{"dp_type": "Project", "free_text": "Hemoglobin"}
[{"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))", "dataset_titles": "aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.; MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.; Notothenioid hemoglobin protein 3D modeling.; Notothenioid species tree used in the study.; Phylogenetic trees of hemoglobin proteins in notothenioids.; Rates of hemoglobin evolution among genes and across notothenioid species.; RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.", "datasets": [{"dataset_uid": "601732", "doi": "10.15784/601732", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Notothenioid hemoglobin protein 3D modeling.", "url": "https://www.usap-dc.org/view/dataset/601732"}, {"dataset_uid": "601721", "doi": "10.15784/601721", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Notothenioid species tree used in the study.", "url": "https://www.usap-dc.org/view/dataset/601721"}, {"dataset_uid": "601722", "doi": "10.15784/601722", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic trees of hemoglobin proteins in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601722"}, {"dataset_uid": "601728", "doi": "10.15784/601728", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601728"}, {"dataset_uid": "601729", "doi": "10.15784/601729", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Rates of hemoglobin evolution among genes and across notothenioid species.", "url": "https://www.usap-dc.org/view/dataset/601729"}, {"dataset_uid": "601730", "doi": "10.15784/601730", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.", "url": "https://www.usap-dc.org/view/dataset/601730"}, {"dataset_uid": "601731", "doi": "10.15784/601731", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601731"}], "date_created": "Wed, 03 May 2023 00:00:00 GMT", "description": "Antarctic notothenioid fishes, also known as cryonotothenioids, inhabit the icy and highly oxygenated waters surrounding the Antarctic continent after diverging from notothenioids inhabiting more temperate waters. Notothenioid hemoglobin and blood parameters are known to have evolved along with the establishment of stable polar conditions, and among Antarctic notothenioids, icefishes are evolutionary oddities living without hemoglobin following the deletion of all functional hemoglobin genes from their genomes. In this project, we investigate the evolution of hemoglobin genes and gene clusters across the notothenioid radiation until their loss in the icefish ancestor after its divergence from the dragonfish lineage to understand the forces, mechanisms, and potential causes for hemoglobin gene loss in the icefish ancestor.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "FISH; Icefish; Cryonotothenioid; Gene; Plunderfish; Eleginopsioidea; AQUATIC ECOSYSTEMS; Dragonfish; Sub-Antarctic; Notothenioid; Blood; Hemoglobin", "locations": "Sub-Antarctic", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Desvignes, Thomas; Postlethwait, John", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Evolution of hemoglobin genes in notothenioid fishes", "uid": "p0010417", "west": -180.0}, {"awards": "1645087 Catchen, Julian", "bounds_geometry": null, "dataset_titles": "Chromosome-Level Genome Assembly and Circadian Gene Repertoire of the Patagonia Blennie Eleginops maclovinus\u2014The Closest Ancestral Proxy of Antarctic Cryonotothenioids; Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki; Genomics of Secondarily Temperate Adaptation in the Only Non-Antarctic Icefish", "datasets": [{"dataset_uid": "200331", "doi": "10.5061/dryad.ghx3ffbs3", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki", "url": "https://datadryad.org/stash/dataset/doi:10.5061/dryad.ghx3ffbs3"}, {"dataset_uid": "200381", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Chromosome-Level Genome Assembly and Circadian Gene Repertoire of the Patagonia Blennie Eleginops maclovinus\u2014The Closest Ancestral Proxy of Antarctic Cryonotothenioids", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA917608"}, {"dataset_uid": "200330", "doi": "", "keywords": null, "people": null, "repository": "NCBI ", "science_program": null, "title": "Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA861284"}, {"dataset_uid": "200380", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Genomics of Secondarily Temperate Adaptation in the Only Non-Antarctic Icefish", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857989"}], "date_created": "Mon, 10 Oct 2022 00:00:00 GMT", "description": "As plate tectonics pushed Antarctica into a polar position, by ~34 million years ago, the continent and its surrounding Southern Ocean (SO) became geographically and thermally isolated by the Antarctic Circumpolar Current. Terrestrial and marine glaciation followed, resulting in extinctions as well as the survival and radiation of unique flora and fauna. The notothenioid fish survived and arose from a common ancestral stock into tax with 120 species that dominates today?s SO fish fauna. The Notothenioids evolved adaptive traits including novel antifreeze proteins for survival in extreme cold, but also suffered seemingly adverse trait loss including red blood cells in the icefish family, and the ability to mount cellular responses to mitigate heat stress ? otherwise ubiquitous across all life. This project aims to understand how the notothenoid genomes have changed and contributed to their evolution in the cold. The project will sequence, analyze and compare the genomes of two strategic pairs of notothenioid fishes representing both red-blooded and white-blooded species. Each pair will consist of one Antarctic species and one that has readapted to the temperate waters of S. America or New Zealand. The project will also compare the Antarctic species genomes to a genome of the closet non-Antarctic relative representing the temperate notothenioid ancestor. The work aims to uncover the mechanisms that enabled the adaptive evolution of this ecologically vital group of fish in the freezing Southern Ocean, and shed light on their adaptability to a warming world. The finished genomes will be made available to promote and advance Antarctic research and the project will host a symposium of Polar researchers to discuss the cutting edge developments regarding of genomic adaptations in the polar region. Despite subzero, icy conditions that are perilous to teleost fish, the fish fauna of the isolated Southern Ocean (SO) surrounding Antarctica is remarkably bountiful. A single teleost group ? the notothenioid fishes ? dominate the fauna, comprising over 120 species that arose from a common ancestor. When Antarctica became isolated and SO temperatures began to plunge in early Oligocene, the prior temperate fishes became extinct. The ancestor of Antarctic notothenioids overcame forbidding polar conditions and, absent niche competition, it diversified and filled the SO. How did notothenioids adapt to freezing environmental selection pressures and achieve such extraordinary success? And having specialized to life in chronic cold for 30 myr, can they evolve in pace with today?s warming climate to stay viable? Past studies of Antarctic notothenioid evolutionary adaptation have discovered various remarkable traits including the key, life-saving antifreeze proteins. But life specialized to cold also led to paradoxical trait changes such as the loss of the otherwise universal heat shock response, and of the O2-transporting hemoglobin and red blood cells