{"dp_type": "Dataset", "free_text": "Hemoglobin"}
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Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "locations": "Antarctica; Sub-Antarctic; Antarctica", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.", "uid": "601728", "west": -180.0}, {"awards": "1543383 Postlethwait, John; 1947040 Postlethwait, John; 2232891 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Fri, 08 Sep 2023 00:00:00 GMT", "description": "Notothenioid hemoglobin protein 3D modeling using SWISS-MODEL in the research article \u201cCold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\u201d by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "locations": "Sub-Antarctic; Antarctica", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Notothenioid hemoglobin protein 3D modeling.", "uid": "601732", "west": -180.0}, {"awards": "1543383 Postlethwait, John; 1947040 Postlethwait, John; 2232891 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Fri, 08 Sep 2023 00:00:00 GMT", "description": "Phylogenetic tree of Notothenioid species used in analyses and results of the HyPhy RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in the research article \u201cCold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\u201d by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "locations": "Antarctica; Sub-Antarctic", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.", "uid": "601731", "west": -180.0}, {"awards": "2232891 Postlethwait, John; 1543383 Postlethwait, John; 1947040 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Fri, 08 Sep 2023 00:00:00 GMT", "description": "Phylogenetic tree of Notothenioid species used in analyses and results of the HyPhy MEME tests for sites evolving under episodic diversifying selection in notothenioid hemoglobin genes in the research article \u201cCold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\u201d by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "locations": "Antarctica; Sub-Antarctic", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.", "uid": "601730", "west": -180.0}, {"awards": "2232891 Postlethwait, John; 1543383 Postlethwait, John; 1947040 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Fri, 08 Sep 2023 00:00:00 GMT", "description": "Results of hemoglobin gene KaKs (dN/dS) analyses in notothenioids in the research article \u201cCold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\u201d by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "locations": "Sub-Antarctic; Antarctica", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Rates of hemoglobin evolution among genes and across notothenioid species.", "uid": "601729", "west": -180.0}, {"awards": "2232891 Postlethwait, John; 1947040 Postlethwait, John; 1543383 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Thu, 24 Aug 2023 00:00:00 GMT", "description": "All input and output files of the phylogenetic trees of hemoglobin proteins in Notothenioids from the study \"Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\" by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, and John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "locations": "Sub-Antarctic; Antarctica", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Phylogenetic trees of hemoglobin proteins in notothenioids from the study \"Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\"", "uid": "601722", "west": -180.0}, {"awards": "2232891 Postlethwait, John; 1947040 Postlethwait, John; 1543383 Postlethwait, John", "bounds_geometry": ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"], "date_created": "Thu, 24 Aug 2023 00:00:00 GMT", "description": "Phylogenetic tree of 36 notothenioid species and five outgroup used throughout the study \"Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\" by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "locations": "Sub-Antarctic; Antarctica", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Postlethwait, John", "project_titles": "Evolution of hemoglobin genes in notothenioid fishes", "projects": [{"proj_uid": "p0010417", "repository": "USAP-DC", "title": "Evolution of hemoglobin genes in notothenioid fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Notothenioid species tree used in the study \"Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes\"", "uid": "601721", "west": -180.0}, {"awards": "0003956 Burns, Jennifer; 0523338 Burns, Jennifer", "bounds_geometry": ["POLYGON((-70 -65,-69.5 -65,-69 -65,-68.5 -65,-68 -65,-67.5 -65,-67 -65,-66.5 -65,-66 -65,-65.5 -65,-65 -65,-65 -65.5,-65 -66,-65 -66.5,-65 -67,-65 -67.5,-65 -68,-65 -68.5,-65 -69,-65 -69.5,-65 -70,-65.5 -70,-66 -70,-66.5 -70,-67 -70,-67.5 -70,-68 -70,-68.5 -70,-69 -70,-69.5 -70,-70 -70,-70 -69.5,-70 -69,-70 -68.5,-70 -68,-70 -67.5,-70 -67,-70 -66.5,-70 -66,-70 -65.5,-70 -65))"], "date_created": "Fri, 24 Jun 2022 00:00:00 GMT", "description": "Total body oxygen stores were determined for adult crabeater seals in the Marguerite Bay region of the Western