HY, Luo SW, Wang AL, Ye CX. The protective effects of vitamin C on apoptosis, DNA damage and proteome of pufferfish (Takifugu obscurus) under low temperature stress. J Therm Biol 2017; 71:128-135. [PMID: 29301681 DOI: 10.1016/j.jtherbio.2017.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 10/21/2017] [Accepted: 11/12/2017] [Indexed: 11/28/2022]
Abstract
The aim of this study was to investigate the protective effects of vitamin C on apoptosis, DNA damage and proteome of pufferfish under low temperature stress. Six diets were formulated to contain 2.60, 48.90, 95.50, 189.83, 382.40, 779.53mg/kg vitamin C. After 8-week feeding trial, fish were exposed to low temperature challenge. The results showed that pufferfish receiving vitamin C diet exhibited a significant decrease in ROS production (48.9-189.83mg/kg vitamin C diet groups), cytoplasmic free-Ca2+ concentration (48.9-779.53mg/kg vitamin C diet groups), apoptotic cell ratio (95.5-779.53mg/kg vitamin C diet groups) and DNA damage (189.83-779.53mg/kg vitamin C diet groups) under low temperature stress in comparison with those of control. We also investigated the alteration in protein expression under low temperature stress by a comparative proteomic analysis. The results demonstrated that 24 protein spots showed significantly differential expression in the cold-stress-treated group compared with those of the control group, and 5 protein spots were successfully identified. Furthermore, comparative proteomic analysis revealed that vitamin C could increase expressed proteins related to energy metabolism, immune responses and cytoskeleton. These findings would be helpful to understand the protective effects of vitamin C against cold stress.
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Affiliation(s)
- Chang-Hong Cheng
- Key Laboratory of Aquatic Product Processing, Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510300, PR China
| | - Hai-Yan Liang
- Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China
| | - Sheng-Wei Luo
- Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China
| | - An-Li Wang
- Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
| | - Chao-Xia Ye
- Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
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25
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Mislan KAS, Deutsch CA, Brill RW, Dunne JP, Sarmiento JL. Projections of climate-driven changes in tuna vertical habitat based on species-specific differences in blood oxygen affinity. GLOBAL CHANGE BIOLOGY 2017; 23:4019-4028. [PMID: 28657206 DOI: 10.1111/gcb.13799] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 05/19/2017] [Indexed: 06/07/2023]
Abstract
Oxygen concentrations are hypothesized to decrease in many areas of the ocean as a result of anthropogenically driven climate change, resulting in habitat compression for pelagic animals. The oxygen partial pressure, pO2 , at which blood is 50% saturated (P50 ) is a measure of blood oxygen affinity and a gauge of the tolerance of animals for low ambient oxygen. Tuna species display a wide range of blood oxygen affinities (i.e., P50 values) and therefore may be differentially impacted by habitat compression as they make extensive vertical movements to forage on subdaily time scales. To project the effects of end-of-the-century climate change on tuna habitat, we calculate tuna P50 depths (i.e., the vertical position in the water column at which ambient pO2 is equal to species-specific blood P50 values) from 21st century Earth System Model (ESM) projections included in the fifth phase of the Climate Model Intercomparison Project (CMIP5). Overall, we project P50 depths to shoal, indicating likely habitat compression for tuna species due to climate change. Tunas that will be most impacted by shoaling are Pacific and southern bluefin tunas-habitat compression is projected for the entire geographic range of Pacific bluefin tuna and for the spawning region of southern bluefin tuna. Vertical shifts in P50 depths will potentially influence resource partitioning among Pacific bluefin, bigeye, yellowfin, and skipjack tunas in the northern subtropical and eastern tropical Pacific Ocean, the Arabian Sea, and the Bay of Bengal. By establishing linkages between tuna physiology and environmental conditions, we provide a mechanistic basis to project the effects of anthropogenic climate change on tuna habitats.
