1
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Kefford BJ, Ghalambor CK, Dewenter B, Poff NL, Hughes J, Reich J, Thompson R. Acute, diel, and annual temperature variability and the thermal biology of ectotherms. GLOBAL CHANGE BIOLOGY 2022; 28:6872-6888. [PMID: 36177681 PMCID: PMC9828456 DOI: 10.1111/gcb.16453] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
Global warming is increasing mean temperatures and altering temperature variability at multiple temporal scales. To better understand the consequences of changes in thermal variability for ectotherms it is necessary to consider thermal variation at different time scales (i.e., acute, diel, and annual) and the responses of organisms within and across generations. Thermodynamics constrain acute responses to temperature, but within these constraints and over longer time periods, organisms have the scope to adaptively acclimate or evolve. Yet, hypotheses and predictions about responses to future warming tend not to explicitly consider the temporal scale at which temperature varies. Here, focusing on multicellular ectothermic animals, we argue that consideration of multiple processes and constraints associated with various timescales is necessary to better understand how altered thermal variability because of climate change will affect ectotherms.
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Affiliation(s)
- Ben J. Kefford
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
| | - Cameron K. Ghalambor
- Department of Biology and Graduate Degree Program in EcologyColorado State UniversityFort CollinsColoradoUSA
- Department of Biology, Centre for Biodiversity Dynamics (CBD)Norwegian University of Science and Technology (NTNU)TrondheimNorway
| | - Beatrice Dewenter
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
| | - N. LeRoy Poff
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
- Department of Biology and Graduate Degree Program in EcologyColorado State UniversityFort CollinsColoradoUSA
| | - Jane Hughes
- Australian Rivers InstituteGriffith UniversityNathanQueenslandAustralia
| | - Jollene Reich
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
| | - Ross Thompson
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
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2
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Wei N, Yu Y, Yang Y, Wang XL, Zhong ZJ, Chen XF, Yu YQ. Inhibitions and Down-Regulation of Motor Protein Eg5 Expression in Primary Sensory Neurons Reveal a Novel Therapeutic Target for Pathological Pain. Neurotherapeutics 2022; 19:1401-1413. [PMID: 35764763 PMCID: PMC9587155 DOI: 10.1007/s13311-022-01263-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2022] [Indexed: 10/17/2022] Open
Abstract
The motor protein Eg5, known as kif11 or kinesin-5, interacts with adjacent microtubules in the mitotic spindle and plays essential roles in cell division, yet the function of Eg5 in mature postmitotic neurons remains largely unknown. In this study, we investigated the contribution and molecular mechanism of Eg5 in pathological pain. Pharmacological inhibition of Eg5 and a specific shRNA-expressing viral vector reversed complete Freund's adjuvant (CFA)-induced pain and abrogated vanilloid receptor subtype 1 (VR1) expression in dorsal root ganglion (DRG) neurons. In the dorsal root, Eg5 inhibition promoted VR1 axonal transport and decreased VR1 expression. In the spinal cord, Eg5 inhibition suppressed VR1 expression in axon terminals and impaired synapse formation in superficial laminae I/II. Finally, we showed that Eg5 is necessary for PI3K/Akt signalling-mediated VR1 membrane trafficking and pathological pain. The present study provides compelling evidence of a noncanonical function of Eg5 in primary sensory neurons. These results suggest that Eg5 may be a potential therapeutic target for intractable pain.
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Affiliation(s)
- Na Wei
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Yang Yu
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Yan Yang
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Xiao-Liang Wang
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Zhen-Juan Zhong
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Xue-Feng Chen
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China
| | - Yao-Qing Yu
- Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, 569 Xinsi Road, Baqiao, Xi'an, 710038, China.
- Key Laboratory of Brain Stress and Behavior, People's Liberation Army, Xi'an, 710038, China.