Antarctic Peninsula. This study was conducted in 2001 and 2002 as part of the Southern Ocean GLOBEC collaboration.", "east": -65.0, "geometry": ["POINT(-67.5 -67.5)"], "keywords": "Antarctica; Crabeater Seal; GLOBEC; Hemoglobin; LMG0104; LMG0106; LMG0204; LMG0205; Marguerite Bay; Myoglobin; Oxygen Stores; Seals", "locations": "Antarctica; Marguerite Bay", "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Burns, Jennifer", "project_titles": "Foraging Ecology of Crabeater Seals (Lobodon Carcinophagus)", "projects": [{"proj_uid": "p0010345", "repository": "USAP-DC", "title": "Foraging Ecology of Crabeater Seals (Lobodon Carcinophagus)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Crabeater seal oxygen stores", "uid": "601583", "west": -70.0}, {"awards": "1341663 O\u0027Brien, Kristin; 1341602 Crockett, Elizabeth", "bounds_geometry": null, "date_created": "Thu, 24 Dec 2020 00:00:00 GMT", "description": "Antarctic notothenioids are noted for extreme stenothermy, yet underpinnings of their thermal limits are not fully understood. We hypothesized that properties of ventricular membranes could explain previously observed differences among notothenioids in temperature onset of cardiac arrhythmias and persistent asystole. Microsomes were prepared using ventricles from six species of notothenioids, including four species from the hemoglobin-less (Hb-) family Channichthyidae (icefishes), which also differentially express cardiac myoglobin (Mb), and two species from the (Hb+) Nototheniidae. We determined membrane fluidity and structural integrity by quantifying fluorescence depolarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and leakage of 5(6)-carboxyfluorescein, respectively, over a temperature range from ambient (0 \u00b0C) to 20 \u00b0C. Compositions of membrane phospholipids and cholesterol contents were also quantified. Membranes from all four species of icefishes exhibited greater fluidity than membranes from the red-blooded species N. coriiceps. Thermal sensitivity of fluidity did not vary among species. The greatest thermal sensitivity to leakage occurred between 0 and 5 \u00b0C for all species, while membranes from the icefish, Chaenocephalus aceratus (Hb-/Mb-) displayed leakage that was nearly 1.5-fold greater than leakage in N. coriiceps (Hb+/Mb+). Contents of phosphatidylethanolamine (PE) were approximately 1.5-fold greater in icefishes than in red-blooded fishes, and phospholipids had a higher degree of unsaturation in icefishes than in Hb + notothenioids. Cholesterol contents were lowest in Champsocephalus gunnari (Hb-/Mb-) and highest in the two Hb+/Mb + species, G. gibberifrons and N. coriiceps. Our results reveal marked differences in membrane properties and indicate a breach in membrane fluidity and structural integrity at a lower temperature in icefishes than in red-blooded notothenioids. ", "east": null, "geometry": null, "keywords": "Antarctica; Antarctic Peninsula", "locations": "Antarctica; Antarctic Peninsula", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "O\u0027Brien, Kristin; Evans, Elizabeth; Farnoud, Amir; Crockett, Elizabeth", "project_titles": "Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes", "projects": [{"proj_uid": "p0010084", "repository": "USAP-DC", "title": "Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Thermal sensitivity of membrane fluidity and integrity in hearts of Antarctic fishes that vary in expression of hemoglobin and myoglobin", "uid": "601414", "west": null}, {"awards": "1341602 Crockett, Elizabeth; 1341663 O\u0027Brien, Kristin", "bounds_geometry": null, "date_created": "Fri, 18 Dec 2020 00:00:00 GMT", "description": "The ability of Antarctic notothenioid fishes to mount a robust molecular response to hypoxia is largely unknown. The transcription factor, hypoxia-inducible factor-1 (HIF-1), a heterodimer of HIF-1\u03b1 and HIF-1\u03b2 subunits, is the master regulator of oxygen homeostasis in most metazoans. We sought to determine if, in the hearts of Antarctic notothenioids, HIF-1 is activated and functional in response to either an acute heat stress or hypoxia. The red-blooded Notothenia coriiceps and the hemoglobinless icefish, Chaenocephalus aceratus, were exposed to their critical thermal maximum (CTMAX) or hypoxia (5.0 \u00b1 0.3 mg of O2 L-1) for 2 h. Additionally, N. coriiceps was exposed to 2.3 \u00b1 0.3 mg of O2 L-1 for 12 h, and red-blooded Gobionotothen gibberifrons was exposed to both levels of hypoxia. Levels of HIF-1\u03b1 were quantified in nuclei isolated from heart ventricles using western blotting. Transcript levels of genes involved in anaerobic metabolism, and known to be regulated by HIF-1, were quantified by real-time PCR, and lactate levels were measured in heart ventricles. Protein levels of HIF-1\u03b1 increase in nuclei of hearts of N. coriiceps and C. aceratus in response to exposure to CTMAX and in hearts of N. coriiceps exposed to severe hypoxia, yet mRNA levels of anaerobic metabolic genes do not