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Luckenbach T, Burkhardt-Medicke K. Differing temperature dependencies of functional homologs zebrafish Abcb4 and human ABCB1. Front Pharmacol 2024; 15:1426040. [PMID: 39166110 PMCID: PMC11333832 DOI: 10.3389/fphar.2024.1426040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 07/16/2024] [Indexed: 08/22/2024] Open
Abstract
The ATP binding cassette (ABC) transporters human ABCB1 and zebrafish (Danio rerio) Abcb4 are functionally homologous multixenobiotic/multidrug (MXR/MDR) efflux transporters that confer the efflux of a broad range of diverse chemical compounds from the cell. As ATPases, the transporters utilize the energy released by ATP cleavage for protein conformation changes and concomitant active transport of substrate compounds. The temperatures, at which human ABCB1 and zebrafish Abcb4 need to function, can substantially differ: Whereas the ambient temperature of human ABCB1, which is that of the human body, is constant, zebrafish Abcb4 has to be active in a wider temperature range as the body temperature of zebrafish can considerably vary, depending on the ambient water temperature (18°C-40°C). Here, we examined the effect of temperature on the ATPase activities of recombinant human ABCB1 and zebrafish Abcb4 generated with the baculovirus expression system. Incubation temperatures for enzyme reactions were set to 37°C and 27°C, corresponding to the human body temperature and the cultivation temperature of zebrafish in our lab, respectively. For stimulation and inhibition of zebrafish Abcb4 and human ABCB1 ATPase activities verapamil and cyclosporin A were added at different concentrations and 50% effect concentrations (EC50) were determined. The different temperatures had a stronger effect on the human ABCB1 than on the zebrafish Abcb4 ATPase: Differences between EC50 values for verapamil at 37°C and 27°C, respectively, were 1.8-fold for human ABCB1 but only 1.2-fold for zebrafish Abcb4. Activation energies (Ea) of basal and verapamil-stimulated ATPases, calculated based on the Arrhenius equation, were 2-fold (basal) and 1.5-fold (verapamil-stimulated) higher for human ABCB1 than for zebrafish Abcb4. The differences between zebrafish Abcb4 and human ABCB1 ATPases in temperature sensitivity and activation energy could be important for the comparison of the functional properties of the two transporter proteins in the context of pharmaco-/toxicokinetics. Related to this, our finding that at equal reaction conditions the zebrafish Abcb4 ATPase activity tended to be generally higher than that of human ABCB1 may also be important, as this may point to a higher substrate compound transport rate of Abcb4.
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Affiliation(s)
- Till Luckenbach
- Department Ecotoxicology, Helmholtz Centre for Environmental Research—UFZ, Leipzig, Germany
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Meza-Buendia AK, Aparicio-Trejo OE, Díaz F, Pedraza-Chaverri J, Álvarez-Delgado C, Rosas C. Climate change consequences on the systemic heart of female Octopus maya: oxidative phosphorylation assessment and the antioxidant system. Biol Open 2024; 13:bio060103. [PMID: 38752595 PMCID: PMC11155352 DOI: 10.1242/bio.060103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 04/05/2024] [Indexed: 06/09/2024] Open
Abstract
There is evidence that indicates that temperature modulates the reproduction of the tropical species Octopus maya, through the over- or under-expression of many genes in the brain. If the oxygen supply to the brain depends on the circulatory system, how temperature affects different tissues will begin in the heart, responsible for pumping the oxygen to tissues. The present study examines the impact of heat stress on the mitochondrial function of the systemic heart of adult O. maya. The mitochondrial metabolism and antioxidant defense system were measured in the systemic heart tissue of female organisms acclimated to different temperatures (24, 26, and 30°C). The results show that acclimation temperature affects respiratory State 3 and State 4o (oligomycin-induced) with higher values observed in females acclimated at 26°C. The antioxidant defense system is also affected by acclimation temperature with significant differences observed in superoxide dismutase, glutathione S-transferase activities, and glutathione levels. The results suggest that high temperatures (30°C) could exert physical limitations on the circulatory system through the heart pumping, affecting nutrient and oxygen transport to other tissues, including the brain, which exerts control over the reproductive system. The role of the cardiovascular system in supporting aerobic metabolism in octopus females is discussed.
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Affiliation(s)
- Ana Karen Meza-Buendia
- Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada, 22860Ensenada, Baja California, México
| | - Omar Emiliano Aparicio-Trejo
- Departamento de Fisiopatología Cardio-Renal, Instituto Nacional de Cardiología “Ignacio Chávez”, 14080 Ciudad de México, México
| | - Fernando Díaz
- Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada, 22860Ensenada, Baja California, México
| | - José Pedraza-Chaverri
- Laboratorio F-315, Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, 04510, Ciudad de México, México
| | - Carolina Álvarez-Delgado
- Departamento de Innovación Biomédica, Centro de Investigación Científica y de Educación Superior de Ensenada, 22860 Ensenada, Baja California, México
| | - Carlos Rosas
- Laboratorio de Ecofisiología Aplicada, Unidad Multidisciplinaria de Docencia e Investigación, de Sisal, Facultad de Ciencias, Universidad Nacional Autónoma de México, 97356 Puerto de Abrigo, Sisal, Yucatán, México
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Zillig KW, Hannan KD, Baird SE, Cocherell DE, Poletto JB, Fangue NA. Effects of acclimation temperature and feed restriction on the metabolic performance of green sturgeon. CONSERVATION PHYSIOLOGY 2024; 12:coae021. [PMID: 38784525 PMCID: PMC11113080 DOI: 10.1093/conphys/coae021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 03/05/2024] [Accepted: 03/31/2024] [Indexed: 05/25/2024]
Abstract
Green sturgeon (Acipenser medirostris) are an anadromous threatened species of sturgeon found along the Pacific coast of North America. The southern distinct population segment only spawns in the Sacramento River and is exposed to water temperatures kept artificially cold for the conservation and management of winter-run Chinook salmon (Oncorhynchus tshawytscha). Past research has demonstrated costs of cold-water rearing including reduced growth rates, condition and survivorship of juvenile green sturgeon. Our research investigates how the stressors of water temperature and food limitation influence the metabolic performance of green sturgeon. We reared green sturgeon at two acclimation temperatures (13 and 19°C) and two ration amounts (100% and 40% of optimal feed). We then measured the routine and maximum metabolic rates (RMR and MMR, respectively) of sturgeon acclimated to these rearing conditions across a range of acute temperature exposures (11 to 31°C). Among both temperature acclimation treatments (13 or 19°C), we found that feed restriction reduced RMR across a range of acute temperatures. The influence of feed restriction on RMR and MMR interacted with acclimation temperature. Fish reared at 13°C preserved their MMR and aerobic scope (AS) despite feed restriction, while fish fed reduced rations and acclimated to 19°C showed reduced MMR and AS capacity primarily at temperatures below 16°C. The sympatry of threatened green sturgeon with endangered salmonids produces a conservation conflict, such that cold-water releases for the conservation of at-risk salmonids may constrain the metabolic performance of juvenile green sturgeon. Understanding the impacts of environmental conditions (e.g. temperature, dissolved oxygen) on ecological interactions of green sturgeon will be necessary to determine the influence of salmonid-focused management.
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Affiliation(s)
- Kenneth W Zillig
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
| | - Kelly D Hannan
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
| | - Sarah E Baird
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
| | - Dennis E Cocherell
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
| | - Jamilynn B Poletto
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
| | - Nann A Fangue
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616-5270, USA
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Ruth A, Svendsen MBS, Nygaard R, Christensen EAF, Bushnell PG, Steffensen JF. Physiological effects of temperature on Greenland halibut Reinhardtius hippoglossoides shows high vulnerability of Arctic stenotherms to global warming. JOURNAL OF FISH BIOLOGY 2023; 103:675-683. [PMID: 37170416 DOI: 10.1111/jfb.15434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
Global warming affects the metabolism of ectothermic aquatic breathers forcing them to migrate and undergo high-latitudinal distribution shifts to circumvent the temperature-induced mismatch between increased metabolic demand and reduced water oxygen availability. Here the authors examined the effects of temperature on oxygen consumption rates in an Arctic stenotherm, the Greenland halibut Reinhardtius hippoglossoides, and calculated the optimal temperature for maximum aerobic scope, AS(Topt,AS ), which was found to be 2.44°C. They also investigated cardiac performance as limiting the oxygen transport chain at high temperatures by measuring maximum heart rate (fHmax ) over acute temperature increases and found various metrics related to fHmax to be at least 3.2°C higher than Topt,AS . The authors' measured Topt,AS closely reflected in situ temperature occurrences of Greenland halibut from long-term tagging studies, showing that AS of the species is adapted to its habitat temperature, and is thus a good proxy for the species' sensitivity to environmental warming. The authors did not find a close connection between fHmax and Topt,AS , suggesting that cardiac performance is not limiting for the oxygen transport chain at high temperatures in this particular Arctic stenotherm. The authors' estimate of the thermal envelope for AS of Greenland halibut was from -1.89 to 8.07°C, which is exceptionally narrow compared to most other species of fish. As ocean temperatures increase most rapidly in the Arctic in response to climate change, and species in these areas have limited possibility for further poleward-range shifts, these results suggest potential severe effects of global warming on Arctic stenotherms, such as the Greenland halibut. The considerable economic importance of the species raises concerns for future fisheries and species conservation of Arctic stenotherms in the Northern Hemisphere.