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3
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Ismailov II, Scharping JB, Andreeva IE, Friedlander MJ. Antarctic teleosts with and without hemoglobin behaviorally mitigate deleterious effects of acute environmental warming. PLoS One 2021; 16:e0252359. [PMID: 34818342 PMCID: PMC8612528 DOI: 10.1371/journal.pone.0252359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/12/2021] [Indexed: 11/19/2022] Open
Abstract
Recent studies forecast that many ectothermic animals, especially aquatic stenotherms, may not be able to thrive or even survive predicted climate change. These projections, however, generally do not call much attention to the role of behavior, an essential thermoregulatory mechanism of many ectotherms. Here we characterize species-specific locomotor and respiratory responses to acute ambient warming in two highly stenothermic Antarctic Notothenioid fishes, one of which (Chaenocephalus aceratus) lacks hemoglobin and appears to be less tolerant to thermal stress as compared to the other (Notothenia coriiceps), which expresses hemoglobin. At the onset of ambient warming, both species perform distinct locomotor maneuvers that appear to include avoidance reactions. In response to unavoidable progressive hyperthermia, fishes demonstrate a range of species-specific maneuvers, all of which appear to provide some mitigation of the deleterious effects of obligatory thermoconformation and to compensate for increasing metabolic demand by enhancing the efficacy of branchial respiration. As temperature continues to rise, Chaenocephalus aceratus supplements these behaviors with intensive pectoral fin fanning which may facilitate cutaneous respiration through its scaleless integument, and Notothenia coriiceps manifests respiratory-locomotor coupling during repetitive startle-like maneuvers which may further augment gill ventilation. The latter behaviors, found only in Notothenia coriiceps, have highly stereotyped appearance resembling Fixed Action Pattern sequences. Altogether, this behavioral flexibility could contribute to the reduction of the detrimental effects of acute thermal stress within a limited thermal range. In an ecologically relevant setting, this may enable efficient thermoregulation of fishes by habitat selection, thus facilitating their resilience in persistent environmental change.
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Affiliation(s)
- Iskander I Ismailov
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, Virginia, United States of America
| | - Jordan B Scharping
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, United States of America
| | - Iraida E Andreeva
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, Virginia, United States of America
| | - Michael J Friedlander
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, Virginia, United States of America
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
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4
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O'Brien KM, Joyce W, Crockett EL, Axelsson M, Egginton S, Farrell AP. Resilience of cardiac performance in Antarctic notothenioid fishes in a warming climate. J Exp Biol 2021; 224:268390. [PMID: 34042975 DOI: 10.1242/jeb.220129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Warming in the region of the Western Antarctic Peninsula is occurring at an unprecedented rate, which may threaten the survival of Antarctic notothenioid fishes. Herein, we review studies characterizing thermal tolerance and cardiac performance in notothenioids - a group that includes both red-blooded species and the white-blooded, haemoglobinless icefishes - as well as the relevant biochemistry associated with cardiac failure during an acute temperature ramp. Because icefishes do not feed in captivity, making long-term acclimation studies unfeasible, we focus only on the responses of red-blooded notothenioids to warm acclimation. With acute warming, hearts of the white-blooded icefish Chaenocephalus aceratus display persistent arrhythmia at a lower temperature (8°C) compared with those of the red-blooded Notothenia coriiceps (14°C). When compared with the icefish, the enhanced cardiac performance of N. coriiceps during warming is associated with greater aerobic capacity, higher ATP levels, less oxidative damage and enhanced membrane integrity. Cardiac performance can be improved in N. coriiceps with warm acclimation to 5°C for 6-9 weeks, accompanied by an increase in the temperature at which cardiac failure occurs. Also, both cardiac mitochondrial and microsomal membranes are remodelled in response to warm acclimation in N. coriiceps, displaying homeoviscous adaptation. Overall, cardiac performance in N. coriiceps is malleable and resilient to warming, yet thermal tolerance and plasticity vary among different species of notothenioid fishes; disruptions to the Antarctic ecosystem driven by climate warming and other anthropogenic activities endanger the survival of notothenioids, warranting greater protection afforded by an expansion of marine protected areas.