in the icefish family. A few species interestingly regained abilities to live in temperate waters following the escape of their ancestor out of the freezing SO. This proposed project is the first major effort to advance the field from single trait studies to understanding the full spectrum of genomic and genetic responses to climatic and environmental change during notothenioid evolution, and to evaluate their adaptability to continuing climate change. To this end, the project will sequence the genomes of four key species that embody genomic responses to different thermal selection regimes during notothenioids? evolutionary history, and by comparative analyses of genomic structure, architecture and content, deduce the responding changes. Specifically, the project will (i) obtain whole genome assemblies of the red-blooded T. borchgrevinki and the S. American icefish C. esox; (ii) using the finished genomes from (i) as template, obtain assemblies of the New Zealand notothenioid N. angustata, and the white-blooded icefish C. gunnari, representing a long (11 myr) and recent (1 myr) secondarily temperate evolutionary history respectively. Genes that are under selection in the temperate environment but not in the Antarctic environment can be inferred to be directly necessary for that environment ? and the reverse is also true for genes under selection in the Antarctic but not in the temperate environment. Further, genes important for survival in temperate waters will show parallel selection between N. angustata and C. esox despite the fact that the two fish left the Antarctic at far separated time points. Finally, gene families that expanded due to strong selection within the cold Antarctic should show a degradation of duplicates in the temperate environment. The project will test these hypotheses using a number of techniques to compare the content and form of genes, the structure of the chromosomes containing those genes, and through the identification of key characters, such as selfish genetic elements, introns, and structural variants.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Genome Assembly; FISH; McMurdo Sound; Icefish; SHIPS; Notothenioid; Puerto Natales, Chile", "locations": "McMurdo Sound; Puerto Natales, Chile", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Catchen, Julian; Cheng, Chi-Hing", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "Dryad", "repositories": "Dryad; NCBI; NCBI ", "science_programs": null, "south": null, "title": "Evolutionary Genomic Responses in Antarctic Notothenioid Fishes", "uid": "p0010384", "west": null}, {"awards": "0003956 Burns, Jennifer; 9981683 Costa, Daniel", "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))", "dataset_titles": "Crabeater seal oxygen stores", "datasets": [{"dataset_uid": "601583", "doi": "10.15784/601583", "keywords": "Antarctica; Crabeater Seal; GLOBEC; Hemoglobin; LMG0104; LMG0106; LMG0204; LMG0205; Marguerite Bay; Myoglobin; Oxygen Stores; Seals", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Crabeater seal oxygen stores", "url": "https://www.usap-dc.org/view/dataset/601583"}], "date_created": "Wed, 29 Jun 2022 00:00:00 GMT", "description": "This collaborative study between the University of California, Santa Cruz, Duke University, the University of South Florida, the University of Alaska-Anchorage, and the University of California, San Diego will examine the identification of biological and physical features associated with the abundance and distribution of individual Antarctic predators; the identification and characterization of biological \u0027hot spots\u0027 within the Western Antarctic Peninsula; and the development of temporally and spatially explicit models of krill consumption within the WAP by vertebrate predators. It is one of several data synthesis and modeling components that use the data obtained in the course of the field work of the Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) experiment.\u003cbr/\u003eSO-Globec is a multidisciplinary effort focused on understanding the physical and biological factors that influence growth, reproduction, recruitment and survival of Antarctic krill (Euphausia superba). The program uses a multi-trophic level approach that includes the predators and competitors of Antarctic krill, represented by other zooplankton, fish, penguins, seals, and cetaceans. It is currently in a synthesis and modeling phase. This collaborative project is concerned with understanding how predators utilize \u0027hot spots\u0027, i.e. locally intense areas of biological productivity, and how \u0027hot spots\u0027 might temporally and spatially structure krill predation rates, and will be integrated with other synthesis and modeling studies that deal with the hydrography primary production, and krill dynamics.", "east": -65.0, "geometry": "POINT(-67.5 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "Marguerite Bay; MARINE ECOSYSTEMS", "locations": "Marguerite Bay", "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Burns, Jennifer; Costa, Daniel", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Foraging Ecology of Crabeater Seals (Lobodon Carcinophagus)", "uid": "p0010345", "west": -70.0}, {"awards": "1954241 O\u0027\u0027Brien, Kristin", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 17 Aug 2021 00:00:00 GMT", "description": "Part 1: Non-technical description: Global climate warming is increasing the frequency and severity of low oxygen events in marine and freshwater environments worldwide, and these events threaten the health of aquatic ecosystems and the viability of fish populations. The Southern Ocean surrounding Antarctica has historically been a stable, icy-cold, and oxygen-rich environment, but is now warming at an unprecedented rate and faster than all other regions in the Southern hemisphere. Antarctic fishes have evolved in sub-zero temperatures that have been stable over long periods of time with traits allowing them to thrive in frigid waters, but with diminished resilience to warming temperatures. Presently little is known about the ability of Antarctic fishes to withstand hypoxic, or low-oxygen, conditions that often accompany warming. This research will investigate the hypoxia tolerance of four species of Antarctic fishes, including two species of icefishes that lack the oxygen-carrying protein, hemoglobin, which may compromise their ability to oxygenate tissues under hypoxic conditions. The hypoxia tolerance of four Antarctic fish species will be compared to that of a related fish species inhabiting warmer coastal regions of South America. Physiological and biochemical responses to hypoxia will be evaluated and compared amongst the five species to bolster our predictions of the capacity of Antarctic fishes to cope with a changing environment. This research will provide training opportunities for undergraduate and graduate students, and a postdoctoral research fellow. A year-long seminar series hosted by the Aquarium of the Pacific will feature female scientists who work in Antarctica to inspire youth in the greater Los Angeles area to pursue careers in science. Part 2: Technical description: The overarching hypothesis to be tested in this project is that the long evolution of Antarctic notothenioid fishes in a cold, oxygen-rich environment has reduced their capacity to mount a robust physiological, biochemical, and molecular response to hypoxia compared to related, cold-temperate fish species. Hypoxia tolerance will be compared among