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Affiliation(s)
- Andreas Ruth
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | | | - Rasmus Nygaard
- Department of Fish and Shellfish, Greenland Institute of Natural Resources, Nuuk, Greenland
| | | | - Peter G Bushnell
- Department of Biological Sciences, Indiana University South Bend, South Bend, Indiana, USA
| | - John Fleng Steffensen
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
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McInturf AG, Zillig KW, Cook K, Fukumoto J, Jones A, Patterson E, Cocherell DE, Michel CJ, Caillaud D, Fangue NA. In hot water? Assessing the link between fundamental thermal physiology and predation of juvenile Chinook salmon. Ecosphere 2022. [DOI: 10.1002/ecs2.4264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Alexandra G. McInturf
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
- Animal Behavior Graduate Group University of California Davis California USA
- Coastal Oregon Marine Experiment Station Oregon State University Newport Oregon USA
| | - Ken W. Zillig
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
- Graduate Group in Ecology University of California Davis California USA
| | - Katherine Cook
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
| | - Jacqueline Fukumoto
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
| | - Anna Jones
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
| | - Emily Patterson
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
| | - Dennis E. Cocherell
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
| | - Cyril J. Michel
- NOAA Southwest Fisheries Science Center, Fisheries Ecology Division Santa Cruz California USA
| | - Damien Caillaud
- Department of Anthropology University of California Davis California USA
| | - Nann A. Fangue
- Department of Wildlife, Fish and Conservation Biology University of California Davis California USA
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Blessing EM, Parekh A, Betensky RA, Babb J, Saba N, Debure L, Varga AW, Ayappa I, Rapoport DM, Butler TA, de Leon MJ, Wisniewski T, Lopresti BJ, Osorio RS. Association between lower body temperature and increased tau pathology in cognitively normal older adults. Neurobiol Dis 2022; 171:105748. [PMID: 35550158 PMCID: PMC9751849 DOI: 10.1016/j.nbd.2022.105748] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/25/2022] [Accepted: 05/05/2022] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND Preclinical studies suggest body temperature (Tb) and consequently brain temperature has the potential to bidirectionally interact with tau pathology in Alzheimer's Disease (AD). Tau phosphorylation is substantially increased by a small (<1 °C) decrease in temperature within the human physiological range, and thermoregulatory nuclei are affected by tau pathology early in the AD continuum. In this study we evaluated whether Tb (as a proxy for brain temperature) is cross-sectionally associated with clinically utilized markers of tau pathology in cognitively normal older adults. METHODS Tb was continuously measured with ingestible telemetry sensors for 48 h. This period included two nights of nocturnal polysomnography to delineate whether Tb during waking vs sleep is differentially associated with tau pathology. Tau phosphorylation was assessed with plasma and cerebrospinal fluid (CSF) tau phosphorylated at threonine 181 (P-tau), sampled the day following Tb measurement. In addition, neurofibrillary tangle (NFT) burden in early Braak stage regions was imaged with PET-MR using the [18F]MK-6240 radiotracer on average one month later. RESULTS Lower Tb was associated with increased NFT burden, as well as increased plasma and CSF P-tau levels (p < 0.05). NFT burden was associated with lower Tb during waking (p < 0.05) but not during sleep intervals. Plasma and CSF P-tau levels were highly correlated with each other (p < 0.05), and both variables were correlated with tau tangle radiotracer uptake (p < 0.05). CONCLUSIONS These results, the first available for human, suggest that lower Tb in older adults may be associated with increased tau pathology. Our findings add to the substantial preclinical literature associating lower body and brain temperature with tau hyperphosphorylation. CLINICAL TRIAL NUMBER NCT03053908.
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Affiliation(s)
- Esther M Blessing
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
| | - Ankit Parekh
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, United States of America.
| | - Rebecca A Betensky
- Department of NYU School of Global Public Health, New York, NY 10016, United States of America.
| | - James Babb
- Alzheimer's Disease Research Center, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
| | - Natalie Saba
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
| | - Ludovic Debure
- Alzheimer's Disease Research Center, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
| | - Andrew W Varga
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, United States of America.
| | - Indu Ayappa
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, United States of America.
| | - David M Rapoport
- Mount Sinai Integrative Sleep Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, United States of America.
| | - Tracy A Butler
- Department of Neurology, Weill Cornell Medicine, New York, NY 10065, United States of America.
| | - Mony J de Leon
- Department of Neurology, Weill Cornell Medicine, New York, NY 10065, United States of America.
| | - Thomas Wisniewski
- Alzheimer's Disease Research Center, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
| | - Brian J Lopresti
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15213, United States of America.
| | - Ricardo S Osorio
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY 10016, United States of America; Alzheimer's Disease Research Center, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, United States of America.
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7
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Khrapunov S, Waterman A, Persaud R, Chang EP. Structure, Function, and Thermodynamics of Lactate Dehydrogenases from Humans and the Malaria Parasite P. falciparum. Biochemistry 2021; 60:3582-3595. [PMID: 34747601 DOI: 10.1021/acs.biochem.1c00470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Temperature adaptation is ubiquitous among all living organisms, yet the molecular basis for this process remains poorly understood. It can be assumed that for parasite-host systems, the same enzymes found in both organisms respond to the same selection factor (human body temperature) with similar structural changes. Herein, we report the existence of a reversible temperature-dependent structural transition for the glycolytic enzyme lactate dehydrogenase (LDH) from the malaria parasite Plasmodium falciparum (pfLDH) and human heart (hhLDH) occurring in the temperature range of human fever. This transition is observed for LDHs from psychrophiles, mesophiles, and moderate thermophiles in their operating temperature range. Thermodynamic analysis reveals unique thermodynamic signatures of the LDH-substrate complexes defining a specific temperature range to which human LDH is adapted and parasite LDH is not, despite their common mesophilic nature. The results of spectroscopic analysis combined with the available crystallographic data reveal the existence of an active center within pfLDH that imparts psychrophilic structural properties to the enzyme. This center consists of two pockets, one formed by the five amino acids (5AA insert) within the substrate specificity loop and the other by the active site, that mutually regulate one another in response to temperature and induce structural and functional changes in the Michaelis complex. Our findings pave the way toward a new strategy for malaria treatments and drug design using therapeutic agents that inactivate malarial LDH selectively at a specific temperature range of the cyclic malaria paroxysm.
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Affiliation(s)
- Sergei Khrapunov
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Akiba Waterman
- Department of Chemistry and Physical Sciences, Pace University, 1 Pace Plaza, New York, New York 10038, United States
| | - Rudra Persaud
- Department of Chemistry and Physical Sciences, Pace University, 1 Pace Plaza, New York, New York 10038, United States
| | - Eric P Chang
- Department of Chemistry and Physical Sciences, Pace University, 1 Pace Plaza, New York, New York 10038, United States
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8
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Marguerite NT, Bernard J, Harrison DA, Harris D, Cooper RL. Effect of Temperature on Heart Rate for Phaenicia sericata and Drosophila melanogaster with Altered Expression of the TrpA1 Receptors. INSECTS 2021; 12:38. [PMID: 33418937 PMCID: PMC7825143 DOI: 10.3390/insects12010038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 12/24/2020] [Accepted: 01/02/2021] [Indexed: 11/29/2022]
Abstract
The transient receptor potential (TrpA-ankyrin) receptor has been linked to pathological conditions in cardiac function in mammals. To better understand the function of the TrpA1 in regulation of the heart, a Drosophila melanogaster model was used to express TrpA1 in heart and body wall muscles. Heartbeat of in intact larvae as well as hearts in situ, devoid of hormonal and neural input, indicate that strong over-expression of TrpA1 in larvae at 30 or 37 °C stopped the heart from beating, but in a diastolic state. Cardiac function recovered upon cooling after short exposure to high temperature. Parental control larvae (UAS-TrpA1) increased heart rate transiently at 30 and 37 °C but slowed at 37 °C within 3 min for in-situ preparations, while in-vivo larvae maintained a constant heart rate. The in-situ preparations maintained an elevated rate at 30 °C. The heartbeat in the TrpA1-expressing strains could not be revived at 37 °C with serotonin. Thus, TrpA1 activation may have allowed enough Ca2+ influx to activate K(Ca) channels into a form of diastolic stasis. TrpA1 activation in body wall muscle confirmed a depolarization of membrane. In contrast, blowfly Phaenicia sericata larvae increased heartbeat at 30 and 37 °C, demonstrating greater cardiac thermotolerance.