increase in any species, nor do lactate levels increase, suggesting that HIF-1 does not stimulate metabolic remodeling in hearts of notothenioids under these conditions. Together, these data suggest that Antarctic notothenioids may be vulnerable to hypoxic events, which are likely to increase with climate warming. ", "east": null, "geometry": null, "keywords": "Antarctica; Antarctic Peninsula", "locations": "Antarctica; Antarctic Peninsula", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "O\u0027Brien, Kristin", "project_titles": "Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes", "projects": [{"proj_uid": "p0010084", "repository": "USAP-DC", "title": "Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Hypoxia response of hearts of Antarctic fishes", "uid": "601406", "west": null}, {"awards": "0741301 O\u0027Brien, Kristin", "bounds_geometry": ["POLYGON((-64.45 -63.29,-64.249 -63.29,-64.048 -63.29,-63.847 -63.29,-63.646 -63.29,-63.445 -63.29,-63.244 -63.29,-63.043 -63.29,-62.842 -63.29,-62.641 -63.29,-62.44 -63.29,-62.44 -63.371,-62.44 -63.452,-62.44 -63.533,-62.44 -63.614,-62.44 -63.695,-62.44 -63.776,-62.44 -63.857,-62.44 -63.938,-62.44 -64.019,-62.44 -64.1,-62.641 -64.1,-62.842 -64.1,-63.043 -64.1,-63.244 -64.1,-63.445 -64.1,-63.646 -64.1,-63.847 -64.1,-64.048 -64.1,-64.249 -64.1,-64.45 -64.1,-64.45 -64.019,-64.45 -63.938,-64.45 -63.857,-64.45 -63.776,-64.45 -63.695,-64.45 -63.614,-64.45 -63.533,-64.45 -63.452,-64.45 -63.371,-64.45 -63.29))"], "date_created": "Tue, 01 Jan 2013 00:00:00 GMT", "description": "Antarctic notothenioid fishes have evolved in the Southern Ocean for 10-14 MY under an unusual set of circumstances. Their characteristics include the complete absence of the circulating oxygen-binding protein, hemoglobin (Hb) within the Channichthyid (Icefish) family of notothenioids. Moreover, some species within the 16 members of this family have also lost the ability to express the oxygen-binding and storage protein, myoglobin (Mb) in cardiac muscle. Our previous work has determined that the loss of Hb and/or Mb is correlated with significant increases in densities of mitochondria within oxidative tissues, and extensive remodeling of these vital organelles. To date, nothing is known about how modifications in mitochondrial architecture of icefishes affect organelle function, or more importantly, how they affect organismal-level physiology. Most critical for Antarctic fishes is that mitochondrial characteristics have been linked to how well ectotherms can withstand increases in temperature. \nThis collaborative research project will address the hypothesis that the unusual mitochondrial architecture of Antarctic Channichthyids has led to changes in function that impact their ability to withstand elevations in temperature. Specifically, the research will (1) determine if the unusual mitochondrial architecture of icefishes affects function and contributes to organismal thermal sensitivity, (2) identify differences in organismal thermal tolerance between red- and white- blooded notothenioids, (3) identify molecular mechanisms regulating changes in mitochondrial structure in icefishes. The results may establish channichthyid icefishes as a sentinel taxon for signaling the impact of global warming on the Southern Ocean. Broad impacts of this project will be realized by participation of high school biology teachers in field work through cooperation with the ARMADA project at the University of Rhode Island, as well as graduate education.\n", "east": -62.44, "geometry": ["POINT(-63.445 -63.695)"], "keywords": "Biota; Oceans; Pot; Southern Ocean; Trawl", "locations": "Southern Ocean", "north": -63.29, "nsf_funding_programs": null, "persons": "O\u0027Brien, Kristin", "project_titles": "Collaborative Research: Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes", "projects": [{"proj_uid": "p0000483", "repository": "USAP-DC", "title": "Collaborative Research: Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.1, "title": "Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes", "uid": "600084", "west": -64.45}, {"awards": "0437887 Sidell, Bruce", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "The polar ocean presently surrounding Antarctica is the coldest, most thermally stable marine environment on earth. Because oxygen solubility in seawater is inversely proportional to temperature, the cold Antarctic seas are an exceptionally oxygen-rich aquatic habitat. Eight families of a single perciform suborder, the Notothenioidei, dominate the present fish fauna surrounding Antarctica. Notothenioids account for approximately 35% of fish species and 90% of fish biomass south of the Antarctic Polar Front. Radiation of closely related notothenioid species thus has occurred rapidly and under a very unusual set of conditions: relative oceanographic isolation from other faunas due to circumpolar currents and deep ocean trenches surrounding the continent, chronically, severely cold water temperatures, very