the red-blooded Antarctic notothenioids, Notothenia coriiceps and Notothenia rossii; the hemoglobinless Antarctic icefishes, Chaenocephalus aceratus and Chionodraco rastrospinosus; and the basal, cold-temperate notothenioid, Eleginops maclovinus, a species that has never inhabited waters south of the Polar Front. The minimum level of oxygen required to sustain maintenance metabolic requirements (O2crit) will be quantified. Animals will then be exposed to 65% of O2crit for 48 hours, and responses to hypoxia will be evaluated by measuring hematocrit and hemoglobin levels, as well as metabolites in brain, liver, glycolytic and cardiac muscles. Maximal activities of key enzymes of aerobic and anaerobic metabolism will be quantified to assess capacities for synthesizing ATP in hypoxic conditions. Gill remodeling will be analyzed using light and scanning electron microscopy. The molecular response to hypoxia will be characterized in liver and brains by quantifying levels of the master transcriptional regulator of oxygen homeostasis, hypoxia-inducible factor-1 (HIF-1), and hypoxic gene expression will be quantified using RNA-Seq. Cell cultures will be used to determine if a previously identified insertion mutation in notothenioid HIF-1 affects the ability of HIF-1 to drive gene expression and thus, hypoxia tolerance. The results of this project will provide the most comprehensive assessment of the hypoxia tolerance of Antarctic fishes to date. Broader impacts include research training opportunities for undergraduate and graduate students and a postdoctoral research associate, with a focus on involving Native Alaskan students in research. In partnership with the Aquarium of the Pacific, a year-long public seminar series will be held, showcasing the research and careers of 9 women who conduct research in Antarctica. The goal of the series is to cultivate and empower a community of middle and high school students in the greater Los Angeles area to pursue their interests in science and related fields, and to enhance the public engagement capacities of research scientists so that they may better inspire youth and early career scientists in STEM fields. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; FIELD SURVEYS; USAP-DC; AMD; USA/NSF; Amd/Us; FISH", "locations": "Palmer Station", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "O\u0027Brien, Kristin", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "ANT LIA: Hypoxia Tolerance in Notothenioid Fishes", "uid": "p0010246", "west": null}, {"awards": "1341602 Crockett, Elizabeth; 1341663 O\u0027Brien, Kristin", "bounds_geometry": null, "dataset_titles": "Acclimation of cardiovascular function in Notothenia coriiceps; Adrenergic and adenosinergic regulation of the cardiovascular system in the Antarctic icefish Chaenocephalus aceratus; Cardiac metabolism in Antarctic fishes in response to an acute increase in temperature; Chaenocephalus aceratus HIF-1A mRNA, complete cds; Chionodraco rastrospinosus HIF-1A mRNA, partial cds; Effects of acute warming on cardiovascular performance of Antarctic fishes; Eleginops maclovinus HIF-1A mRNA, partial cds; Gymnodraco acuticeps HIF-1A mRNA, partial cds; Hypoxia response of hearts of Antarctic fishes; Maximum cardiac performance of Antarctic fishes that lack haemoglobin and myoglobin: exploring the effect of warming on nature\u2019s natural knockouts; Measurements of splenic contraction in Antarctic fishes; Mitochondrial membranes in cardiac muscle from Antarctic notothenioid fishes vary in phospholipid composition and membrane fluidity; Notothenia coriiceps HIF-1A mRNA, complete cds; Parachaenichthys charcoti HIF-1A mRNA, partial cds; Physical, chemical, and functional properties of neuronal membranes vary between species of Antarctic notothenioids differing in thermal tolerance; Thermal sensitivity of membrane fluidity and integrity in hearts of Antarctic fishes that vary in expression of hemoglobin and myoglobin", "datasets": [{"dataset_uid": "601406", "doi": "10.15784/601406", "keywords": "Antarctica; Antarctic Peninsula", "people": "O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Hypoxia response of hearts of Antarctic fishes", "url": "https://www.usap-dc.org/view/dataset/601406"}, {"dataset_uid": "601405", "doi": "10.15784/601405", "keywords": "Antarctica; Antarctic Peninsula", "people": "O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Cardiac metabolism in Antarctic fishes in response to an acute increase in temperature", "url": "https://www.usap-dc.org/view/dataset/601405"}, {"dataset_uid": "200192", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Chionodraco rastrospinosus HIF-1A mRNA, partial cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/kx950831"}, {"dataset_uid": "200185", "doi": "10.5061/dryad.k90h35k", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Mitochondrial membranes in cardiac muscle from Antarctic notothenioid fishes vary in phospholipid composition and membrane fluidity", "url": "https://doi.org/10.5061/dryad.k90h35k"}, {"dataset_uid": "200186", "doi": "10.5061/dryad.qm0b25h", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Physical, chemical, and functional properties of neuronal membranes vary between species of Antarctic notothenioids differing in thermal tolerance", "url": "https://doi.org/10.5061/dryad.qm0b25h"}, {"dataset_uid": "200187", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Chaenocephalus aceratus HIF-1A mRNA, complete cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX950828"}, {"dataset_uid": "200188", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Notothenia coriiceps HIF-1A mRNA, complete cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX950829"}, {"dataset_uid": "200189", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Eleginops maclovinus HIF-1A mRNA, partial cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX950830"}, {"dataset_uid": "601410", "doi": "10.15784/601410", "keywords": "Antarctica; Antarctic Peninsula; Biota; Fish", "people": "O\u0027Brien, Kristin; Crockett, Elizabeth; Egginton, Stuart; Axelsson, Michael; Farrell, Anthony; Joyce, William", "repository": "USAP-DC", "science_program": null, "title": "Effects of acute warming on cardiovascular performance of Antarctic fishes", "url": "https://www.usap-dc.org/view/dataset/601410"}, {"dataset_uid": "601409", "doi": "10.15784/601409", "keywords": "Antarctica; Antarctic Peninsula", "people": "Joyce, Michael; Axelsson, Michael; Farrell, Anthony; Egginton, Stuart; O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Adrenergic and adenosinergic regulation of the cardiovascular system in the Antarctic icefish Chaenocephalus aceratus", "url": "https://www.usap-dc.org/view/dataset/601409"}, {"dataset_uid": "601408", "doi": "10.15784/601408", "keywords": "Antarctica; Antarctic Peninsula", "people": "Crockett, Elizabeth; Joyce, William; Farrell, Anthony; Egginton, Stuart; Axelsson, Michael; O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Acclimation of cardiovascular function in Notothenia coriiceps", "url": "https://www.usap-dc.org/view/dataset/601408"}, {"dataset_uid": "601407", "doi": "10.15784/601407", "keywords": "Antarctica; Antarctic Peninsula", "people": "Axelsson, Michael; O\u0027Brien, Kristin; Joyce, William", "repository": "USAP-DC", "science_program": null, "title": "Measurements of splenic contraction in Antarctic fishes", "url": "https://www.usap-dc.org/view/dataset/601407"}, {"dataset_uid": "200191", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Gymnodraco