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Affiliation(s)
- Nicole T. Marguerite
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA; (N.T.M.); (J.B.); (D.A.H.)
| | - Jate Bernard
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA; (N.T.M.); (J.B.); (D.A.H.)
| | - Douglas A. Harrison
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA; (N.T.M.); (J.B.); (D.A.H.)
| | | | - Robin L. Cooper
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA; (N.T.M.); (J.B.); (D.A.H.)
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9
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Comparative characterization of the hemocyanin-derived phenol oxidase activity from spiders inhabiting different thermal habitats. Comp Biochem Physiol B Biochem Mol Biol 2021; 253:110548. [PMID: 33388391 DOI: 10.1016/j.cbpb.2020.110548] [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] [Received: 09/21/2020] [Revised: 12/07/2020] [Accepted: 12/14/2020] [Indexed: 11/23/2022]
Abstract
Enzymes adapted to cold temperatures are commonly characterized for having higher Michaelis-Menten constants (KM) values and lower optimum and denaturation temperature, when compared to other meso or thermophilic enzymes. Phenoloxidase (PO) enzymes are ubiquitous in nature, however, they have not been reported in spiders. It is the oxygen carrier protein hemocyanin (Hc), found at high concentrations in their hemolymph, which displays an inducible PO activity. Hence, we hypothesize that Hc-derived PO activity could show features of cold adaptation in alpine species. We analyzed the Hc from two species of Theraphosidae from different thermal environments: Euathlus condorito (2400 m a.s.l.) and Grammostola rosea (500 m a.s.l.). Hc was purified from the hemolymph of both spiders and was characterized by identifying subunit composition and measuring the sodium dodecyl sulfate (SDS)-induced PO activity. The high-altitude spider Hc showed higher PO activity under all conditions and higher apparent Michaelis-Menten constant. Moreover, the optimum temperature for PO activity was lower for E. condorito Hc. These findings suggest a potential adaptation at the level of Hc-derived PO activity in Euathlus condorito, giving insights on possible mechanisms used by this mygalomorph spider to occupy extremes and variable thermal environments.
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Miller WT. Temperature sensitivities of metazoan and pre-metazoan Src kinases. Biochem Biophys Rep 2020; 23:100775. [PMID: 32566764 PMCID: PMC7298416 DOI: 10.1016/j.bbrep.2020.100775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/01/2020] [Accepted: 06/04/2020] [Indexed: 11/24/2022] Open
Abstract
Homologous enzymes from different species display functional characteristics that correlate with the physiological and environmental temperatures encountered by the organisms. In this study, we have investigated the temperature sensitivity of the nonreceptor tyrosine kinase Src. We compared the temperature dependencies of c-Src and two Src kinases from single-celled eukaryotes, the choanoflagellate Monosiga brevicollis and the filasterean Capsaspora owczarzaki. Metazoan c-Src exhibits temperature sensitivity, with high activity at 30 °C and 37 °C. This sensitivity is driven by changes in substrate binding as well as maximal velocity, and it is dependent on the amino acid sequence surrounding tyrosine in the substrate. When tested with a peptide that displays temperature-dependent phosphorylation by c-Src, the enzymatic rates for the unicellular Src kinases show much less variation over the temperatures tested. The data demonstrate that unicellular Src kinases are temperature compensated relative to metazoan c-Src, consistent with an evolutionary adaptation to their environments.
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Affiliation(s)
- W. Todd Miller
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794, USA
- Department of Veterans Affairs Medical Center, Northport, NY, 11768, USA
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11
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Neel LK, Curlis JD, Kinsey CT, Cox CL, McBrayer LD. Acclimatization in the physiological performance of an introduced ectotherm. J Exp Biol 2020; 223:jeb201517. [PMID: 32098885 DOI: 10.1242/jeb.201517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 02/17/2020] [Indexed: 01/06/2023]
Abstract
Phenotypic flexibility may facilitate range expansion by allowing organisms to maintain high levels of performance when introduced to novel environments. Phenotypic flexibility, such as reversible acclimatization, permits organisms to achieve high performance over a wide range of environmental conditions, without the costly allocation or acquisition tradeoffs associated with behavioral thermoregulation, which may expedite range expansion in introduced species. The northern curly-tailed lizard, Leiocephalus carinatus, was introduced to the USA in the 1940s and is now established in southern Florida. We measured bite force and the thermal sensitivity of sprinting of L. carinatus during the winter and spring to determine how morphology and performance varied seasonally. We found evidence of seasonal variation in several aspects of physiological performance. Lizards sampled in spring sprinted faster and tolerated higher temperatures, while lizards sampled in winter had high performance over a wider range of temperatures. Furthermore, seasonal differences in physiology were only detected after generating thermal reaction norms. Both sprint and bite force performance did not differ seasonally when solely comparing performance at a common temperature. No seasonal relationships between morphology and performance were detected. Our results suggest that L. carinatus may use reversible acclimatization to maintain high levels of performance across seasons not typically experienced within their native range. Thermal physiology plasticity may ameliorate the impacts of sub-optimal temperatures on performance without the cost of behavioral thermoregulation. Our work highlights the importance of utilizing reaction norms when evaluating performance and the potential ecological impacts of introduced species.
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Affiliation(s)
- Lauren K Neel
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
| | - John D Curlis
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chase T Kinsey
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
| | - Christian L Cox
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA
| | - Lance D McBrayer
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
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12
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Christen F, Dufresne F, Leduc G, Dupont-Cyr BA, Vandenberg GW, Le François NR, Tardif JC, Lamarre SG, Blier PU. Thermal tolerance and fish heart integrity: fatty acids profiles as predictors of species resilience. CONSERVATION PHYSIOLOGY 2020; 8:coaa108. [PMID: 33408863 PMCID: PMC7771578 DOI: 10.1093/conphys/coaa108] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/21/2020] [Accepted: 11/20/2020] [Indexed: 05/05/2023]
Abstract
The cardiovascular system is a major limiting system in thermal adaptation, but the exact physiological mechanisms underlying responses to thermal stress are still not completely understood. Recent studies have uncovered the possible role of reactive oxygen species production rates of heart mitochondria in determining species' upper thermal limits. The present study examines the relationship between individual response to a thermal challenge test (CTmax), susceptibility to peroxidation of membrane lipids, heart fatty acid profiles and cardiac antioxidant enzyme activities in two salmonid species from different thermal habitats (Salvelinus alpinus, Salvelinus fontinalis) and their hybrids. The susceptibility to peroxidation of membranes in the heart was negatively correlated with individual thermal tolerance. The same relationship was found for arachidonic and eicosapentaenoic acid. Total H2O2 buffering activity of the heart muscle was higher for the group with high thermal resistance. These findings underline a potential general causative relationship between sensitivity to oxidative stress, specific fatty acids, antioxidant activity in the cardiac muscle and thermal tolerance in fish and likely other ectotherms. Heart fatty acid profile could be indicative of species resilience to global change, and more importantly the plasticity of this trait could predict the adaptability of fish species or populations to changes in environmental temperature.
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Affiliation(s)
- Felix Christen
- Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada
| | - France Dufresne
- Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada
| | - Gabriel Leduc
- Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada
| | - Bernard A Dupont-Cyr
- Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada
| | - Grant W Vandenberg
- Département de Sciences Animales, Université Laval, Québec, Québec, G1V 0A6, Canada
| | | | - Jean-Claude Tardif
- Montreal Heart Institute, Université de Montréal, Montréal, Québec, H1T 1C8, Canada
| | - Simon G Lamarre
- Département de Biologie, Université de Moncton, Moncton, New-Brunswick, E1A 3E9, Canada
| | - Pierre U Blier
- Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada
- Corresponding author: Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, G5L3A1, Canada.