high oxygen availability, very low levels of niche competition in a Southern Ocean depauperate of species subsequent to a dramatic crash in species diversity of fishes that occurred sometime between the mid-Tertiary and present. These features make Antarctic notothenioid fishes an uniquely attractive group for the study of physiological and biochemical adaptations to cold body temperature. Few distinctive features of Antarctic fishes are as unique as the pattern of expression of oxygen-binding proteins in one notothenioid family, the Channichthyidae (Antarctic icefishes). All channichthyid icefishes lack the circulating oxygen-binding protein, hemoglobin (Hb); the intracellular oxygen-binding protein, myoglobin (Mb) is not uniformly expressed in species of this family. Both proteins are normally considered essential for adequate delivery of oxygen to aerobically poised tissues of animals. To compensate for the absence of Hb, icefishes have developed large hearts, rapidly circulate a large blood volume and possess elaborate vasculature of larger lumenal diameter than is seen in red-blooded fishes. Loss of Mb expression in oxidative muscles correlates with dramatic elevation in density of mitochondria within the cell, although each individual organelle is less densely packed with respiratory proteins. Within the framework of oxygen movement, the adaptive significance of greater vascular density and mitochondrial populations is understandable but mechanisms underlying development of these characteristics remain unknown. The answer may lie in another major function of both Hb and Mb, degradation of the ubiquitous bioactive compound, nitric oxide (NO). The research will test the hypothesis that loss of hemoprotein expression in icefishes has resulted in an increase in levels of NO that mediate modification of vascular systems and expansion of mitochondrial populations in oxidative tissues. The objectives of the proposal are to quantify the vascular density of retinas in +Hb and -Hb notothenioid species, to characterize NOS isoforms and catalytic activity in retina and cardiac muscle of Antarctic notothenioid fishes, to evaluate level of expression of downstream factors implicat ed in angiogenesis (in retinal tissue) and mitochondrial biogenesis (in cardiac muscle), and to determine whether inhibition of NOS in vivo results in regression of angiogenic and mitochondrial biogenic responses in icefishes. Broader impacts range from basic biology, through training of young scientists, to enhanced understanding of clinically relevant biomedical processes.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Biota; Oceans; Pot; Sample/collection Description; Sample/Collection Description; Southern Ocean; Trawl", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Sidell, Bruce", "project_titles": "Collaborative Research: Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis.", "projects": [{"proj_uid": "p0000527", "repository": "USAP-DC", "title": "Collaborative Research: Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis", "uid": "600039", "west": -180.0}, {"awards": "0538594 Ponganis, Paul", "bounds_geometry": ["POLYGON((165.983 -77.683,166.0164 -77.683,166.0498 -77.683,166.0832 -77.683,166.1166 -77.683,166.15 -77.683,166.1834 -77.683,166.2168 -77.683,166.2502 -77.683,166.2836 -77.683,166.317 -77.683,166.317 -77.6897,166.317 -77.6964,166.317 -77.7031,166.317 -77.7098,166.317 -77.7165,166.317 -77.7232,166.317 -77.7299,166.317 -77.7366,166.317 -77.7433,166.317 -77.75,166.2836 -77.75,166.2502 -77.75,166.2168 -77.75,166.1834 -77.75,166.15 -77.75,166.1166 -77.75,166.0832 -77.75,166.0498 -77.75,166.0164 -77.75,165.983 -77.75,165.983 -77.7433,165.983 -77.7366,165.983 -77.7299,165.983 -77.7232,165.983 -77.7165,165.983 -77.7098,165.983 -77.7031,165.983 -77.6964,165.983 -77.6897,165.983 -77.683))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "The research will examine blood and muscle oxygen store depletion in relation to the documented aerobic dive limit (ADL, onset of post-dive blood lactate accumulation) in diving of emperor penguins. The intellectual merits of this proposal involve its evaluation of the physiological basis of the ADL concept. The ADL is probably the most commonly-used, but rarely measured, factor to interpret and model the behavior and foraging ecology of diving animals. Based on prior studies, and on recent investigations of respiratory and blood oxygen depletion during dives of emperor penguins, it is hypothesized that the ADL is a result of the depletion of myoglobin (Mb)-bound oxygen and increased glycolysis in the primary locomotory muscles. This project will accurately define the physiological mechanisms underlying the ADL through 1) evaluation of the rate and magnitude of muscle oxygen depletion during dives in relation to the previously measured ADL, 2) characterization of the hemoglobin-oxygen dissociation curve in blood of emperor penguins and comparison of that curve to those of other