acuticeps HIF-1A mRNA, partial cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/kx950832"}, {"dataset_uid": "601414", "doi": "10.15784/601414", "keywords": "Antarctica; Antarctic Peninsula", "people": "Crockett, Elizabeth; O\u0027Brien, Kristin; Evans, Elizabeth; Farnoud, Amir", "repository": "USAP-DC", "science_program": null, "title": "Thermal sensitivity of membrane fluidity and integrity in hearts of Antarctic fishes that vary in expression of hemoglobin and myoglobin", "url": "https://www.usap-dc.org/view/dataset/601414"}, {"dataset_uid": "200190", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Parachaenichthys charcoti HIF-1A mRNA, partial cds", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX950833"}, {"dataset_uid": "200184", "doi": "10.5061/dryad.83vc5", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Maximum cardiac performance of Antarctic fishes that lack haemoglobin and myoglobin: exploring the effect of warming on nature\u2019s natural knockouts", "url": "https://doi.org/10.5061/dryad.83vc5"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "The ocean surrounding Antarctica is home to an extraordinary assemblage of fishes, dominated by a single group that are extremely well-suited to life in icy waters and which are of significant ecological importance there. Of great concern is the capacity of these fishes to withstand increases in temperature as the region of the Western Antarctic Peninsula warms at a rate faster than any other area in the Southern hemisphere. One particular group of Antarctic fishes, known as the icefishes, are particularly vulnerable to increases in temperature because unlike all other vertebrates on earth, icefishes are white-blooded due to their lack of the oxygen-binding protein hemoglobin. This greatly reduces their capacity to transport and deliver oxygen to tissues compared to red-blooded Antarctic fishes. Previous studies have shown that icefishes are indeed less tolerant to elevations in temperature but the underlying factors are completely unknown. Additionally, it is not understood if red- or white-blooded Antarctic fishes can adjust, or acclimate, to modest increases in temperature, similar to those changes in temperature the animals might experience as the earth warms. The investigators will determine if heart function and/or nervous system function limits thermal tolerance of Antarctic fishes, and will determine their capacity to acclimate to warmer temperatures. The project will further the NSF goal of training new generations of scientists by training graduate and undergraduate students. In addition, the project will collaborate with a high school biology teacher from a school which serves a largely minority student body. The students will learn about the marine environment, and will construct a camera to be used in the field to learn more about Antarctic fishes. Two students and the teacher will also attend a summer marine biology internship program. Antarctic fishes within the suborder Notothenioidei (called \"notothenioids\") are among the organisms on earth least able to deal with changes in temperature. The hemoglobinless icefish are even less able to withstand temperature changes than are red-blooded notothenioids. While this is well documented, the underlying physiological and biochemical mechanisms responsible are unknown. The investigators will test the hypotheses that cardiac work is significantly greater in icefishes compared to red-blooded species, and that as temperature increases, the greater cardiac work of icefishes, coupled with reduced blood oxygen-carrying capacity, results in cardiac failure at a lower temperature compared to red-blooded species. They also hypothesize that neuronal function limits thermal tolerance of red-blooded notothenioids. These hypotheses will be tested using a wide variety of experiments. For example, the investigators will measure heart rate concurrently with critical thermal maximum. They will also characterize metabolic and gene-expression responses to elevated temperature and determine if mitochondrial function contributes to thermal tolerance using a variety of techniques. To determine if neuronal function limits thermal tolerance they will quantify behavioral responses to warming of whole animals and to warming of only the brain area. They will also determine if acclimation to warmer temperatures impacts heart function and they will measure activities of a variety of enzymes from central metabolic pathways.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Amd/Us; FISH; USA/NSF; FIELD INVESTIGATION; AMD; Antarctic Peninsula; LABORATORY; USAP-DC", "locations": "Antarctica; Antarctic Peninsula", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Crockett, Elizabeth; O\u0027Brien, Kristin", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "Dryad; GenBank; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes", "uid": "p0010084", "west": null}, {"awards": "1543383 Postlethwait, John", "bounds_geometry": "POLYGON((-66 -62,-65.2 -62,-64.4 -62,-63.6 -62,-62.8 -62,-62 -62,-61.2 -62,-60.4 -62,-59.6 -62,-58.8 -62,-58 -62,-58 -62.4,-58 -62.8,-58 -63.2,-58 -63.6,-58 -64,-58 -64.4,-58 -64.8,-58 -65.2,-58 -65.6,-58 -66,-58.8 -66,-59.6 -66,-60.4 -66,-61.2 -66,-62 -66,-62.8 -66,-63.6 -66,-64.4 -66,-65.2 -66,-66 -66,-66 -65.6,-66 -65.2,-66 -64.8,-66 -64.4,-66 -64,-66 -63.6,-66 -63.2,-66 -62.8,-66 -62.4,-66 -62))", "dataset_titles": "C. aceratus pronephric kidney (head kidney) miRNA; mirtop\r\ncommand lines tool to annotate miRNAs with a standard mirna/isomir naming; Patagonotothen cornucola isolate Pcor_18_01 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial; Patagonotothen sima isolate Psim_18_11 cardiac muscle myosin heavy chain 6 (myh6) gene, partial cds; Patagonotothen sima isolate Psim_18_11 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial; Patagonotothen sima isolate Psim_18_12 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial; Prost!, a tool for miRNA annotation and next generation smallRNA sequencing experiment analysis; Quantifying expression levels of smallRNAs between tissues in Danio Rerio strain AB.; Quantifying expression levels of smallRNAs between tissues in three-spined stickleback", "datasets": [{"dataset_uid": "200131", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Prost!, a tool for miRNA annotation and next generation smallRNA sequencing experiment analysis", "url": "https://github.com/uoregon-postlethwait/prost"}, {"dataset_uid": "200130", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "C. aceratus pronephric kidney (head kidney) miRNA", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=SRP069031"}, {"dataset_uid": "200129", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "Quantifying expression levels of smallRNAs between tissues in Danio Rerio strain AB.", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=SRP039502"}, {"dataset_uid": "200136", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Patagonotothen sima isolate Psim_18_11 cardiac muscle myosin heavy chain 6 (myh6) gene, partial cds", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=MN136234+"}, {"dataset_uid": "200135", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Patagonotothen sima isolate Psim_18_12 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=MN136233+"}, {"dataset_uid": "200128", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "Quantifying expression levels of smallRNAs between tissues