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13
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Rodgers EM, Poletto JB, Gomez Isaza DF, Van Eenennaam JP, Connon RE, Todgham AE, Seesholtz A, Heublein JC, Cech JJ, Kelly JT, Fangue NA. Integrating physiological data with the conservation and management of fishes: a meta-analytical review using the threatened green sturgeon ( Acipenser medirostris). CONSERVATION PHYSIOLOGY 2019; 7:coz035. [PMID: 31281658 PMCID: PMC6601218 DOI: 10.1093/conphys/coz035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/26/2019] [Accepted: 05/20/2019] [Indexed: 05/04/2023]
Abstract
Reversing global declines in the abundance and diversity of fishes is dependent on science-based conservation solutions. A wealth of data exist on the ecophysiological constraints of many fishes, but much of this information is underutilized in recovery plans due to a lack of synthesis. Here, we used the imperiled green sturgeon (Acipenser medirostris) as an example of how a quantitative synthesis of physiological data can inform conservation plans, identify knowledge gaps and direct future research actions. We reviewed and extracted metadata from peer-reviewed papers on green sturgeon. A total of 105 publications were identified, spanning multiple disciplines, with the primary focus being conservation physiology (23.8%). A meta-analytical approach was chosen to summarize the mean effects of prominent stressors (elevated temperatures, salinity, low food availability and contaminants) on several physiological traits (growth, thermal tolerance, swimming performance and heat shock protein expression). All examined stressors significantly impaired green sturgeon growth, and additional stressor-specific costs were documented. These findings were then used to suggest several management actions, such as mitigating salt intrusion in nursery habitats and maintaining water temperatures within optimal ranges during peak spawning periods. Key data gaps were also identified; research efforts have been biased towards juvenile (38.1%) and adult (35.2%) life-history stages, and less data are available for early life-history stages (embryonic, 11.4%; yolk-sac larvae, 12.4%; and post yolk-sac larvae, 16.2%). Similarly, most data were collected from single-stressor studies (91.4%) and there is an urgent need to understand interactions among stressors as anthropogenic change is multi-variate and dynamic. Collectively, these findings provide an example of how meta-analytic reviews are a powerful tool to inform management actions, with the end goal of maximizing conservation gains from research efforts.
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Affiliation(s)
- Essie M Rodgers
- Wildlife, Fish and Conservation Biology, University of California Davis, One Shields Ave., Davis, CA, USA
| | - Jamilynn B Poletto
- School of Natural Resources, University of Nebraska-Lincoln, 3310 Holdrege St., Lincoln, NE, USA
| | - Daniel F Gomez Isaza
- School of Biological Sciences, The University Queensland, Brisbane, QLD, Australia
| | - Joel P Van Eenennaam
- Department of Animal Science, University of California Davis, One Shields Ave., Davis, CA, USA
| | - Richard E Connon
- Department of Anatomy, Physiology and Cell Biology, University of California Davis, One Shields Ave., Davis, CA, USA
| | - Anne E Todgham
- Department of Animal Science, University of California Davis, One Shields Ave., Davis, CA, USA
| | - Alicia Seesholtz
- California Department of Water Resources, Industrial Blvd., West Sacramento, CA, USA
| | - Joe C Heublein
- NOAA National Marine Fisheries Program, West Coast Region, Capital Mall, Sacramento, CA, USA
| | - Joseph J Cech
- Wildlife, Fish and Conservation Biology, University of California Davis, One Shields Ave., Davis, CA, USA
| | - John T Kelly
- Fisheries Branch, California Department of Fish and Wildlife, Sacramento, CA, USA
| | - Nann A Fangue
- Wildlife, Fish and Conservation Biology, University of California Davis, One Shields Ave., Davis, CA, USA
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14
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Sasaki M, Hedberg S, Richardson K, Dam HG. Complex interactions between local adaptation, phenotypic plasticity and sex affect vulnerability to warming in a widespread marine copepod. ROYAL SOCIETY OPEN SCIENCE 2019; 6:182115. [PMID: 31032052 PMCID: PMC6458359 DOI: 10.1098/rsos.182115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/27/2019] [Indexed: 05/06/2023]
Abstract
Predicting the response of populations to climate change requires an understanding of how various factors affect thermal performance. Genetic differentiation is well known to affect thermal performance, but the effects of sex and developmental phenotypic plasticity often go uncharacterized. We used common garden experiments to test for effects of local adaptation, developmental phenotypic plasticity and individual sex on thermal performance of the ubiquitous copepod, Acartia tonsa (Calanoida, Crustacea) from two populations strongly differing in thermal regimes (Florida and Connecticut, USA). Females had higher thermal tolerance than males in both populations, while the Florida population had higher thermal tolerance compared with the Connecticut population. An effect of developmental phenotypic plasticity on thermal tolerance was observed only in the Connecticut population. Our results show clearly that thermal performance is affected by complex interactions of the three tested variables. Ignoring sex-specific differences in thermal performance may result in a severe underestimation of population-level impacts of warming because of population decline due to sperm limitation. Furthermore, despite having a higher thermal tolerance, low-latitude populations may be more vulnerable to warming as they lack the ability to respond to increases in temperature through phenotypic plasticity.
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Affiliation(s)
- Matthew Sasaki
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
- Author for correspondence: Matthew Sasaki e-mail:
| | | | | | - Hans G. Dam
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
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15
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Pischedda A, Ramasamy KP, Mangiagalli M, Chiappori F, Milanesi L, Miceli C, Pucciarelli S, Lotti M. Antarctic marine ciliates under stress: superoxide dismutases from the psychrophilic Euplotes focardii are cold-active yet heat tolerant enzymes. Sci Rep 2018; 8:14721. [PMID: 30283056 PMCID: PMC6170424 DOI: 10.1038/s41598-018-33127-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/20/2018] [Indexed: 11/09/2022] Open
Abstract
Oxidative stress is a particularly severe threat to Antarctic marine polar organisms because they are exposed to high dissolved oxygen and to intense UV radiation. This paper reports the features of three superoxide dismutases from the Antarctic psychrophilic ciliate Euplotes focardii that faces two environmental challenges, oxidative stress and low temperature. Two out of these are Cu,Zn superoxide dismutases (named Ef-SOD1a and Ef-SOD1b) and one belongs to the Mn-containing group (Ef-SOD2). Ef-SOD1s and Ef-SOD2 differ in their evolutionary history, expression and overall structural features. Ef-SOD1 genes are expressed at different levels, with Ef-SOD1b mRNA 20-fold higher at the ciliate optimal temperature of growth (4 °C). All Ef-SOD enzymes are active at 4 °C, consistent with the definition of cold-adapted enzymes. At the same time, they display temperatures of melting in the range 50-70 °C and retain residual activity after incubation at 65-75 °C. Supported by data of molecular dynamics simulation, we conclude that the E. focardii SODs combine cold activity, local molecular flexibility and thermo tolerance.
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Affiliation(s)
- Alessandro Pischedda
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
| | - Kesava Priyan Ramasamy
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile III da Varano, 1, 62032, Camerino (MC), Italy
| | - Marco Mangiagalli
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
| | | | | | - Cristina Miceli
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile III da Varano, 1, 62032, Camerino (MC), Italy
| | - Sandra Pucciarelli
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile III da Varano, 1, 62032, Camerino (MC), Italy.
| | - Marina Lotti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
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16
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Jessop TS, Lane M, Wilson RS, Narayan EJ. Testing for Short- and Long-Term Thermal Plasticity in Corticosterone Responses of an Ectothermic Vertebrate. Physiol Biochem Zool 2018; 91:967-975. [PMID: 29863953 DOI: 10.1086/698664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Phenotypic plasticity, broadly defined as the capacity of one genotype to produce more than one phenotype, is a key mechanism for how animals adapt to environmental (including thermal) variation. Vertebrate glucocorticoid hormones exert broad-scale regulation of physiological, behavioral, and morphological traits that influence fitness under many life-history or environmental contexts. Yet the capacity for vertebrates to demonstrate different types of thermal plasticity, including rapid compensation or longer acclimation in glucocorticoid hormone function, when subject to different environmental temperature regimes remains poorly addressed. Here, we explore whether patterns of urinary corticosterone metabolites respond (i.e., evidence of acclimation) to repeated short-term and sustained long-term temperature exposures in an amphibian, the cane toad (Rhinella marina). In response to three repeated short (30-min) high-temperature (37°C) exposures (at 10-d intervals), toads produced urinary corticosterone metabolite responses of sequentially greater magnitude, relative to controls. However, toads subjected to 4 wk of acclimation to either cool (18°C)- or warm (30°C)-temperature environments did not differ significantly in their urinary corticosterone metabolite responses during exposure to a thermal ramp (18°-36°C). Together, these results indicate that adult toads had different, including limited, capacities for their glucocorticoid responses to demonstrate plasticity to different regimes of environmental temperature variation. We advocate further research as necessary to identify plasticity, or lack thereof, in glucocorticoid physiology, to better understand how vertebrates can regulate organismal responses to environmental variation.