diving and non-diving species, 3) application of the emperor hemoglogin-oxygen dissociation curve to previously collected oxygen and hemoglobin data in order to estimate the rate and magnitude of blood oxygen depletion during dives, and 4) measurement of muscle phosphoocreatine and glycogen concentrations in order to estimate their potential contributions to muscle energy metabolism during diving. The project also continues the census and monitoring of the emperor colonies in the Ross Sea, which is especially important in light of both fisheries activity and the movement of iceberg B15-A. Broader impacts of the project include: 1) technological development of microprocessor-based, \u0027backpack\u0027 near-infrared spectrophotometer, which will be applicable not only to other species, but also to other fields (i.e., exercise physiology), 2) collaboration with the Department of Anesthesia at the U.S. Naval Hospital in San Diego in the training of anesthesia residents in research techniques, 3) the training and thesis research of two graduate students in these techniques and in Antarctic field research, and 4) a better understanding of the ADL concept and its use in the fields of diving behavior and physiology. In addition the annual census of emperor penguin colonies in the Ross Sea, in conjunction with the continued evaluation of previously developed remote cameras to monitor colony status, will form the basis of a new educational web site, and allow development of an educational outreach program to school children through SeaWorld of San Diego.", "east": 166.317, "geometry": ["POINT(166.15 -77.7165)"], "keywords": "Antarctica; Biota; Oceans; Penguin; Southern Ocean", "locations": "Antarctica; Southern Ocean", "north": -77.683, "nsf_funding_programs": null, "persons": "Ponganis, Paul", "project_titles": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "projects": [{"proj_uid": "p0000535", "repository": "USAP-DC", "title": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.75, "title": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "uid": "600057", "west": 165.983}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.
|
2232891 1947040 1543383 |
2023-09-08 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Phylogenetic tree of Notothenioid species used in analyses and results of the HyPhy aBSREL tests for diversifying selection in notothenioid hemoglobin genes in the research article “Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes” by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
Notothenioid hemoglobin protein 3D modeling.
|
1543383 1947040 2232891 |
2023-09-08 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Notothenioid hemoglobin protein 3D modeling using SWISS-MODEL in the research article “Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes” by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.
|
1543383 1947040 2232891 |
2023-09-08 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Phylogenetic tree of Notothenioid species used in analyses and results of the HyPhy RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in the research article “Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes” by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.
|
2232891 1543383 1947040 |
2023-09-08 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Phylogenetic tree of Notothenioid species used in analyses and results of the HyPhy MEME tests for sites evolving under episodic diversifying selection in notothenioid hemoglobin genes in the research article “Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes” by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
Rates of hemoglobin evolution among genes and across notothenioid species.
|
2232891 1543383 1947040 |
2023-09-08 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Results of hemoglobin gene KaKs (dN/dS) analyses in notothenioids in the research article “Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes” by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
Phylogenetic trees of hemoglobin proteins in notothenioids from the study "Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes"
|
2232891 1947040 1543383 |
2023-08-24 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
All input and output files of the phylogenetic trees of hemoglobin proteins in Notothenioids from the study "Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes" by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, and John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
Notothenioid species tree used in the study "Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes"
|
2232891 1947040 1543383 |
2023-08-24 | Desvignes, Thomas; Postlethwait, John |
Evolution of hemoglobin genes in notothenioid fishes |
Phylogenetic tree of 36 notothenioid species and five outgroup used throughout the study "Cold-driven hemoglobin evolution in Antarctic notothenioid fishes prior to hemoglobin gene loss in white-blooded icefishes" by Thomas Desvignes, Iliana Bista, Karina Herrera, Audrey Landes, John H. Postlethwait. | ["POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))"] | ["POINT(0 -89.999)"] | false | false |