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Affiliation(s)
- K A S Mislan
- School of Oceanography, University of Washington, Seattle, WA, USA
- eScience Institute, University of Washington, Seattle, WA, USA
| | - Curtis A Deutsch
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Richard W Brill
- Department of Fisheries Science, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, VA, USA
- Behavioral Ecology Branch, James J. Howard Marine Sciences Laboratory, NOAA Northeast Fisheries Science Center, Highlands, NJ, USA
| | - John P Dunne
- NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
| | - Jorge L Sarmiento
- Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ, USA
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26
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Baalsrud HT, Voje KL, Tørresen OK, Solbakken MH, Matschiner M, Malmstrøm M, Hanel R, Salzburger W, Jakobsen KS, Jentoft S. Evolution of Hemoglobin Genes in Codfishes Influenced by Ocean Depth. Sci Rep 2017; 7:7956. [PMID: 28801564 PMCID: PMC5554263 DOI: 10.1038/s41598-017-08286-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 07/11/2017] [Indexed: 11/09/2022] Open
Abstract
Understanding the genetic basis of adaptation is one of the main enigmas of evolutionary biology. Among vertebrates, hemoglobin has been well documented as a key trait for adaptation to different environments. Here, we investigate the role of hemoglobins in adaptation to ocean depth in the diverse teleost order Gadiformes, with species distributed at a wide range of depths varying in temperature, hydrostatic pressure and oxygen levels. Using genomic data we characterized the full hemoglobin (Hb) gene repertoire for subset of species within this lineage. We discovered a correlation between expanded numbers of Hb genes and ocean depth, with the highest numbers in species occupying shallower, epipelagic regions. Moreover, we demonstrate that the Hb genes have functionally diverged through diversifying selection. Our results suggest that the more variable environment in shallower water has led to selection for a larger Hb gene repertoire and that Hbs have a key role in adaptive processes in marine environments.
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Affiliation(s)
- Helle Tessand Baalsrud
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Kjetil Lysne Voje
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Ole Kristian Tørresen
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Monica Hongrø Solbakken
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Michael Matschiner
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway.,Institute of Fisheries Ecology, Johann Heinrich von Thünen-Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Hamburg, Germany
| | - Martin Malmstrøm
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Reinhold Hanel
- Zoological Institute, University of Basel, Basel, Switzerland
| | - Walter Salzburger
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway.,Institute of Fisheries Ecology, Johann Heinrich von Thünen-Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Hamburg, Germany
| | - Kjetill S Jakobsen
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Sissel Jentoft
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway. .,Department of Natural Sciences, Centre for Coastal Research, University of Agder, Kristiansand, Norway.
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27
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Aboagye DL, Allen PJ. Effects of acute and chronic hypoxia on acid–base regulation, hematology, ion, and osmoregulation of juvenile American paddlefish. J Comp Physiol B 2017; 188:77-88. [DOI: 10.1007/s00360-017-1104-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 05/02/2017] [Accepted: 05/07/2017] [Indexed: 11/30/2022]
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28
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Storz JF. Gene Duplication and Evolutionary Innovations in Hemoglobin-Oxygen Transport. Physiology (Bethesda) 2017; 31:223-32. [PMID: 27053736 DOI: 10.1152/physiol.00060.2015] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
During vertebrate evolution, duplicated hemoglobin (Hb) genes diverged with respect to functional properties as well as the developmental timing of expression. For example, the subfamilies of genes that encode the different subunit chains of Hb are ontogenetically regulated such that functionally distinct Hb isoforms are expressed during different developmental stages. In some vertebrate taxa, functional differentiation between co-expressed Hb isoforms may also contribute to physiologically important divisions of labor.