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Affiliation(s)
- Tim S Jessop
- 1 Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Geelong, Victoria 3220, Australia
| | - Meagan Lane
- 2 School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Robbie S Wilson
- 3 School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Edward J Narayan
- 4 School of Science and Health, Hawkesbury campus, Western Sydney University, Locked Bag 1797, Penrith, New South Wales 2751, Australia
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17
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Christen F, Desrosiers V, Dupont-Cyr BA, Vandenberg GW, Le François NR, Tardif JC, Dufresne F, Lamarre SG, Blier PU. Thermal tolerance and thermal sensitivity of heart mitochondria: Mitochondrial integrity and ROS production. Free Radic Biol Med 2018; 116:11-18. [PMID: 29294390 DOI: 10.1016/j.freeradbiomed.2017.12.037] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/17/2017] [Accepted: 12/29/2017] [Indexed: 12/21/2022]
Abstract
Cardiac mitochondrial metabolism provides 90% of the ATP necessary for the contractile exertion of the heart muscle. Mitochondria are therefore assumed to play a pivotal role in heart failure (HF), cardiovascular disease and ageing. Heat stress increases energy metabolism and oxygen demand in tissues throughout the body and imposes a major challenge on the heart, which is suspected of being the first organ to fail during heat stress. The underlying mechanisms inducing heart failure are still unclear. To pinpoint the processes implicated in HF during heat stress, we measured mitochondrial respiration rates and hydrogen peroxide production of isolated Arctic char (Salvelinus alpinus) heart mitochondria at 4 temperatures: 10°C (acclimation), 15°C, 20°C and 25°C (just over critical maximum). We found that at temperature ranges causing the loss of an organism's general homeostasis (between 20°C and 25°C) and with a substrate combination close to physiological conditions, the heat-induced increase in mitochondrial oxygen consumption levels off. More importantly, at the same state, hydrogen peroxide efflux increased by almost 50%. In addition, we found that individuals with low mitochondrial respiration rates produced more hydrogen peroxide at 10°C, 15°C and 20°C. This could indicate that individuals with cardiac mitochondria having a low respiratory capacity, have a more fragile heart and will be more prone to oxidative stress and HF, and less tolerant to temperature changes and other stressors. Our results show that, at temperatures close to the thermal limit, mitochondrial capacity is compromised and ROS production rates increase. This could potentially alter the performance of the cardiac muscle and lead to heat-induced HF underlining the important role that mitochondria play in setting thermal tolerance limits.
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Affiliation(s)
- Felix Christen
- Université du Québec à Rimouski, Département de biologie, Rimouski, Québec, Canada G5L3A1
| | - Véronique Desrosiers
- Université du Québec à Rimouski, Département de biologie, Rimouski, Québec, Canada G5L3A1
| | - Bernard A Dupont-Cyr
- Université du Québec à Rimouski, Département de biologie, Rimouski, Québec, Canada G5L3A1
| | - Grant W Vandenberg
- Université Laval, Département de sciences animales, Québec, Canada G1V 0A6
| | | | - Jean-Claude Tardif
- Montreal Heart Institute, Université de Montréal, Montréal, Québec, Canada H1T 1C8
| | - France Dufresne
- Université du Québec à Rimouski, Département de biologie, Rimouski, Québec, Canada G5L3A1
| | - Simon G Lamarre
- Université de Moncton, Département de biologie, Moncton, New-Brunswick, Canada E1A 3E9
| | - Pierre U Blier
- Université du Québec à Rimouski, Département de biologie, Rimouski, Québec, Canada G5L3A1.
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18
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Miller SR. An appraisal of the enzyme stability‐activity trade‐off. Evolution 2017; 71:1876-1887. [DOI: 10.1111/evo.13275] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 05/09/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Scott R. Miller
- Division of Biological SciencesThe University of Montana Missoula Montana 59812
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19
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Jessop TS, Lane ML, Teasdale L, Stuart-Fox D, Wilson RS, Careau V, Moore IT. Multiscale Evaluation of Thermal Dependence in the Glucocorticoid Response of Vertebrates. Am Nat 2016; 188:342-56. [DOI: 10.1086/687588] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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20
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Yonezawa M, Nakagawa M, Nakamura S, Goto T, Sugawara K, Kidokoro SI, Wakui H, Nunomura W. Conserved and unique thermodynamic properties of lactate dehydrogenases in an ectothermic organism, the teleostMicrostomus achne, and an endothermic organism, bovine. J Biochem 2016; 160:299-308. [DOI: 10.1093/jb/mvw039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/22/2016] [Indexed: 11/13/2022] Open
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21
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Abstract
All true metazoans modify their RNAs by converting specific adenosine residues to inosine. Because inosine binds to cytosine, it is a biological mimic for guanosine. This subtle change, termed RNA editing, can have diverse effects on various RNA-mediated cellular pathways, including RNA interference, innate immunity, retrotransposon defense and messenger RNA recoding. Because RNA editing can be regulated, it is an ideal tool for increasing genetic diversity, adaptation and environmental acclimation. This review will cover the following themes related to RNA editing: (1) how it is used to modify different cellular RNAs, (2) how frequently it is used by different organisms to recode mRNA, (3) how specific recoding events regulate protein function, (4) how it is used in adaptation and (5) emerging evidence that it can be used for acclimation. Organismal biologists with an interest in adaptation and acclimation, but with little knowledge of RNA editing, are the intended audience.
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Affiliation(s)
- Joshua J C Rosenthal
- Universidad de Puerto Rico, Recinto de Ciencias Medicas, Instituto de Neurobiologia, 201 Blvd. del Valle, San Juan, PR 00901, USA
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22
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Torday JS. Life Is Simple-Biologic Complexity Is an Epiphenomenon. BIOLOGY 2016; 5:E17. [PMID: 27128951 PMCID: PMC4929531 DOI: 10.3390/biology5020017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/29/2016] [Accepted: 04/20/2016] [Indexed: 12/30/2022]
Abstract
Life originated from unicellular organisms by circumventing the Second Law of Thermodynamics using the First Principles of Physiology, namely negentropy, chemiosmosis and homeostatic regulation of calcium and lipids. It is hypothesized that multicellular organisms are merely contrivances or tools, used by unicellular organisms as agents for the acquisition of epigenetic inheritance. The First Principles of Physiology, which initially evolved in unicellular organisms are the exapted constraints that maintain, sustain and perpetuate that process. To ensure fidelity to this mechanism, we must return to the first principles of the unicellular state as the determinants of the primary level of selection pressure during the life cycle. The power of this approach is reflected by examples of its predictive value. This perspective on life is a "game changer", mechanistically rendering transparent many dogmas, teleologies and tautologies that constrain the current descriptive view of Biology.
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Affiliation(s)
- John S Torday
- Evolutionary Medicine Program, University of California, Los Angeles, CA 90095, USA.
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23
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Martinez E, Porreca A, Colombo R, Menze M. Tradeoffs of warm adaptation in aquatic ectotherms: Live fast, die young? Comp Biochem Physiol A Mol Integr Physiol 2016; 191:209-215. [DOI: 10.1016/j.cbpa.2015.07.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 07/23/2015] [Accepted: 07/27/2015] [Indexed: 10/23/2022]
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24
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Fields PA, Dong Y, Meng X, Somero GN. Adaptations of protein structure and function to temperature: there is more than one way to ‘skin a cat’. J Exp Biol 2015; 218:1801-11. [DOI: 10.1242/jeb.114298] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
ABSTRACT
Sensitivity to temperature helps determine the success of organisms in all habitats, and is caused by the susceptibility of biochemical processes, including enzyme function, to temperature change. A series of studies using two structurally and catalytically related enzymes, A4-lactate dehydrogenase (A4-LDH) and cytosolic malate dehydrogenase (cMDH) have been especially valuable in determining the functional attributes of enzymes most sensitive to temperature, and identifying amino acid substitutions that lead to changes in those attributes. The results of these efforts indicate that ligand binding affinity and catalytic rate are key targets during temperature adaptation: ligand affinity decreases during cold adaptation to allow more rapid catalysis. Structural changes causing these functional shifts often comprise only a single amino acid substitution in an enzyme subunit containing approximately 330 residues; they occur on the surface of the protein in or near regions of the enzyme that move during catalysis, but not in the active site; and they decrease stability in cold-adapted orthologs by altering intra-molecular hydrogen bonding patterns or interactions with the solvent. Despite these structure–function insights, we currently are unable to predict a priori how a particular substitution alters enzyme function in relation to temperature. A predictive ability of this nature might allow a proteome-wide survey of adaptation to temperature and reveal what fraction of the proteome may need to adapt to temperature changes of the order predicted by global warming models. Approaches employing algorithms that calculate changes in protein stability in response to a mutation have the potential to help predict temperature adaptation in enzymes; however, using examples of temperature-adaptive mutations in A4-LDH and cMDH, we find that the algorithms we tested currently lack the sensitivity to detect the small changes in flexibility that are central to enzyme adaptation to temperature.