in three-spined stickleback", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=SRP157992"}, {"dataset_uid": "200132", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "mirtop\r\ncommand lines tool to annotate miRNAs with a standard mirna/isomir naming", "url": "https://github.com/miRTop"}, {"dataset_uid": "200134", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Patagonotothen sima isolate Psim_18_11 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=MN136232"}, {"dataset_uid": "200133", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Patagonotothen cornucola isolate Pcor_18_01 cytochrome oxidase subunit 1 (COI) gene, partial cds; mitochondrial", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=MN136231"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "Icefish live in frigid Antarctic seas, and have unique traits such as the absence of red blood cells, enlarged hearts, large diameter blood vessels, low bone mineral densities, and fat droplets that disrupt their muscles. These features would be harmful in other animals. In mammals and fish inhabiting warm waters, development of organs involved in these traits is modulated by genes that encode specific proteins, but the rate of protein production is often regulated by short RNA molecules called microRNAs (miRNAs). Genes that code for proteins must first make an RNA copy, and the actual protein is made from this RNA copy intermediate. MiRNAs regulate the amount of protein that is made by binding to the RNA intermediate and interrupting its production of protein. Binding of miRNAs to RNA depends strongly on temperature. Regulation of genes by miRNAs has not been studied in Antarctic fish, which live in seas with temperatures below the freezing point of fresh water. This project will compare miRNA regulation 1) in Antarctic fish vs. warm-water fish to learn how miRNAs regulate gene expression in constant cold; and 2) in Antarctic icefish with no red blood cells, enlarged hearts, and reduced bone density vs. closely related Antarctic fish containing red blood cells, normal hearts, and dense bones. The project will have broad impacts to science and society nationally and globally. First, this will be the first study of important factors in gene regulation (miRNAs) in Antarctic fish, which are an essential component of the entire ecology of the Southern Ocean, and will shed light on how these fish might respond to the warming of Antarctic waters. Second, it will bring Antarctic science to under-represented high school students at a local alternative downtown high school by conducting video conferences during the Antarctic field seasons and hosting student investigations of Antarctic fish in the research laboratory. microRNAs (miRNAs) are key post-transcriptional regulators of gene expression that modulate development and physiology in temperate animals. Although miRNAs act by binding to messenger RNAs (mRNAs), a process that is strongly sensitive to temperature, miRNAs have yet not been studied in Antarctic animals, including Notothenioid fish, which dominate the Southern Ocean. This project will compare miRNA regulation in 1) Antarctic vs. temperate fish to learn the roles of miRNA regulation in adaptation to constant cold; and in 2) bottom-dwelling, dense-boned, red-blooded Nototheniods vs. high buoyancy, osteopenic, white-blooded icefish to understand miRNA regulation in specialized organs after the evolution of the loss of hemoglobin genes and red blood cells, the origin of enlarged heart and vasculature, and the evolution of increased buoyancy, which arose by decreased bone mineralization and increased lipid deposition. Aim 1 is to test the hypothesis that Antarctic fish evolved miRNA-related genome specializations in response to constant cold. The project will compare four Antarctic Notothenioid species to two temperate Notothenioids and two temperate laboratory species to test the hypotheses that (a) Antarctic fish evolved miRNA genome repertoires by loss of ancestral genes and/or gain of new genes, (b) express miRNAs that are involved in cold tolerance, and (c) respond to temperature change by changing miRNA gene expression. Aim 2 is to test the hypothesis that the evolution of icefish from red-blooded bottom-dwelling ancestors was accompanied by an altered miRNA genomic repertoire, sequence, and/or expression. The project will test the hypotheses that (a) miRNAs in icefish evolved in sequence and/or in expression in icefish specializations, including head kidney (origin of red blood cells); heart (changes in vascular system), cranium and pectoral girdle (reduced bone mineral density); and skeletal muscle (lipid deposition), and (b) miRNAs that evolved in icefish specializations had ancestral functions related to their derived roles in icefish, as determined by functional tests of zebrafish orthologs of icefish miRNAs in developing zebrafish. The program will isolate, sequence, and determine the expression of miRNAs and mRNAs using high-throughput transcriptomics and novel software. Results will show how the microRNA system evolves in vertebrate animals pushed to physiological extremes and provide insights into the prospects of key species in the most rapidly warming part of the globe.", "east": -58.0, "geometry": "POINT(-62 -64)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; Palmer Station; NOT APPLICABLE; FISH", "locations": "Palmer Station", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Postlethwait, John; Desvignes, Thomas", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "GitHub", "repositories": "GitHub; NCBI GenBank; NCBI SRA", "science_programs": null, "south": -66.0, "title": "Antarctic Fish and MicroRNA Control of Development and Physiology", "uid": "p0010085", "west": -66.0}, {"awards": "1341701 Bilyk, Kevin", "bounds_geometry": null, "dataset_titles": "Antarctic Ice fish; submission ID #SRP113562", "datasets": [{"dataset_uid": "000206", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Antarctic Ice fish; submission ID #SRP113562", "url": "https://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Mon, 31 Jul 2017 00:00:00 GMT", "description": "This work will broaden our knowledge and insights into genetic trait loss or change accompanying species evolution in general as well as within the uniquely isolated and frigid Southern Ocean. The system of oxygen-carrying and related proteins being studied is very important to human health and the two proteins being specifically studied in this work (haptoglobin and hemopexin) have crucial roles in preventing excess iron loading in the kidneys. As such, the project has the potential to contribute novel insights that could be valuable to medical science. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The lead principal investigator on the project is an early career scientist whose career development will be enhanced by this project. It will also support the training of several undergraduate students in molecular biology, protein biochemistry, and appreciation of the unique Antarctic fish fauna and environment. The project will contribute to a content-rich web site that will bring to the public the history of biological discoveries and sciences on fishes of the Southern Ocean and through this project the investigators will contribute to an annual polar event at a children\u0027s science museum. The Antarctic icefishes have thrived despite the striking evolutionary loss of the normally indispensable respiratory protein hemoglobin in all species and myoglobin in some. Studies over the past decades have predominately focused on the mechanisms behind hemoprotein losses and the resulting compensatory adaptations in these fish, while evolutionary impact of such losses on the supporting protein genes and functions has remained unaddressed. This project investigates the evolutionary fate of two important partner proteins, the hemoglobin scavenger haptoglobin and the heme scavenger hemopexin (heme groups are the iron-containing functional group of proteins such as hemoglobin and myoglobin). With the permanent hemoglobin-null state in Antarctic icefishes, and particularly in dual hemoglobin- and myoglobin-null species, the preservation of a functional haptoglobin would seem unessential and the role of hemopexin likely diminished. This project seeks to resolve whether co-evolutionary loss or reduction of these supporting proteins occurred with the extinction of the hemoglobin trait in the icefishes, and the molecular mechanisms underlying such changes. The investigators envisage the cold and oxygen rich marine environment as the start of a cascade of relaxation of selection pressures. Initially this would have obviated the need for maintaining functional oxygen carrying proteins, ultimately leading to their permanent loss. These events in turn would have relaxed the maintenance of the network of supporting systems, leading to additional trait loss or change.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Bilyk, Kevin", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": null, "title": "Evolutionary Fates of Hemoglobin and Heme Scavengers in White-blooded Antarctic Icefishes", "uid": "p0000396", "west": null}, {"awards": "1043781 O\u0027Brien, Kristin; 1043576 Crockett, Elizabeth", "bounds_geometry": "POLYGON((-64.45 -63.467,-64.2633 -63.467,-64.0766 -63.467,-63.8899 -63.467,-63.7032 -63.467,-63.5165 -63.467,-63.3298 -63.467,-63.1431 -63.467,-62.9564 -63.467,-62.7697 -63.467,-62.583 -63.467,-62.583 -63.5653,-62.583 -63.6636,-62.583 -63.7619,-62.583 -63.8602,-62.583 -63.9585,-62.583 -64.0568,-62.583 -64.1551,-62.583 -64.2534,-62.583 -64.3517,-62.583 -64.45,-62.7697 -64.45,-62.9564 -64.45,-63.1431 -64.45,-63.3298 -64.45,-63.5165 -64.45,-63.7032 -64.45,-63.8899 -64.45,-64.0766 -64.45,-64.2633 -64.45,-64.45 -64.45,-64.45 -64.3517,-64.45 -64.2534,-64.45 -64.1551,-64.45 -64.0568,-64.45 -63.9585,-64.45 -63.8602,-64.45 -63.7619,-64.45 -63.6636,-64.45 -63.5653,-64.45 -63.467))", "dataset_titles": "Electronic fishing logs; Expedition data of LMG1104; Redox Balance in Antarctic Notothenioid Fishes", "datasets": [{"dataset_uid": "600382", "doi": "10.15784/600382", "keywords": "Antarctica; Antarctic Peninsula; Biota; Fish; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Redox Balance in Antarctic Notothenioid Fishes", "url": "https://www.usap-dc.org/view/dataset/600382"}, {"dataset_uid": "600390", "doi": "10.15784/600390", "keywords": "Antarctica; Biota; Southern Ocean", "people": "Crockett, Elizabeth", "repository": "USAP-DC", "science_program": null, "title": "Electronic fishing logs", "url": "https://www.usap-dc.org/view/dataset/600390"}, {"dataset_uid": "002687", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1104", "url": "https://www.rvdata.us/search/cruise/LMG1104"}], "date_created": "Tue, 06 Dec 2016 00:00:00 GMT", "description": "Antarctic channichthyid icefishes are stunning examples of the unique physiological traits that can arise during evolution in a constantly cold environment. Icefishes are the only vertebrates that as adults, lack the circulating oxygen-binding protein hemoglobin (Hb); several species within this family also lack the intracellular oxygen-binding protein myoglobin (Mb) in their heart ventricle. The loss of Hb and Mb has resulted in striking modifications in the cardiovascular system to ensure adequate tissue oxygenation, some of which are energetically costly. Recent indicate there may be at least one benefit to not expressing these heme-centered proteins - oxidized proteins and lipids are higher in red-blooded notothenioids compared to icefishes. The research will address the hypothesis that the loss of Hb and Mb reduces oxidative stress in icefishes compared to red-blooded notothenioid fishes, resulting in a lower rate of protein turnover and energetic cost savings. Specifically, the project will (1) Characterize levels of oxidative stress in red- and white-blooded notothenioid fishes, (2) Determine if red- and white-blooded notothenioids differ in their regulation of iron, (3) Determine if lower levels of oxidized proteins in icefishes result in lower rates of protein turnover and energetic cost savings, and (4) Determine if oxygen-binding proteins promote oxidative stress in-vivo and in-vitro. The results will contribute to the understanding of iron-catalyzed oxidative stress, which is associated with the progression of Alzheimer\u0027s, Parkinson\u0027s and cardiovascular diseases. Moreover, the research will increase understanding of factors related to iron metabolism and oxidative stress in notothenioid fishes that may have played key roles in the success of channichthyid icefishes. The broader impacts include development of a website will enable teachers and students to learn more about the fascinating biology of Antarctic icefishes, as well as the impacts of global climate change and commercial fishing activities on Antarctic fishes. Additionally, Alaska Native high school and undergraduate students will be involved in research at the University of Alaska, Fairbanks.", "east": -62.583, "geometry": "POINT(-63.5165 -63.9585)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Not provided; R/V LMG", "locations": null, "north": -63.467, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Crockett, Elizabeth; O\u0027Brien, Kristin", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -64.45, "title": "Collaborative research: Redox Balance in Antarctic Notothenioid fishes: Do Icefishes have an Advantage?", "uid": "p0000320", "west": -64.45}, {"awards": "0741301 O\u0027Brien, Kristin; 1142720 Crockett, Elizabeth", "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 -63.370999999999995,-62.44 -63.452,-62.44 -63.533,-62.44 -63.614,-62.44 -63.69499999999999,-62.44 -63.775999999999996,-62.44 -63.857,-62.44 -63.937999999999995,-62.44 -64.01899999999999,-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 -64.01899999999999,-64.45 -63.937999999999995,-64.45 -63.857,-64.45 -63.775999999999996,-64.45 -63.69499999999999,-64.45 -63.614,-64.45 -63.533,-64.45 -63.452,-64.45 -63.370999999999995,-64.45 -63.29))", "dataset_titles": "Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes", "datasets": [{"dataset_uid": "600084", "doi": "10.15784/600084", "keywords": "Biota; Oceans; Pot; Southern Ocean; Trawl", "people": "O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes", "url": "https://www.usap-dc.org/view/dataset/600084"}], "date_created": "Sat, 30 Nov 2013 00:00:00 GMT", "description": "Abstract 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.", "east": -62.44, "geometry": "POINT(-63.445 -63.695)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -63.29, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Crockett, Elizabeth; O\u0027Brien, Kristin", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.1, "title": "Collaborative