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Affiliation(s)
- Jay F Storz
- School of Biological Sciences, University of Nebraska, Lincoln, Nebraska
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29
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Gallo ND, Levin LA. Fish Ecology and Evolution in the World's Oxygen Minimum Zones and Implications of Ocean Deoxygenation. ADVANCES IN MARINE BIOLOGY 2016; 74:117-198. [PMID: 27573051 DOI: 10.1016/bs.amb.2016.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Oxygen minimum zones (OMZs) and oxygen limited zones (OLZs) are important oceanographic features in the Pacific, Atlantic, and Indian Ocean, and are characterized by hypoxic conditions that are physiologically challenging for demersal fish. Thickness, depth of the upper boundary, minimum oxygen levels, local temperatures, and diurnal, seasonal, and interannual oxycline variability differ regionally, with the thickest and shallowest OMZs occurring in the subtropics and tropics. Although most fish are not hypoxia-tolerant, at least 77 demersal fish species from 16 orders have evolved physiological, behavioural, and morphological adaptations that allow them to live under the severely hypoxic, hypercapnic, and at times sulphidic conditions found in OMZs. Tolerance to OMZ conditions has evolved multiple times in multiple groups with no single fish family or genus exploiting all OMZs globally. Severely hypoxic conditions in OMZs lead to decreased demersal fish diversity, but fish density trends are variable and dependent on region-specific thresholds. Some OMZ-adapted fish species are more hypoxia-tolerant than most megafaunal invertebrates and are present even when most invertebrates are excluded. Expansions and contractions of OMZs in the past have affected fish evolution and diversity. Current patterns of ocean warming are leading to ocean deoxygenation, causing the expansion and shoaling of OMZs, which is expected to decrease demersal fish diversity and alter trophic pathways on affected margins. Habitat compression is expected for hypoxia-intolerant species, causing increased susceptibility to overfishing for fisheries species. Demersal fisheries are likely to be negatively impacted overall by the expansion of OMZs in a warming world.
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Affiliation(s)
- N D Gallo
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States.
| | - L A Levin
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States
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30
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Borowiec BG, Crans KD, Khajali F, Pranckevicius NA, Young A, Scott GR. Interspecific and environment-induced variation in hypoxia tolerance in sunfish. Comp Biochem Physiol A Mol Integr Physiol 2016; 198:59-71. [PMID: 27085372 DOI: 10.1016/j.cbpa.2016.04.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 04/01/2016] [Accepted: 04/09/2016] [Indexed: 11/18/2022]
Abstract
Hypoxia tolerance is a plastic trait, and can vary between species. We compared hypoxia tolerance (hypoxic loss of equilibrium, LOE, and critical O2 tension, Pcrit) and traits that dictate O2 transport and metabolism in pumpkinseed (Lepomis gibbosus), bluegill (L. macrochirus), and the naturally occurring hybrid in different acclimation environments (wild versus lab-acclimated fish) and at different temperatures. Wild fish generally had lower Pcrit and lower PO2 at LOE in progressive hypoxia than lab-acclimated fish, but time to LOE in sustained hypoxia (PO2 of 2kPa) did not vary between environments. Wild fish also had greater gill surface area and higher haematocrit, suggesting that increased O2 transport capacity underlies the environmental variation in Pcrit. Metabolic (lactate dehydrogenase, LDH; pyruvate kinase, PK; citrate synthase; cytochrome c oxidase) and antioxidant (catalase and superoxide dismutase) enzyme activities varied appreciably between environments. Wild fish had higher protein contents across tissues and higher activities of LDH in heart, PK in brain, and catalase in brain, liver, and skeletal muscle. Otherwise, wild fish had lower activities for most enzymes. Warming temperature from 15 to 25°C increased O2 consumption rate, Pcrit, PO2 at LOE, and haemoglobin-O2 affinity, and decreased time to LOE, but pumpkinseed had ≥2-fold longer time to LOE than bluegill and hybrids across this temperature range. This was associated with higher LDH activities in the heart and muscle, and lower or similar antioxidant enzyme activities in several tissues. However, the greater hypoxia tolerance of pumpkinseed collapsed at 28°C, demonstrating that the interactive effects of hypoxia and warming temperature can differ between species. Overall, distinct mechanisms appear to underpin interspecific and environment-induced variation in hypoxia tolerance in sunfish.