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Affiliation(s)
- Peter A. Fields
- Biology Department, Franklin & Marshall College, Lancaster, PA 17603, USA
| | - Yunwei Dong
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China
| | - Xianliang Meng
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - George N. Somero
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA 93940, USA
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25
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Schulte PM. The effects of temperature on aerobic metabolism: towards a mechanistic understanding of the responses of ectotherms to a changing environment. J Exp Biol 2015; 218:1856-66. [DOI: 10.1242/jeb.118851] [Citation(s) in RCA: 387] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
ABSTRACT
Because of its profound effects on the rates of biological processes such as aerobic metabolism, environmental temperature plays an important role in shaping the distribution and abundance of species. As temperature increases, the rate of metabolism increases and then rapidly declines at higher temperatures – a response that can be described using a thermal performance curve (TPC). Although the shape of the TPC for aerobic metabolism is often attributed to the competing effects of thermodynamics, which can be described using the Arrhenius equation, and the effects of temperature on protein stability, this account represents an over-simplification of the factors acting even at the level of single proteins. In addition, it cannot adequately account for the effects of temperature on complex multistep processes, such as aerobic metabolism, that rely on mechanisms acting across multiple levels of biological organization. The purpose of this review is to explore our current understanding of the factors that shape the TPC for aerobic metabolism in response to acute changes in temperature, and to highlight areas where this understanding is weak or insufficient. Developing a more strongly grounded mechanistic model to account for the shape of the TPC for aerobic metabolism is crucial because these TPCs are the foundation of several recent attempts to predict the responses of species to climate change, including the metabolic theory of ecology and the hypothesis of oxygen and capacity-limited thermal tolerance.
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26
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Gunderson AR, Stillman JH. An affinity for biochemical adaptation to temperature. J Exp Biol 2014; 217:4273-4. [DOI: 10.1242/jeb.103192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Alex R. Gunderson
- San Francisco State University and University of California Berkeley
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27
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Iftikar FI, Hickey AJR. Do mitochondria limit hot fish hearts? Understanding the role of mitochondrial function with heat stress in Notolabrus celidotus. PLoS One 2013; 8:e64120. [PMID: 23724026 PMCID: PMC3665896 DOI: 10.1371/journal.pone.0064120] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/10/2013] [Indexed: 11/05/2022] Open
Abstract
Hearts are the first organs to fail in animals exposed to heat stress. Predictions of climate change mediated increases in ocean temperatures suggest that the ectothermic heart may place tight constraints on the diversity and distribution of marine species with cardiovascular systems. For many such species, their upper temperature limits (Tmax) and respective heart failure (HF) temperature (T(HF)) are only a few degrees from current environmental temperatures. While the ectothermic cardiovascular system acts as an "ecological thermometer," the exact mechanism that mediates HF remains unresolved. We propose that heat-stressed cardiac mitochondria drive HF. Using a common New Zealand fish, Notolabrus celidotus, we determined the THF (27.5°C). Haemoglobin oxygen saturation appeared to be unaltered in the blood surrounding and within heat stressed hearts. Using high resolution respirometry coupled to fluorimeters, we explored temperature-mediated changes in respiration, ROS and ATP production, and overlaid these changes with T(HF). Even at saturating oxygen levels several mitochondrial components were compromised before T(HF). Importantly, the capacity to efficiently produce ATP in the heart is limited at 25°C, and this is prior to the acute T(HF) for N. celidotus. Membrane leakiness increased significantly at 25°C, as did cytochrome c release and permeability to NADH. Maximal flux rates and the capacity for the electron transport system to uncouple were also altered at 25°C. These data indicate that mitochondrial membrane integrity is lost, depressing ATP synthesis capacity and promoting cytochrome c release, prior to T(HF). Mitochondria can mediate HF in heat stressed hearts in fish and play a significant role in thermal stress tolerance, and perhaps limit species distributions by contributing to HF.
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Affiliation(s)
- Fathima I. Iftikar
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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28
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Brown AC, da Silva FM. ACUTE METABOLIC RATE: TEMPERATURE RELATIONSHIPS OF INTACT AND HOMOGENIZEDBULLIA DIGITALIS(GASTROPODA, NASSARIIDAE). ACTA ACUST UNITED AC 2010. [DOI: 10.1080/00359198309520097] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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29
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Pedersen KS, Codrea MC, Vermeulen CJ, Loeschcke V, Bendixen E. Proteomic characterization of a temperature-sensitive conditional lethal in Drosophila melanogaster. Heredity (Edinb) 2009; 104:125-34. [PMID: 19812620 DOI: 10.1038/hdy.2009.132] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Genetic variation that is expressed only under specific environmental conditions can contribute to additional adverse effects of inbreeding if environmental conditions change. We present a proteomic characterization of a conditional lethal found in an inbred line of Drosophila melanogaster. The lethal effect is apparent as a large increase in early mortality at the restrictive temperature (29 degrees C) as opposed to normal survival at the permissive temperature (20 degrees C). The increased mortality in response to the restrictive temperature is probably caused by a single recessive major locus. A quantitative trait locus (QTL) region segregating variation affecting the lethal effect has been identified, allowing for a separation of primary/causal effects and secondary consequences in the proteome expression patterns observed. In this study, the proteomic response to the restrictive temperature in the lethal-line (L-line) was compared with the response in an inbred-control-line (IC-line) and an outbred-control-line (OC-line). Quantitative protein changes were detected using isobaric tags for relative and absolute quantitation (iTRAQ) two-dimensional liquid chromatography-tandem mass spectrometry. In all, 45 proteins were found to be significantly differently regulated in response to the restrictive temperature in the L-line as compared with the IC-line. No proteins were significantly differently regulated between the IC-line and the OC-line, verifying that differential protein regulation was specific to a genetic defect in the L-line. Proteins associated with oxidative phosphorylation and mitochondria were significantly overrepresented within the list of differentially expressed proteins. Proteins related to muscle contraction were also found to be differentially expressed in the L-line in response to the restrictive temperature, supporting phenotypic observations of moribund muscle hyper-contraction.
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Affiliation(s)
- K S Pedersen
- Department of Biological Sciences, Aarhus University, Aarhus C, Denmark.
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MEHRA A, SHI M, BAKER CL, COLOT HV, LOROS JJ, DUNLAP JC. CK2 and temperature compensation inNeurospora. Sleep Biol Rhythms 2009. [DOI: 10.1111/j.1479-8425.2009.00406.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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De Almeida‐Val VMF, Chippari Gomes AR, Lopes NP. Metabolic and Physiological Adjustments to Low Oxygen and High Temperature in Fishes of the Amazon. FISH PHYSIOLOGY 2005. [DOI: 10.1016/s1546-5098(05)21010-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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32
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Schulte PM. Changes in gene expression as biochemical adaptations to environmental change: a tribute to Peter Hochachka. Comp Biochem Physiol B Biochem Mol Biol 2004; 139:519-29. [PMID: 15544973 DOI: 10.1016/j.cbpc.2004.06.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2004] [Revised: 05/21/2004] [Accepted: 06/05/2004] [Indexed: 10/26/2022]
Abstract
Changes in gene expression are likely to play a critical role in both acclimation and adaptation to a changing environment. There is a rapidly growing body of literature implicating quantitative changes in gene expression during acclimation to environmental change, but less is known about the role of qualitative changes in gene expression, such as switching between alternative isoforms. Alternative isoforms can arise via gene duplication, alternative splicing, or alternative promoter usage. Organisms that have undergone recent genome duplication events may make use of environment-specific isoforms coded by multiple genes, but their role in other organisms is less well known. However, recent data suggest that isoforms arising from alternative splicing may be an under-appreciated source of physiological variation. The role of changes in gene expression during evolutionary adaptation has received comparatively limited attention, but novel approaches to addressing the adaptive significance of changes in gene expression have been applied to a few cases of differences in gene expression among taxa. Recent advances in genomics, including microarray technology, knock-out and knock-down approaches, and the wealth of data coming from large-scale sequencing projects have provided (and will continue to provide at ever increasing rates) new insights into these classic questions in comparative biochemistry.
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Affiliation(s)
- Patricia M Schulte
- Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4.