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Affiliation(s)
- Kristin M O'Brien
- Institute of Arctic Biology , University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA
| | - William Joyce
- Department of Biology - Zoophysiology, Aarhus University, 8000 Aarhus C, Denmark
| | | | - Michael Axelsson
- Department of Biological and Environmental Sciences, University of Gothenburg, 40530 Gothenburg, Sweden
| | - Stuart Egginton
- School of Biomedical Sciences , University of Leeds, Leeds LS2 9JT, UK
| | - Anthony P Farrell
- Department of Zoology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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5
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Homeoviscous adaptation occurs with thermal acclimation in biological membranes from heart and gill, but not the brain, in the Antarctic fish Notothenia coriiceps. J Comp Physiol B 2021; 191:289-300. [PMID: 33479792 PMCID: PMC8895410 DOI: 10.1007/s00360-020-01339-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 12/10/2020] [Accepted: 12/30/2020] [Indexed: 02/08/2023]
Abstract
As temperatures continue to rise, adjustments to biological membranes will be key for maintenance of function. It is largely unknown to what extent Antarctic notothenioids possess the capacity to remodel their biological membranes in response to thermal change. In this study, physical and biochemical properties were examined in membranes prepared from gill epithelia (plasma membranes), cardiac ventricles (microsomes, mitochondria), and brains (synaptic membranes, myelin, mitochondria) from Notothenia coriiceps following acclimation to 5 °C (or held at ambient temperature, 0 °C) for a minimum of 6 weeks. Fluidity was measured between 0 and 30 °C in all membranes, and polar lipid compositions and cholesterol contents were analyzed in a subset of biological membranes from all tissues. Osmotic permeability was measured in gills at 0 and 4 °C. Gill plasma membranes, cardiac mitochondria, and cardiac microsomes displayed reduced fluidity following acclimation to 5 °C, indicating compensation for elevated temperature. In contrast, no fluidity changes with acclimation were observed in any of the membranes prepared from brain. In all membranes, adjustments to the relative abundances of major phospholipid classes, and to the extent of fatty acid unsaturation, were undetectable following thermal acclimation. However, alterations in cholesterol contents and acyl chain length, consistent with the changes in fluidity, were observed in membranes from gill and cardiac tissue. Water permeability was reduced with 5 °C acclimation in gills, indicating near-perfect homeostatic efficacy. Taken together, these results demonstrate a homeoviscous response in gill and cardiac membranes, and limited plasticity in membranes from the nervous system, in an Antarctic notothenioid.
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6
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Gutt J, Isla E, Xavier JC, Adams BJ, Ahn IY, Cheng CHC, Colesie C, Cummings VJ, di Prisco G, Griffiths H, Hawes I, Hogg I, McIntyre T, Meiners KM, Pearce DA, Peck L, Piepenburg D, Reisinger RR, Saba GK, Schloss IR, Signori CN, Smith CR, Vacchi M, Verde C, Wall DH. Antarctic ecosystems in transition - life between stresses and opportunities. Biol Rev Camb Philos Soc 2020; 96:798-821. [PMID: 33354897 DOI: 10.1111/brv.12679] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 12/23/2022]
Abstract
Important findings from the second decade of the 21st century on the impact of environmental change on biological processes in the Antarctic were synthesised by 26 international experts. Ten key messages emerged that have stakeholder-relevance and/or a high impact for the scientific community. They address (i) altered biogeochemical cycles, (ii) ocean acidification, (iii) climate change hotspots, (iv) unexpected dynamism in seabed-dwelling populations, (v) spatial range shifts, (vi) adaptation and thermal resilience, (vii) sea ice related biological fluctuations, (viii) pollution, (ix) endangered terrestrial endemism and (x) the discovery of unknown habitats. Most Antarctic biotas are exposed to multiple stresses and considered vulnerable to environmental change due to narrow tolerance ranges, rapid change, projected circumpolar impacts, low potential for timely genetic adaptation, and migration barriers. Important ecosystem functions, such as primary production and energy transfer between trophic levels, have already changed, and biodiversity patterns have shifted. A confidence assessment of the degree of 'scientific understanding' revealed an intermediate level for most of the more detailed sub-messages, indicating that process-oriented research has been successful in the past decade. Additional efforts are necessary, however, to achieve the level of robustness in scientific knowledge that is required to inform protection measures of the unique Antarctic terrestrial and marine ecosystems, and their contributions to global biodiversity and ecosystem services.