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Affiliation(s)
- Brittney G Borowiec
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada.
| | - Kyle D Crans
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada
| | - Fariborz Khajali
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada; Department of Animal Science, Shahrekord University, Shahrekord, Chahar Mahal Va Bakhtiari, Iran
| | - Nicole A Pranckevicius
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada
| | - Alexander Young
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada
| | - Graham R Scott
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada
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31
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Molecular, behavioral, and performance responses of juvenile largemouth bass acclimated to an elevated carbon dioxide environment. J Comp Physiol B 2016; 186:297-311. [PMID: 26758610 DOI: 10.1007/s00360-016-0958-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 12/22/2015] [Accepted: 01/01/2016] [Indexed: 12/16/2022]
Abstract
Aquatic hypercarbia, either naturally occurring or anthropogenically induced, can have extensive impacts on aquatic environments and resident organisms. While the impact of acute hypercarbia exposure on the behavior and physiology of fishes has been well studied, relatively little work has examined the physiological impact and acclimation capacity of fishes to chronic hypercarbia. To better understand the impacts of prolonged hypercarbia exposure, largemouth bass were held at ambient CO2 (13 mg L(-1)) and elevated CO2 (31 mg L(-1); ≈ 21,000 µatm) for 58 days. Following this acclimation period, fish were subjected to three separate, yet complementary, experiments: (1) acute hypercarbia challenge of 120 mg L(-1) CO2 for 1 h to quantify physiological and molecular responses; (2) hypercarbia avoidance challenge to compare CO2 agitation and avoidance responses; and (3) swim performance challenge to quantify burst swimming performance. Acclimation to 31 mg L(-1) CO2 resulted in a significant constitutive upregulation of c-fos expression in erythrocytes, combined with significant constitutive expression of hsp70 in both gill and erythrocytes, relative to controls. Largemouth bass acclimated to elevated CO2 also had a reduced glucose response (relative to controls) following an acute CO2 exposure, indicating a reduced stress response to CO2 stressors. In addition, largemouth bass acclimated to elevated CO2 conditions required 50 % higher CO2 concentrations to illicit agitation behaviors and displayed prolonged burst swimming abilities in high CO2 environments relative to controls. Together, results demonstrate that largemouth bass exposed to chronic hypercarbia may possess a physiological advantage during periods of elevated CO2 relative to naïve fish, which may permit increased performance in hypercarbia.
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32
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Soldatov AA, Andreeva AY, Novitskaya VN, Parfenova IA. Coupling of membrane and metabolic functions in nucleated erythrocytes of Scorpaena porcus L. Under hypoxia in vivo and in vitro. J EVOL BIOCHEM PHYS+ 2014. [DOI: 10.1134/s0022093014050056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Turko AJ, Robertson CE, Bianchini K, Freeman M, Wright PA. The amphibious fish Kryptolebias marmoratus uses different strategies to maintain oxygen delivery during aquatic hypoxia and air exposure. ACTA ACUST UNITED AC 2014; 217:3988-95. [PMID: 25267849 DOI: 10.1242/jeb.110601] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Despite the abundance of oxygen in atmospheric air relative to water, the initial loss of respiratory surface area and accumulation of carbon dioxide in the blood of amphibious fishes during emersion may result in hypoxemia. Given that the ability to respond to low oxygen conditions predates the vertebrate invasion of land, we hypothesized that amphibious fishes maintain O2 uptake and transport while emersed by mounting a co-opted hypoxia response. We acclimated the amphibious fish Kryptolebias marmoratus, which are able to remain active for weeks in both air and water, for 7 days to normoxic brackish water (15‰, ~21kPa O2; control), aquatic hypoxia (~3.6kPa), normoxic air (~21 kPa) or aerial hypoxia (~13.6kPa). Angiogenesis in the skin and bucco-opercular chamber was pronounced in air- versus water-acclimated fish, but not in response to hypoxia. Aquatic hypoxia increased the O2-carrying capacity of blood via a large (40%) increase in red blood cell density and a small increase in the affinity of hemoglobin for O2 (P50 decreased 11%). In contrast, air exposure increased the hemoglobin O2 affinity (decreased P50) by 25% without affecting the number of red blood cells. Acclimation to aerial hypoxia both increased the O2-carrying capacity and decreased the hemoglobin O2 affinity. These results suggest that O2 transport is regulated both by O2 availability and also, independently, by air exposure. The ability of the hematological system to respond to air exposure independent of O2 availability may allow extant amphibious fishes, and may also have allowed primitive tetrapods to cope with the complex challenges of aerial respiration during the invasion of land.