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Somero GN. Adaptation of enzymes to temperature: searching for basic “strategies”. Comp Biochem Physiol B Biochem Mol Biol 2004; 139:321-33. [PMID: 15544958 DOI: 10.1016/j.cbpc.2004.05.003] [Citation(s) in RCA: 207] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2004] [Revised: 05/14/2004] [Accepted: 05/20/2004] [Indexed: 10/26/2022]
Abstract
The pervasive influence of temperature on biological systems necessitates a suite of temperature--compensatory adaptations that span all levels of biological organization--from behavior to fine-scale molecular structure. Beginning about 50 years ago, physiological studies conducted with whole organisms or isolated tissues, by such pioneers of comparative thermal physiology as V.Ya. Alexandrov, T.H. Bullock, F.E.J. Fry, H. Precht, C.L. Prosser, and P.F. Scholander, began to document in detail the abilities of ectothermic animals to sustain relatively similar rates of metabolic activity at widely different temperatures of adaptation or acclimation. These studies naturally led to investigation of the roles played by enzymatic proteins in metabolic temperature compensation. Peter Hochachka's laboratory became an epicenter of this new focus in comparative physiology. The studies of the enzyme lactate dehydrogenase (LDH) that he initiated as a PhD student at Duke University in the mid-1960s and continued for several years at the University of British Columbia laid much of the foundation for subsequent studies of protein adaptation to temperature. Studies of orthologs of LDH have revealed the importance of conserving kinetic properties (catalytic rate constants (kcat) and Michaelis-Menten constants (Km) and structural stability during adaptation to temperature, and recently have identified the types of amino acid substitutions causing this adaptive variation. The roles of pH and low-molecular-mass organic solutes (osmolytes) in conserving the functional and structural properties of enzymes also have been elucidated using LDH. These studies, begun in Peter Hochachka's laboratory almost 40 years ago, have been instrumental in the development of a conceptual framework for the study of biochemical adaptation, a field whose origin can be traced largely to his creative influences. This framework emphasizes the complementary roles of three "strategies" of adaptation: (1) changes in amino acid sequence that cause adaptive variation in the kinetic properties and stabilities of proteins, (2) shifts in concentrations of proteins, which are mediated through changes in gene expression and protein turnover; and (3) changes in the milieu in which proteins function, which conserve the intrinsic properties of proteins established by their primary structure and modulate protein activity in response to physiological needs. This theoretical framework has helped guide research in adaptational biochemistry for many years and now stands poised to play a critical role in the post-genomic era, as physiologists grapple with the challenge of integrating the wealth of new data on gene sequences (genome), gene expression (transcriptome and proteome), and metabolic profiles (metabolome) into a realistic physiological context that takes into account the evolutionary histories and environmental relationships of species.
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Affiliation(s)
- George N Somero
- Department of Biological Sciences, Hopkins Marine Station, Stanford University, Oceanview Blvd., Pacific Grove, CA 93950, USA.
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Storey KB. Adventures in oxygen metabolism. Comp Biochem Physiol B Biochem Mol Biol 2004; 139:359-69. [PMID: 15544961 DOI: 10.1016/j.cbpc.2004.02.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2003] [Revised: 02/02/2004] [Accepted: 02/03/2004] [Indexed: 10/26/2022]
Abstract
Peter W. Hochachka led a grand life of science adventure and left as his legacy a whole new field--biochemical adaptation. Oxygen was at the core of Peter's career and his laboratory made major contributions to our understanding of how animals deal with variation in oxygen availability in many forms. He analyzed the molecular mechanisms that support facultative anaerobiosis, studied muscle exercise metabolism for high speed flight, swimming and running, investigated mammalian diving on many trips to the Antarctic to study Weddell seals, and probed the metabolic and genetic adaptations that provide optimal hypoxia tolerance for humans residing at high altitudes. His work illuminated both biochemical and physiological mechanisms that are used to optimize aerobic metabolism, to compensate for hypoxic insults, and to conserve energy by strong metabolic rate depression under anoxia. His articles, books and lectures galvanized the field with leading-edge insights and theories and he consistently challenged comparative biochemists to use their unique model systems to explore the range and breadth of animal strategies of biochemical adaptation. Lessons drawn from my training in Peter's laboratory have led me on continuing explorations of adaptations in enzyme function, signal transduction, gene expression, and antioxidant defenses ranging over systems of anoxia tolerance, freezing survival, estivation, and mammalian hibernation.
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Affiliation(s)
- Kenneth B Storey
- Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada K1S 5B6.
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Moon TW. Hormones and fish hepatocyte metabolism: “the good, the bad and the ugly!”. Comp Biochem Physiol B Biochem Mol Biol 2004; 139:335-45. [PMID: 15544959 DOI: 10.1016/j.cbpc.2004.06.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Revised: 05/31/2004] [Accepted: 06/10/2004] [Indexed: 11/18/2022]
Abstract
This short review examines some of my personal experiences with Dr. Peter Hochachka, as a mentor and friend, and how his encouragement led to the research undertaken in my laboratory over the past three decades. Specifically, our work using the fish hepatocyte preparation as a model cell system is reviewed. The hepatocyte is an ideal cellular system that can be used to probe hepatic physiology and biochemistry. The impact of insulin, glucagon and related peptides, and catecholamines is discussed from the perspective of core and diverse functions of these key vertebrate metabolic hormones. Each hormone that operates in fish species was studied in manners similar to that of mammals, but it appears that the role of glucagon-like peptide-1 (GLP-1) in particular differs substantially from that in mammals. The receptors for each of these fish hormones seem structurally and in some cases functionally quite distinct from those in mammals. Few fish hormone receptor sequences are available, but fish genomists are rapidly adding new sequence information to the existing databases, so our view of the evolution of vertebrate hormone receptors will become clearer very quickly.
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Affiliation(s)
- Thomas W Moon
- Department of Biology, University of Ottawa, PO Box 450, Stn A, Ottawa, ON, Canada K1N 6N5.
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Bowser PR, Wooster GA, St Leger J, Babish JG. Pharmacokinetics of enrofloxacin in fingerling rainbow trout (Oncorhynchus mykiss). J Vet Pharmacol Ther 1992; 15:62-71. [PMID: 1315398 DOI: 10.1111/j.1365-2885.1992.tb00987.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The pharmacokinetics of intravenously and orally administered enrofloxacin was determined in fingerling rainbow trout (Oncorhynchus mykiss). Doses of 5 or 10 mg enrofloxacin/kg body weight were administered intravenously to 26 fish for each dose and blood was sampled over a 60-h period at 15 degrees C. Two groups of fish were treated orally with 5, 10, or 50 mg/kg (80 fish/dose at each temperature) and held at 15 degrees C or 10 degrees C during the 60-h sampling period. Following intravenous administration, the serum concentration-time data of enrofloxacin in rainbow trout were best described by a two-compartment open model for both doses of 5 and 10 mg enrofloxacin/kg. The hybrid rate constants alpha and beta did not differ between doses. The distributional phase was rapid with a half-life of 6-7 min for both doses. Overall half-lives of elimination were 24.4 h (95% CI = 20.2-30.8) and 30.4 h (24.2-41.0), respectively, for the 5- and 10-mg/kg doses. A large Vd(area) was observed following dosing of either 5 or 10 mg enrofloxacin/kg,: 3.22 and 2.56 l/kg, respectively. Whole body clearance for 5 mg/kg was 92 ml/h.kg and 58 ml/h.kg at the 10-mg/kg dose. Following oral administration, the serum concentration-time data for enrofloxacin were best described as a one-compartment open model with first-order absorption and elimination. Apparent Ka over all doses at 10 degrees C averaged 62% less than apparent Ka at 15 degrees C. Estimates of the apparent t(1/2)e over both temperatures ranged from 29.5 h (18.4-73.4) to 56.3 h (38.3-106.6). Bioavailability averaged 42% over all doses at 15 degrees C and was decreased to an average of 25% at 10 degrees C. Peak serum concentrations appeared between 6 and 8 h following dosing. A dose of 5 mg/kg/day was estimated to provide average steady-state serum concentrations at 10 degrees C that are approximately 4.5 times the highest reported MIC values for Streptococcus spp., the fish pathogen least sensitive to enrofloxacin. Owing to the long apparent half-life of elimination of enrofloxacin in fingerling trout, it would take approximately 5 to 9 days to achieve these predicted steady-state serum concentrations; this estimate is important when considering the duration of therapy in clinical trials.
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Affiliation(s)
- P R Bowser
- Department of Avian and Aquatic Animal Medicine, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853
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Gildberg A, Olsen RL, Bjarnason JB. Characteristics and composition of pepsins from Atlantic cod. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 306:107-10. [PMID: 1812696 DOI: 10.1007/978-1-4684-6012-4_12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- A Gildberg
- Norwegian Institute of Fisheries and Aquculture, Tromso
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de Almeida-Val VMF, Schwantes MLB, Val AL. LDH isozymes in amazon Fish—I. Electrophoretic studies on two species from serrasalmidae family: Mylossoma duriventris and Colossoma macropomum. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/0305-0491(90)90251-n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Gildberg A, Olsen RL, Bjarnason JB. Catalytic properties and chemical composition of pepsins from Atlantic cod (Gadus morhua). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1990; 96:323-30. [PMID: 2113846 DOI: 10.1016/0305-0491(90)90382-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1. Three pepsins were purified from the gastric mucosa of Atlantic cod (Gadus morhua). 2. The enzymes, called Pepsin I and Pepsin IIa and b, had isoelectric points 6.9, 4.0 and 4.1, respectively, and digested hemoglobin at a maximal rate at a pH of approximately 3. 3. They resembled bovine cathepsin D in being unable to digest the mammalian pepsin substrate N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine. 4. Specificity constants (kcat/Km) for the cod pepsins were lower than for porcine pepsin, and they expressed higher substrate affinity and physiological efficiency at pH 3.5 than at pH 2. 5. The cod pepsins are glycoproteins, and their amino acid composition resembles that of porcine cathepsin D more than that of porcine pepsin. 6. The N-terminal sequence of Atlantic cod pepsins is substantially different from that of porcine pepsin. This indicates a significant evolutionary gap between fish and mammalian pepsins.