Research: Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes", "uid": "p0000483", "west": -64.45}, {"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))", "dataset_titles": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "datasets": [{"dataset_uid": "600057", "doi": "10.15784/600057", "keywords": "Antarctica; Biota; Oceans; Penguin; Southern Ocean", "people": "Ponganis, Paul", "repository": "USAP-DC", "science_program": null, "title": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "url": "https://www.usap-dc.org/view/dataset/600057"}], "date_created": "Sun, 20 Dec 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, \"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.", "east": 166.317, "geometry": "POINT(166.15 -77.7165)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.683, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ponganis, Paul", "platforms": "Not provided", "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": "p0000535", "west": 165.983}, {"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))", "dataset_titles": "Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis; Expedition Data; Expedition data of LMG0705; Expedition data of LMG0706", "datasets": [{"dataset_uid": "001534", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0705"}, {"dataset_uid": "002712", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0705", "url": "https://www.rvdata.us/search/cruise/LMG0705"}, {"dataset_uid": "002713", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0706", "url": "https://www.rvdata.us/search/cruise/LMG0706"}, {"dataset_uid": "600039", "doi": "10.15784/600039", "keywords": "Biota; Oceans; Pot; Sample/collection Description; Sample/Collection Description; Southern Ocean; Trawl", "people": "Sidell, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis", "url": "https://www.usap-dc.org/view/dataset/600039"}], "date_created": "Sun, 06 Dec 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. \u003cbr/\u003eFew 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. \u003cbr/\u003eWithin 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 implicated 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)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS", "is_usap_dc": true, "keywords": "R/V LMG; Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sidell, Bruce", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis.", "uid": "p0000527", "west": -180.0}]
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Project Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Dataset Links and Repositories | Abstract | Bounds Geometry | Geometry | Selected | Visible | |||||||
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Evolution of hemoglobin genes in notothenioid fishes
|
1543383 1947040 2232891 |
2023-05-03 | Desvignes, Thomas; Postlethwait, John | Antarctic notothenioid fishes, also known as cryonotothenioids, inhabit the icy and highly oxygenated waters surrounding the Antarctic continent after diverging from notothenioids inhabiting more temperate waters. Notothenioid hemoglobin and blood parameters are known to have evolved along with the establishment of stable polar conditions, and among Antarctic notothenioids, icefishes are evolutionary oddities living without hemoglobin following the deletion of all functional hemoglobin genes from their genomes. In this project, we investigate the evolution of hemoglobin genes and gene clusters across the notothenioid radiation until their loss in the icefish ancestor after its divergence from the dragonfish lineage to understand the forces, mechanisms, and potential causes for hemoglobin gene loss in the icefish ancestor. | 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 | ||||||||
Evolutionary Genomic Responses in Antarctic Notothenioid Fishes
|
1645087 |
2022-10-10 | Catchen, Julian; Cheng, Chi-Hing | As plate tectonics pushed Antarctica into a polar position, by ~34 million years ago, the continent and its surrounding Southern Ocean (SO) became geographically and thermally isolated by the Antarctic Circumpolar Current. Terrestrial and marine glaciation followed, resulting in extinctions as well as the survival and radiation of unique flora and fauna. The notothenioid fish survived and arose from a common ancestral stock into tax with 120 species that dominates today?s SO fish fauna. The Notothenioids evolved adaptive traits including novel antifreeze proteins for survival in extreme cold, but also suffered seemingly adverse trait loss including red blood cells in the icefish family, and the ability to mount cellular responses to mitigate heat stress ? otherwise ubiquitous across all life. This project aims to understand how the notothenoid genomes have changed and contributed to their evolution in the cold. The project will sequence, analyze and compare the genomes of two strategic pairs of notothenioid fishes representing both red-blooded and white-blooded species. Each pair will consist of one Antarctic species and one that has readapted to the temperate waters of S. America or New Zealand. The project will also compare the Antarctic species genomes to a genome of the closet non-Antarctic relative representing the temperate notothenioid ancestor. The work aims to uncover the mechanisms that enabled the adaptive evolution of this ecologically vital group of fish in the freezing Southern Ocean, and shed light on their adaptability to a warming world. The finished genomes will be made available to promote and advance Antarctic research and the project will host a symposium of Polar researchers to discuss the cutting edge developments regarding of genomic adaptations in the polar region. Despite subzero, icy conditions that are perilous to teleost fish, the fish fauna of the isolated Southern Ocean (SO) surrounding Antarctica is remarkably bountiful. A single teleost group ? the notothenioid fishes ? dominate the fauna, comprising over 120 species that arose from a common ancestor. When Antarctica became isolated and SO temperatures began to plunge in early Oligocene, the prior temperate fishes became extinct. The ancestor of Antarctic notothenioids overcame forbidding polar conditions and, absent niche competition, it diversified and filled the SO. How did notothenioids adapt to freezing environmental selection pressures and achieve such extraordinary success? And having specialized to life in chronic cold for 30 myr, can they evolve in pace with today?s warming climate to stay viable? Past studies of Antarctic notothenioid evolutionary adaptation have discovered various remarkable traits including the key, life-saving antifreeze proteins. But life specialized to cold also led to paradoxical trait changes such as the loss of the otherwise universal heat shock response, and of the O2-transporting hemoglobin and red blood cells in the icefish family. A few species interestingly regained abilities to live in temperate waters following the escape of their ancestor out of the freezing SO. This proposed project is the first major effort to advance the field from single trait studies to understanding the full spectrum of genomic and genetic responses to climatic and environmental change during notothenioid evolution, and to evaluate their adaptability to continuing climate change. To this end, the project will sequence the genomes of four key species that embody genomic responses to different thermal selection regimes during notothenioids? evolutionary history, and by comparative analyses of genomic structure, architecture and content, deduce the responding changes. Specifically, the project will (i) obtain whole genome assemblies of the