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Affiliation(s)
- Andy J Turko
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Cayleih E Robertson
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Kristin Bianchini
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Megan Freeman
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
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34
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Gaulke GL, Dennis CE, Wahl DH, Suski CD. Acclimation to a low oxygen environment alters the hematology of largemouth bass (Micropterus salmoides). FISH PHYSIOLOGY AND BIOCHEMISTRY 2014; 40:129-140. [PMID: 23852572 DOI: 10.1007/s10695-013-9830-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 07/05/2013] [Indexed: 06/02/2023]
Abstract
One of the most severe impacts of urbanization on aquatic systems is the increasing presence of low oxygen environments caused by anthropogenic sources of pollution. As urbanization increases nationally and globally, it is becoming exceedingly important to understand how hypoxia affects aquatic fauna, especially fish species. In an effort to better understand the impacts of prolonged hypoxia on fishes, largemouth bass were held at 3.0 and 9.0 mg L⁻¹ for 50 days, which has previously shown to be temporally sufficient to impart plastic phenotypic changes. Following the holding period, fish from each group were subjected to a low dissolved oxygen (DO) challenge of 2.0 mg L⁻¹ for 6 h, and their physiological and hematological parameters were compared with control fish held for 6 h with no change in DO. There were no differences in the physiological stress responses between the two holding groups; however, the low oxygen holding group had increased hemoglobin and hematocrit levels following the 6-h low oxygen challenge compared with the high oxygen group. These results suggest largemouth bass exposed to chronic low oxygen conditions, either naturally or anthropogenically, may possess a beneficial advantage of increased oxygen uptake capacity during periods of low oxygen.
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Affiliation(s)
- Greg L Gaulke
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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35
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Wright PA. Environmental physiology of the mangrove rivulus, Kryptolebias marmoratus, a cutaneously breathing fish that survives for weeks out of water. Integr Comp Biol 2012; 52:792-800. [PMID: 22693260 PMCID: PMC3501097 DOI: 10.1093/icb/ics091] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The mangrove rivulus (Kryptolebias marmoratus) is an excellent model species for understanding the physiological mechanisms that fish use in coping with extreme environmental conditions, particularly cutaneous exchange during prolonged exposure to air. Their ability to self-fertilize and produce highly homozygous lineages provides the potential for examining environmental influences on structures and related functions without the complications of genetic variation. Over the past 10 years or so, we have gained a broader understanding of the mechanisms K. marmoratus use to maintain homeostasis when out of water for days to weeks. Gaseous exchange occurs across the skin, as dramatic remodeling of the gill reduces its effective surface area for exchange. Ionoregulation and osmoregulation are maintained in air by exchanging Na(+), Cl(-), and H(2)O across skin that contains a rich population of ionocytes. Ammonia excretion occurs in part by cutaneous NH(3) volatilization facilitated by ammonia transporters on the surface of the epidermis. Finally, new evidence indicates that cutaneous angiogenesis occurs when K. marmoratus are emersed for a week, suggesting a higher rate of blood flow to surface vessels. Taken together, these and other findings demonstrate that the skin of K. marmoratus takes on all the major functions attributed to fish gills, allowing them to move between aquatic and terrestrial environments with ease. Future studies should focus on variation in response to environmental changes between homozygous lineages to identify the genetic underpinnings of physiological responses.
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Affiliation(s)
- Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1.