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Affiliation(s)
- A Gildberg
- Institute of Fisheries Technology Research, Tromsø, Norway
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41
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Fitch NA. Lactate dehydrogenase isozymes in the trunk and cardiac muscles of an antarctic teleost fish,Notothenia neglecta Nybelin. FISH PHYSIOLOGY AND BIOCHEMISTRY 1989; 6:187-195. [PMID: 24227074 DOI: 10.1007/bf01874775] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The distribution and kinetics of lactate dehydrogenase (LDH) isozymes in the red and white trunk muscles, and cardiac muscle of an antarctic teleost fish (Notothenia neglecta Nybelin) have been studied. Pyruvate inhibition of LDH in all three muscle types is very low, being less than 50% even at a concentration of 60mM pyruvate. Activity versus pyruvate concentration profiles are not significantly different for LDH in all three muscle types. The Michaelis constant (Km) for pyruvate was not significantly different for all three LDH's. Raising the assay temperature caused an increase in Km of similar form in all three muscle types, while Km was lowest at the lowest assay temperature (-1°C). When samples were run on a polyacrylamide gel, the bands stained specifically for LDH activity appeared at identical positions as those of the H2M2 band of the standards.It would appear therefore that the LDH isozyme found in the red and white trunk muscle ofN. neglecta is identical to that in cardiac muscle. This fact is discussed in relation to the physiological ecology of antaretic fishes, and the metabolic constraints imposed by their habitat, including their apparent low capacity for utilising glycolytic fuels.
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Affiliation(s)
- N A Fitch
- Department of Physiology and Pharmacology, Gatty Marine Laboratory, KY168LB, St. Andrews, Scotland
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Medina-Puerta MM, Gallego-Iniesta M, Garrido-Pertierra A. Kinetic analysis of 6-phosphogluconate dehydrogenase from bass liver: effects of temperature and pH on its catalytic function. Arch Biochem Biophys 1988; 262:130-41. [PMID: 3355163 DOI: 10.1016/0003-9861(88)90175-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Kinetic studies of the reaction between 6-phosphogluconate and NADP catalyzed by purified 6-phosphogluconate dehydrogenase from bass liver were made at pH 7.5 in Tris-HCl buffer. Relationships among the initial rate coefficients for 6-phosphogluconate, NADP, and Mg2+ suggest that the addition of Mg2+ and NADP to 6-phosphogluconate dehydrogenase does not follow an obligatory order, probably being random, in which 6-phosphogluconate combines second with the enzyme. The Michaelis constants for NADP, 6-phosphogluconate, and Mg2+ are 0.88 microM, 26.66 microM, and 3.33 mM, respectively. pK values for the enzyme-6-phosphogluconate and enzyme-NADP complexes have been obtained. The variations in the true Km values for NADP with pH are only threefold at most, and seem to be not especially significant. A plausible explanation for the physiological significance of the influence of temperature on the Km values is given. Kinetic studies show that phosphoenolpyruvate is a noncompetitive inhibitor of the enzyme with respect to 6-phosphogluconate and a competitive inhibitor with respect to NADP with Ki values of 0.54 mM against 6-phosphogluconate and 0.15 mM against NADP.
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Affiliation(s)
- M M Medina-Puerta
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain
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Marangos C, Ceccaldi HJ. Variations des concentrations des acides aminés libres des muscles abdominaux de Penaeus japonicus et Crangon crangon au cours d'acclimatations thermiques. BIOCHEM SYST ECOL 1988. [DOI: 10.1016/0305-1978(88)90020-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gildberg A. Aspartic proteinases in fishes and aquatic invertebrates. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1988; 91:425-35. [PMID: 3148385 DOI: 10.1016/0305-0491(88)90002-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
1. The literature on molecular properties and physiological role of aspartic proteinases in fishes and aquatic invertebrates has been reviewed. 2. Pepsins have not been detected in invertebrates, and apparently cathepsin D, as well as other cathepsins, act both as digestive and lysosomal enzymes in many of these animals. The molecular properties of invertebrate cathepsin D correspond with cathepsin D in fishes and mammalians. 3. Fishes with a true stomach have pepsinogen secretion. Fish pepsins have higher pH optimum and are less stable in strong acid conditions than mammalian pepsins. They are very efficient at low temperatures, but less thermostable than mammalian pepsins. 4. Many fishes have two significantly different pepsins: Pepsin I and Pepsin II, which digest haemoglobin at a maximal rate in the pH ranges 3-4 and 2-3 respectively. Usually the pI of Pepsin I is in the range 6.5-7, whereas pI of Pepsin II is about 4. 5. Fish Pepsin I and cathepsin D have very similar molecular properties, and a hypothesis proposing that cathepsin D is the ancestor enzyme of aspartic proteinases in higher animals is presented.
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Affiliation(s)
- A Gildberg
- Institute of Fishery Technology Research, Tromsø, Norway
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Ivanović J, Janković-Hladni M, Spasić V, Frušić M. Compensatory reactions at the level of digestive enzymes in relation to acclimatization in Morimus asper funereus larvae. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0300-9629(87)90320-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Alikhan MA, Martel M. Adaptation of enzymes to temperature: myofibrillar adenosine triphosphatase from two terrestrial isopod species. ARCHIVES INTERNATIONALES DE PHYSIOLOGIE ET DE BIOCHIMIE 1986; 94:187-91. [PMID: 2434048 DOI: 10.3109/13813458609071417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A comparison of the temperature profiles of the myofibrillar ATPase in Porcellio spinicornis and Metoponorthus pruinosus showed that Porcellio enzyme had a maximum activity between pH 6.8-7.2 at 9 degrees C, and that from Metoponorthus between pH 7.0-7.4 at 45 degrees C. The energy of activation for Porcellio enzyme was estimated to be 2.964 kcal/mol and that for Metoponorthus enzyme 9.91 X 10(-1) kcal/mol. The significance of these findings in relation to the natural habitats of these two species is discussed.
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Coppes Z. Isozymes of glucosephosphate isomerase (PGI) in fishes of the subclass actinopterygii. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1986; 84:575-88. [PMID: 3757487 DOI: 10.1016/0305-0491(86)90126-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A compilation of the species of fishes of the subclass Actinopterygii for the study of the PGI isozyme system is given. PGI appears to be codified by more than one locus in fishes; 65% of the species analysed here have two loci for PGI. PGI duplication in fishes and the relationship of isozymes of PGI with temperature and metabolism are discussed.
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Fideu MD, Herranz MJ, Ruíz-Amil M, Pérez ML. Pyruvate kinase of sea bass liver: interrelationship in regulating properties. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1986; 83:685-9. [PMID: 3956180 DOI: 10.1016/0305-0491(86)90318-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pyruvate kinase of sea bass liver show a joint modulation of both pH and temperature for PEP substrate. The effect of F-1,6-P2, alanine and ATP is not fundamentally affected by a variation in pH. The kinetic constants in the presence of ATP are not affected, but the intensity of its inhibitor effect varies with temperature. A study of different buffers: Tris-HC1, Tris-maleic and phosphate, on this enzymatic activity with or without effectors has been made.
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Fideu Alonso MD, Perez Perez ML, Ruiz Amil M, Herrauz Santos MJ. Regulation of liver sea bass pyruvate kinase by temperature, substrates and some metabolic effectors. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1985; 82:841-8. [PMID: 4092442 DOI: 10.1016/0305-0491(85)90533-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pyruvate kinase of sea bass (Dicentrarchus labrax L.) shows positive cooperativity with respect to both substrates PEP and ADP. The temperature is a modulator of this activity, changing KS0.5 and Hill coefficient values for PEP. The enzyme shows alanine and ATP inhibition and F-1,6-P2 activation at 22 degrees C. F-1,6-P2 eliminates the effect of alanine but not that of ATP. These results could indicate a regulation of this enzyme by temperature and possess kinetic properties which are similar to that of L-type mammals.
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Bizri M, Bouhours JF, Got R. Influence of temperature on the in vitro activity of GDP-mannose dolicholphosphate mannosyltransferase in rat and trout liver microsomes. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1985; 82:157-61. [PMID: 4053571 DOI: 10.1016/0305-0491(85)90146-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Temperature optimum of mannosyltransferase activity in liver microsomes is higher in trout than in rat, but this enzymatic activity for rat is higher than trout. Activation energies calculated for mannosyltransferase activity for trout and rat do not correlate with environmental temperature. For a given incubation temperature, Vm values for rat are higher than trout, whereas Km values for trout are lower than rat.
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