Crabeater seal oxygen stores
|
0003956 0523338 |
2022-06-24 | Burns, Jennifer |
Foraging Ecology of Crabeater Seals (Lobodon Carcinophagus) |
Total body oxygen stores were determined for adult crabeater seals in the Marguerite Bay region of the Western Antarctic Peninsula. This study was conducted in 2001 and 2002 as part of the Southern Ocean GLOBEC collaboration. | ["POLYGON((-70 -65,-69.5 -65,-69 -65,-68.5 -65,-68 -65,-67.5 -65,-67 -65,-66.5 -65,-66 -65,-65.5 -65,-65 -65,-65 -65.5,-65 -66,-65 -66.5,-65 -67,-65 -67.5,-65 -68,-65 -68.5,-65 -69,-65 -69.5,-65 -70,-65.5 -70,-66 -70,-66.5 -70,-67 -70,-67.5 -70,-68 -70,-68.5 -70,-69 -70,-69.5 -70,-70 -70,-70 -69.5,-70 -69,-70 -68.5,-70 -68,-70 -67.5,-70 -67,-70 -66.5,-70 -66,-70 -65.5,-70 -65))"] | ["POINT(-67.5 -67.5)"] | false | false |
Thermal sensitivity of membrane fluidity and integrity in hearts of Antarctic fishes that vary in expression of hemoglobin and myoglobin
|
1341663 1341602 |
2020-12-24 | O'Brien, Kristin; Evans, Elizabeth; Farnoud, Amir; Crockett, Elizabeth |
Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes |
Antarctic notothenioids are noted for extreme stenothermy, yet underpinnings of their thermal limits are not fully understood. We hypothesized that properties of ventricular membranes could explain previously observed differences among notothenioids in temperature onset of cardiac arrhythmias and persistent asystole. Microsomes were prepared using ventricles from six species of notothenioids, including four species from the hemoglobin-less (Hb-) family Channichthyidae (icefishes), which also differentially express cardiac myoglobin (Mb), and two species from the (Hb+) Nototheniidae. We determined membrane fluidity and structural integrity by quantifying fluorescence depolarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and leakage of 5(6)-carboxyfluorescein, respectively, over a temperature range from ambient (0 °C) to 20 °C. Compositions of membrane phospholipids and cholesterol contents were also quantified. Membranes from all four species of icefishes exhibited greater fluidity than membranes from the red-blooded species N. coriiceps. Thermal sensitivity of fluidity did not vary among species. The greatest thermal sensitivity to leakage occurred between 0 and 5 °C for all species, while membranes from the icefish, Chaenocephalus aceratus (Hb-/Mb-) displayed leakage that was nearly 1.5-fold greater than leakage in N. coriiceps (Hb+/Mb+). Contents of phosphatidylethanolamine (PE) were approximately 1.5-fold greater in icefishes than in red-blooded fishes, and phospholipids had a higher degree of unsaturation in icefishes than in Hb + notothenioids. Cholesterol contents were lowest in Champsocephalus gunnari (Hb-/Mb-) and highest in the two Hb+/Mb + species, G. gibberifrons and N. coriiceps. Our results reveal marked differences in membrane properties and indicate a breach in membrane fluidity and structural integrity at a lower temperature in icefishes than in red-blooded notothenioids. | [] | [] | false | false |
Hypoxia response of hearts of Antarctic fishes
|
1341602 1341663 |
2020-12-18 | O'Brien, Kristin |
Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes |
The ability of Antarctic notothenioid fishes to mount a robust molecular response to hypoxia is largely unknown. The transcription factor, hypoxia-inducible factor-1 (HIF-1), a heterodimer of HIF-1α and HIF-1β subunits, is the master regulator of oxygen homeostasis in most metazoans. We sought to determine if, in the hearts of Antarctic notothenioids, HIF-1 is activated and functional in response to either an acute heat stress or hypoxia. The red-blooded Notothenia coriiceps and the hemoglobinless icefish, Chaenocephalus aceratus, were exposed to their critical thermal maximum (CTMAX) or hypoxia (5.0 ± 0.3 mg of O2 L-1) for 2 h. Additionally, N. coriiceps was exposed to 2.3 ± 0.3 mg of O2 L-1 for 12 h, and red-blooded Gobionotothen gibberifrons was exposed to both levels of hypoxia. Levels of HIF-1α were quantified in nuclei isolated from heart ventricles using western blotting. Transcript levels of genes involved in anaerobic metabolism, and known to be regulated by HIF-1, were quantified by real-time PCR, and lactate levels were measured in heart ventricles. Protein levels of HIF-1α increase in nuclei of hearts of N. coriiceps and C. aceratus in response to exposure to CTMAX and in hearts of N. coriiceps exposed to severe hypoxia, yet mRNA levels of anaerobic metabolic genes do not increase in any species, nor do lactate levels increase, suggesting that HIF-1 does not stimulate metabolic remodeling in hearts of notothenioids under these conditions. Together, these data suggest that Antarctic notothenioids may be vulnerable to hypoxic events, which are likely to increase with climate warming. | [] | [] | false | false |
Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes
|
0741301 |
2013-01-01 | O'Brien, Kristin |
Collaborative Research: Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes |
Antarctic notothenioid fishes have evolved in the Southern Ocean for 10-14 MY under an unusual set of circumstances. Their characteristics include the complete absence of the circulating oxygen-binding protein, hemoglobin (Hb) within the Channichthyid (Icefish) family of notothenioids. Moreover, some species within the 16 members of this family have also lost the ability to express the oxygen-binding and storage protein, myoglobin (Mb) in cardiac muscle. Our previous work has determined that the loss of Hb and/or Mb is correlated with significant increases in densities of mitochondria within oxidative tissues, and extensive remodeling of these vital organelles. To date, nothing is known about how modifications in mitochondrial architecture of icefishes affect organelle function, or more importantly, how they affect organismal-level physiology. Most critical for Antarctic fishes is that mitochondrial characteristics have been linked to how well ectotherms can withstand increases in temperature. This collaborative research project will address the hypothesis that the unusual mitochondrial architecture of Antarctic Channichthyids has led to changes in function that impact their ability to withstand elevations in temperature. Specifically, the research will (1) determine if the unusual mitochondrial architecture of icefishes affects function and contributes to organismal thermal sensitivity, (2) identify differences in organismal thermal tolerance between red- and white- blooded notothenioids, (3) identify molecular mechanisms regulating changes in mitochondrial structure in icefishes. The results may establish channichthyid icefishes as a sentinel taxon for signaling the impact of global warming on the Southern Ocean. Broad impacts of this project will be realized by participation of high school biology teachers in field work through cooperation with the ARMADA project at the University of Rhode Island, as well as graduate education. | ["POLYGON((-64.45 -63.29,-64.249 -63.29,-64.048 -63.29,-63.847 -63.29,-63.646 -63.29,-63.445 -63.29,-63.244 -63.29,-63.043 -63.29,-62.842 -63.29,-62.641 -63.29,-62.44 -63.29,-62.44 -63.371,-62.44 -63.452,-62.44 -63.533,-62.44 -63.614,-62.44 -63.695,-62.44 -63.776,-62.44 -63.857,-62.44 -63.938,-62.44 -64.019,-62.44 -64.1,-62.641 -64.1,-62.842 -64.1,-63.043 -64.1,-63.244 -64.1,-63.445 -64.1,-63.646 -64.1,-63.847 -64.1,-64.048 -64.1,-64.249 -64.1,-64.45 -64.1,-64.45 -64.019,-64.45 -63.938,-64.45 -63.857,-64.45 -63.776,-64.45 -63.695,-64.45 -63.614,-64.45 -63.533,-64.45 -63.452,-64.45 -63.371,-64.45 -63.29))"] | ["POINT(-63.445 -63.695)"] | false | false |
Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis
|
0437887 |
2009-01-01 | Sidell, Bruce |
Collaborative Research: Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis. |
The polar ocean presently surrounding Antarctica is the coldest, most thermally stable marine environment on earth. Because oxygen solubility in seawater is inversely proportional to temperature, the cold Antarctic seas are an exceptionally oxygen-rich aquatic habitat. Eight families of a single perciform suborder, the Notothenioidei, dominate the present fish fauna surrounding Antarctica. Notothenioids account for approximately 35% of fish species and 90% of fish biomass south of the Antarctic Polar Front. Radiation of closely related notothenioid species thus has occurred rapidly and under a very unusual set of conditions: relative oceanographic isolation from other faunas due to circumpolar currents and deep ocean trenches surrounding the continent, chronically, severely cold water temperatures, very high oxygen availability, very low levels of niche competition in a Southern Ocean depauperate of species subsequent to a dramatic crash in species diversity of fishes that occurred sometime between the mid-Tertiary and present. These features make Antarctic notothenioid fishes an uniquely attractive group for the study of physiological and biochemical adaptations to cold body temperature. Few distinctive features of Antarctic fishes are as unique as the pattern of expression of oxygen-binding proteins in one notothenioid family, the Channichthyidae (Antarctic icefishes). All channichthyid icefishes lack the circulating oxygen-binding protein, hemoglobin (Hb); the intracellular oxygen-binding protein, myoglobin (Mb) is not uniformly expressed in species of this family. Both proteins are normally considered essential for adequate delivery of oxygen to aerobically poised tissues of animals. To compensate for the absence of Hb, icefishes have developed large hearts, rapidly circulate a large blood volume and possess elaborate vasculature of larger lumenal diameter than is seen in red-blooded fishes. Loss of Mb expression in oxidative