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36
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Cook DG, Iftikar FI, Baker DW, Hickey AJR, Herbert NA. Low-O₂ acclimation shifts the hypoxia avoidance behaviour of snapper (Pagrus auratus) with only subtle changes in aerobic and anaerobic function. ACTA ACUST UNITED AC 2012; 216:369-78. [PMID: 23038727 DOI: 10.1242/jeb.073023] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
It was hypothesised that chronic hypoxia acclimation (preconditioning) would alter the behavioural low-O(2) avoidance strategy of fish as a result of both aerobic and anaerobic physiological adaptations. Avoidance and physiological responses of juvenile snapper (Pagrus auratus) were therefore investigated following a 6 week period of moderate hypoxia exposure (10.2-12.1 kPa P(O(2)), 21 ± 1 °C) and compared with those of normoxic controls (P(O(2))=20-21 kPa, 21 ± 1 °C). The critical oxygen pressure (P(crit)) limit of both groups was unchanged at ~7 kPa, as were standard, routine and maximum metabolic rates. However, hypoxia-acclimated fish showed increased tolerances to hypoxia in behavioural choice chambers by avoiding lower P(O(2)) levels (3.3 ± 0.7 vs 5.3 ± 1.1 kPa) without displaying greater perturbations of lactate or glucose. This behavioural change was associated with unexpected physiological adjustments. For example, a decrease in blood O(2) carrying capacity was observed after hypoxia acclimation. Also unexpected was an increase in whole-blood P(50) following acclimation to low O(2), perhaps facilitating Hb-O(2) off-loading to tissues. In addition, cardiac mitochondria measured in situ using permeabilised fibres showed improved O(2) uptake efficiencies. The proportion of the anaerobic enzyme lactate dehydrogenase, at least relative to the aerobic marker enzyme citrate synthase, also increased in heart and skeletal red muscle, indicating enhanced anaerobic potential, or in situ lactate metabolism, in these tissues. Overall, these data suggest that a prioritization of O(2) delivery and O(2) utilisation over O(2) uptake during long-term hypoxia may convey a significant survival benefit to snapper in terms of behavioural low-O(2) tolerance.
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Affiliation(s)
- Denham G Cook
- Leigh Marine Laboratory, The University of Auckland, Leigh, Warkworth 0941, New Zealand
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Richards JG. Physiological, behavioral and biochemical adaptations of intertidal fishes to hypoxia. J Exp Biol 2011; 214:191-9. [DOI: 10.1242/jeb.047951] [Citation(s) in RCA: 207] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Summary
Hypoxia survival in fish requires a well-coordinated response to either secure more O2 from the hypoxic environment or to limit the metabolic consequences of an O2 restriction at the mitochondria. Although there is a considerable amount of information available on the physiological, behavioral, biochemical and molecular responses of fish to hypoxia, very little research has attempted to determine the adaptive value of these responses. This article will review current attempts to use the phylogenetically corrected comparative method to define physiological and behavioral adaptations to hypoxia in intertidal fish and further identify putatively adaptive biochemical traits that should be investigated in the future. In a group of marine fishes known as sculpins, from the family Cottidae, variation in hypoxia tolerance, measured as a critical O2 tension (Pcrit), is primarily explained by variation in mass-specific gill surface area, red blood cell hemoglobin–O2 binding affinity, and to a lesser extent variation in routine O2 consumption rate (). The most hypoxia-tolerant sculpins consistently show aquatic surface respiration (ASR) and aerial emergence behavior during hypoxia exposure, but no phylogenetically independent relationship has been found between the thresholds for initiating these behaviors and Pcrit. At O2 levels below Pcrit, hypoxia survival requires a rapid reorganization of cellular metabolism to suppress ATP consumption to match the limited capacity for O2-independent ATP production. Thus, it is reasonable to speculate that the degree of metabolic rate suppression and the quantity of stored fermentable fuel is strongly selected for in hypoxia-tolerant fishes; however, these assertions have not been tested in a phylogenetic comparative model.
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Affiliation(s)
- Jeffrey G. Richards
- Department of Zoology, The University of British Columbia, 6270 University Blvd, Vancouver, BC, V6T 1Z4, Canada
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Wells R, Dunphy B. Potential impact of metabolic acidosis on the fixed-acid Bohr effect in snapper (Pagrus auratus) following angling stress. Comp Biochem Physiol A Mol Integr Physiol 2009; 154:56-60. [DOI: 10.1016/j.cbpa.2009.04.625] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 04/29/2009] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
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