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Affiliation(s)
- Julian Gutt
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Columbusstr., Bremerhaven, 27568, Germany
| | - Enrique Isla
- Institute of Marine Sciences-CSIC, Passeig Maritim de la Barceloneta 37-49, Barcelona, 08003, Spain
| | - José C Xavier
- University of Coimbra, MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, Coimbra, Portugal.,British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 OET, U.K
| | - Byron J Adams
- Department of Biology and Monte L. Bean Museum, Brigham Young University, Provo, UT, U.S.A
| | - In-Young Ahn
- Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, South Korea
| | - C-H Christina Cheng
- Department of Evolution, Ecology and Behavior, University of Illinois, Urbana, IL, U.S.A
| | - Claudia Colesie
- School of GeoSciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh, EH9 3FF, U.K
| | - Vonda J Cummings
- National Institute of Water and Atmosphere Research Ltd (NIWA), 301 Evans Bay Parade, Greta Point, Wellington, New Zealand
| | - Guido di Prisco
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino 111, Naples, I-80131, Italy
| | - Huw Griffiths
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 OET, U.K
| | - Ian Hawes
- Coastal Marine Field Station, University of Waikato, 58 Cross Road, Tauranga, 3100, New Zealand
| | - Ian Hogg
- School of Science, University of Waikato, Private Bag 3105, Hamilton, 3240, New Zealand.,Canadian High Antarctic Research Station, Polar Knowledge Canada, PO Box 2150, Cambridge Bay, NU, X0B 0C0, Canada
| | - Trevor McIntyre
- Department of Life and Consumer Sciences, University of South Africa, Private Bag X6, Florida, 1710, South Africa
| | - Klaus M Meiners
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, and Australian Antarctic Program Partnership, University of Tasmania, 20 Castray Esplanade, Battery Point, TAS, 7004, Australia
| | - David A Pearce
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 OET, U.K.,Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University at Newcastle, Northumberland Road, Newcastle upon Tyne, NE1 8ST, U.K
| | - Lloyd Peck
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 OET, U.K
| | - Dieter Piepenburg
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Columbusstr., Bremerhaven, 27568, Germany
| | - Ryan R Reisinger
- Centre d'Etudes Biologique de Chizé, UMR 7372 du Centre National de la Recherche Scientifique - La Rochelle Université, Villiers-en-Bois, 79360, France
| | - Grace K Saba
- Center for Ocean Observing Leadership, Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Rd., New Brunswick, NJ, 08901, U.S.A
| | - Irene R Schloss
- Instituto Antártico Argentino, Buenos Aires, Argentina.,Centro Austral de Investigaciones Científicas, Bernardo Houssay 200, Ushuaia, Tierra del Fuego, CP V9410CAB, Argentina.,Universidad Nacional de Tierra del Fuego, Ushuaia, Tierra del Fuego, CP V9410CAB, Argentina
| | - Camila N Signori
- Oceanographic Institute, University of São Paulo, Praça do Oceanográfico, 191, São Paulo, CEP: 05508-900, Brazil
| | - Craig R Smith
- Department of Oceanography, University of Hawaii at Manoa, 1000 Pope Road, Honolulu, HI, 96822, U.S.A
| | - Marino Vacchi
- Institute for the Study of the Anthropic Impacts and the Sustainability of the Marine Environment (IAS), National Research Council of Italy (CNR), Via de Marini 6, Genoa, 16149, Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino 111, Naples, I-80131, Italy
| | - Diana H Wall
- Department of Biology and School of Global Environmental Sustainability, Colorado State University, Fort Collins, CO, U.S.A
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7
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Torson AS, Dong YW, Sinclair BJ. Help, there are ‘omics’ in my comparative physiology! J Exp Biol 2020; 223:223/24/jeb191262. [DOI: 10.1242/jeb.191262] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abstract
‘Omics’ methods, such as transcriptomics, proteomics, lipidomics or metabolomics, yield simultaneous measurements of many related molecules in a sample. These approaches have opened new opportunities to generate and test hypotheses about the mechanisms underlying biochemical and physiological phenotypes. In this Commentary, we discuss general approaches and considerations for successfully integrating omics into comparative physiology. The choice of omics approach will be guided by the availability of existing resources and the time scale of the process being studied. We discuss the use of whole-organism extracts (common in omics experiments on small invertebrates) because such an approach may mask underlying physiological mechanisms, and we consider the advantages and disadvantages of pooling samples within biological replicates. These methods can bring analytical challenges, so we describe the most easily analyzed omics experimental designs. We address the propensity of omics studies to digress into ‘fishing expeditions’ and show how omics can be used within the hypothetico-deductive framework. With this Commentary, we hope to provide a roadmap that will help newcomers approach omics in comparative physiology while avoiding some of the potential pitfalls, which include ambiguous experiments, long lists of candidate molecules and vague conclusions.