muscles correlates with dramatic elevation in density of mitochondria within the cell, although each individual organelle is less densely packed with respiratory proteins. Within the framework of oxygen movement, the adaptive significance of greater vascular density and mitochondrial populations is understandable but mechanisms underlying development of these characteristics remain unknown. The answer may lie in another major function of both Hb and Mb, degradation of the ubiquitous bioactive compound, nitric oxide (NO). The research will test the hypothesis that loss of hemoprotein expression in icefishes has resulted in an increase in levels of NO that mediate modification of vascular systems and expansion of mitochondrial populations in oxidative tissues. The objectives of the proposal are to quantify the vascular density of retinas in +Hb and -Hb notothenioid species, to characterize NOS isoforms and catalytic activity in retina and cardiac muscle of Antarctic notothenioid fishes, to evaluate level of expression of downstream factors implicat ed in angiogenesis (in retinal tissue) and mitochondrial biogenesis (in cardiac muscle), and to determine whether inhibition of NOS in vivo results in regression of angiogenic and mitochondrial biogenic responses in icefishes. Broader impacts range from basic biology, through training of young scientists, to enhanced understanding of clinically relevant biomedical processes. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins
|
0538594 |
2009-01-01 | Ponganis, Paul |
The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins |
The research will examine blood and muscle oxygen store depletion in relation to the documented aerobic dive limit (ADL, onset of post-dive blood lactate accumulation) in diving of emperor penguins. The intellectual merits of this proposal involve its evaluation of the physiological basis of the ADL concept. The ADL is probably the most commonly-used, but rarely measured, factor to interpret and model the behavior and foraging ecology of diving animals. Based on prior studies, and on recent investigations of respiratory and blood oxygen depletion during dives of emperor penguins, it is hypothesized that the ADL is a result of the depletion of myoglobin (Mb)-bound oxygen and increased glycolysis in the primary locomotory muscles. This project will accurately define the physiological mechanisms underlying the ADL through 1) evaluation of the rate and magnitude of muscle oxygen depletion during dives in relation to the previously measured ADL, 2) characterization of the hemoglobin-oxygen dissociation curve in blood of emperor penguins and comparison of that curve to those of other diving and non-diving species, 3) application of the emperor hemoglogin-oxygen dissociation curve to previously collected oxygen and hemoglobin data in order to estimate the rate and magnitude of blood oxygen depletion during dives, and 4) measurement of muscle phosphoocreatine and glycogen concentrations in order to estimate their potential contributions to muscle energy metabolism during diving. The project also continues the census and monitoring of the emperor colonies in the Ross Sea, which is especially important in light of both fisheries activity and the movement of iceberg B15-A. Broader impacts of the project include: 1) technological development of microprocessor-based, 'backpack' near-infrared spectrophotometer, which will be applicable not only to other species, but also to other fields (i.e., exercise physiology), 2) collaboration with the Department of Anesthesia at the U.S. Naval Hospital in San Diego in the training of anesthesia residents in research techniques, 3) the training and thesis research of two graduate students in these techniques and in Antarctic field research, and 4) a better understanding of the ADL concept and its use in the fields of diving behavior and physiology. In addition the annual census of emperor penguin colonies in the Ross Sea, in conjunction with the continued evaluation of previously developed remote cameras to monitor colony status, will form the basis of a new educational web site, and allow development of an educational outreach program to school children through SeaWorld of San Diego. | ["POLYGON((165.983 -77.683,166.0164 -77.683,166.0498 -77.683,166.0832 -77.683,166.1166 -77.683,166.15 -77.683,166.1834 -77.683,166.2168 -77.683,166.2502 -77.683,166.2836 -77.683,166.317 -77.683,166.317 -77.6897,166.317 -77.6964,166.317 -77.7031,166.317 -77.7098,166.317 -77.7165,166.317 -77.7232,166.317 -77.7299,166.317 -77.7366,166.317 -77.7433,166.317 -77.75,166.2836 -77.75,166.2502 -77.75,166.2168 -77.75,166.1834 -77.75,166.15 -77.75,166.1166 -77.75,166.0832 -77.75,166.0498 -77.75,166.0164 -77.75,165.983 -77.75,165.983 -77.7433,165.983 -77.7366,165.983 -77.7299,165.983 -77.7232,165.983 -77.7165,165.983 -77.7098,165.983 -77.7031,165.983 -77.6964,165.983 -77.6897,165.983 -77.683))"] | ["POINT(166.15 -77.7165)"] | false | false |