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Affiliation(s)
- Alex S. Torson
- Department of Biology, The University of Western Ontario, London, ON N6A 5B7, Canada
| | - Yun-wei Dong
- The Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao 266003, PR China
| | - Brent J. Sinclair
- Department of Biology, The University of Western Ontario, London, ON N6A 5B7, Canada
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8
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O'Brien KM, Rix AS, Grove TJ, Sarrimanolis J, Brooking A, Roberts M, Crockett EL. Characterization of the hypoxia-inducible factor-1 pathway in hearts of Antarctic notothenioid fishes. Comp Biochem Physiol B Biochem Mol Biol 2020; 250:110505. [PMID: 32966875 DOI: 10.1016/j.cbpb.2020.110505] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 09/09/2020] [Accepted: 09/14/2020] [Indexed: 02/06/2023]
Abstract
The ability of Antarctic notothenioid fishes to mount a robust molecular response to hypoxia is largely unknown. The transcription factor, hypoxia-inducible factor-1 (HIF-1), a heterodimer of HIF-1α and HIF-1β subunits, is the master regulator of oxygen homeostasis in most metazoans. We sought to determine if, in the hearts of Antarctic notothenioids, HIF-1 is activated and functional in response to either an acute heat stress or hypoxia. The red-blooded Notothenia coriiceps and the hemoglobinless icefish, Chaenocephalus aceratus, were exposed to their critical thermal maximum (CTMAX) or hypoxia (5.0 ± 0.3 mg of O2 L-1) for 2 h. Additionally, N. coriiceps was exposed to 2.3 ± 0.3 mg of O2 L-1 for 12 h, and red-blooded Gobionotothen gibberifrons was exposed to both levels of hypoxia. Levels of HIF-1α were quantified in nuclei isolated from heart ventricles using western blotting. Transcript levels of genes involved in anaerobic metabolism, and known to be regulated by HIF-1, were quantified by real-time PCR, and lactate levels were measured in heart ventricles. Protein levels of HIF-1α increase in nuclei of hearts of N. coriiceps and C. aceratus in response to exposure to CTMAX and in hearts of N. coriiceps exposed to severe hypoxia, yet mRNA levels of anaerobic metabolic genes do not increase in any species, nor do lactate levels increase, suggesting that HIF-1 does not stimulate metabolic remodeling in hearts of notothenioids under these conditions. Together, these data suggest that Antarctic notothenioids may be vulnerable to hypoxic events, which are likely to increase with climate warming.
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Affiliation(s)
- K M O'Brien
- Institute of Arctic Biology, Fairbanks, Alaska, United States of America.
| | - A S Rix
- Institute of Arctic Biology, Fairbanks, Alaska, United States of America
| | - T J Grove
- Department of Biology, Valdosta State University, Valdosta, GA 31698, United States of America
| | - J Sarrimanolis
- Institute of Arctic Biology, Fairbanks, Alaska, United States of America
| | - A Brooking
- Institute of Arctic Biology, Fairbanks, Alaska, United States of America
| | - M Roberts
- Institute of Arctic Biology, Fairbanks, Alaska, United States of America
| | - E L Crockett
- Department of Biological Sciences, Ohio University, Athens, OH 45701, United States of America
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9
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Wilson KA, Wang L, MacDermott-Opeskin H, O'Mara ML. The Fats of Life: Using Computational Chemistry to Characterise the Eukaryotic Cell Membrane. Aust J Chem 2020. [DOI: 10.1071/ch19353] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Our current knowledge of the structural dynamics and complexity of lipid bilayers is still developing. Computational techniques, especially molecular dynamics simulations, have increased our understanding significantly as they allow us to model functions that cannot currently be experimentally resolved. Here we review available computational tools and techniques, the role of the major lipid species, insights gained into lipid bilayer structure and function from molecular dynamics simulations, and recent progress towards the computational modelling of the physiological complexity of eukaryotic lipid bilayers.
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