red-blooded T. borchgrevinki and the S. American icefish C. esox; (ii) using the finished genomes from (i) as template, obtain assemblies of the New Zealand notothenioid N. angustata, and the white-blooded icefish C. gunnari, representing a long (11 myr) and recent (1 myr) secondarily temperate evolutionary history respectively. Genes that are under selection in the temperate environment but not in the Antarctic environment can be inferred to be directly necessary for that environment ? and the reverse is also true for genes under selection in the Antarctic but not in the temperate environment. Further, genes important for survival in temperate waters will show parallel selection between N. angustata and C. esox despite the fact that the two fish left the Antarctic at far separated time points. Finally, gene families that expanded due to strong selection within the cold Antarctic should show a degradation of duplicates in the temperate environment. The project will test these hypotheses using a number of techniques to compare the content and form of genes, the structure of the chromosomes containing those genes, and through the identification of key characters, such as selfish genetic elements, introns, and structural variants. | None | None | false | false | ||||||||
Foraging Ecology of Crabeater Seals (Lobodon Carcinophagus)
|
0003956 9981683 |
2022-06-29 | Burns, Jennifer; Costa, Daniel |
|
This collaborative study between the University of California, Santa Cruz, Duke University, the University of South Florida, the University of Alaska-Anchorage, and the University of California, San Diego will examine the identification of biological and physical features associated with the abundance and distribution of individual Antarctic predators; the identification and characterization of biological 'hot spots' within the Western Antarctic Peninsula; and the development of temporally and spatially explicit models of krill consumption within the WAP by vertebrate predators. It is one of several data synthesis and modeling components that use the data obtained in the course of the field work of the Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) experiment.<br/>SO-Globec is a multidisciplinary effort focused on understanding the physical and biological factors that influence growth, reproduction, recruitment and survival of Antarctic krill (Euphausia superba). The program uses a multi-trophic level approach that includes the predators and competitors of Antarctic krill, represented by other zooplankton, fish, penguins, seals, and cetaceans. It is currently in a synthesis and modeling phase. This collaborative project is concerned with understanding how predators utilize 'hot spots', i.e. locally intense areas of biological productivity, and how 'hot spots' might temporally and spatially structure krill predation rates, and will be integrated with other synthesis and modeling studies that deal with the hydrography primary production, and krill dynamics. | 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 | |||||||
ANT LIA: Hypoxia Tolerance in Notothenioid Fishes
|
1954241 |
2021-08-17 | O'Brien, Kristin | No dataset link provided | Part 1: Non-technical description: Global climate warming is increasing the frequency and severity of low oxygen events in marine and freshwater environments worldwide, and these events threaten the health of aquatic ecosystems and the viability of fish populations. The Southern Ocean surrounding Antarctica has historically been a stable, icy-cold, and oxygen-rich environment, but is now warming at an unprecedented rate and faster than all other regions in the Southern hemisphere. Antarctic fishes have evolved in sub-zero temperatures that have been stable over long periods of time with traits allowing them to thrive in frigid waters, but with diminished resilience to warming temperatures. Presently little is known about the ability of Antarctic fishes to withstand hypoxic, or low-oxygen, conditions that often accompany warming. This research will investigate the hypoxia tolerance of four species of Antarctic fishes, including two species of icefishes that lack the oxygen-carrying protein, hemoglobin, which may compromise their ability to oxygenate tissues under hypoxic conditions. The hypoxia tolerance of four Antarctic fish species will be compared to that of a related fish species inhabiting warmer coastal regions of South America. Physiological and biochemical responses to hypoxia will be evaluated and compared amongst the five species to bolster our predictions of the capacity of Antarctic fishes to cope with a changing environment. This research will provide training opportunities for undergraduate and graduate students, and a postdoctoral research fellow. A year-long seminar series hosted by the Aquarium of the Pacific will feature female scientists who work in Antarctica to inspire youth in the greater Los Angeles area to pursue careers in science. Part 2: Technical description: The overarching hypothesis to be tested in this project is that the long evolution of Antarctic notothenioid fishes in a cold, oxygen-rich environment has reduced their capacity to mount a robust physiological, biochemical, and molecular response to hypoxia compared to related, cold-temperate fish species. Hypoxia tolerance will be compared among the red-blooded Antarctic notothenioids, Notothenia coriiceps and Notothenia rossii; the hemoglobinless Antarctic icefishes, Chaenocephalus aceratus and Chionodraco rastrospinosus; and the basal, cold-temperate notothenioid, Eleginops maclovinus, a species that has never inhabited waters south of the Polar Front. The minimum level of oxygen required to sustain maintenance metabolic requirements (O2crit) will be quantified. Animals will then be exposed to 65% of O2crit for 48 hours, and responses to hypoxia will be evaluated by measuring hematocrit and hemoglobin levels, as well as metabolites in brain, liver, glycolytic and cardiac muscles. Maximal activities of key enzymes of aerobic and anaerobic metabolism will be quantified to assess capacities for synthesizing ATP in hypoxic conditions. Gill remodeling will be analyzed using light and scanning electron microscopy. The molecular response to hypoxia will be characterized in liver and brains by quantifying levels of the master transcriptional regulator of oxygen homeostasis, hypoxia-inducible factor-1 (HIF-1), and hypoxic gene expression will be quantified using RNA-Seq. Cell cultures will be used to determine if a previously identified insertion mutation in notothenioid HIF-1 affects the ability of HIF-1 to drive gene expression and thus, hypoxia tolerance. The results of this project will provide the most comprehensive assessment of the hypoxia tolerance of Antarctic fishes to date. Broader impacts include research training opportunities for undergraduate and graduate students and a postdoctoral research associate, with a focus on involving Native Alaskan students in research. In partnership with the Aquarium of the Pacific, a year-long public seminar series will be held, showcasing the research and careers of 9 women who conduct research in Antarctica. The goal of the series is to cultivate and empower a community of middle and high school students in the greater Los Angeles area to pursue their interests in science and related fields, and to enhance the public engagement capacities of research scientists so that they may better inspire youth and early career scientists in STEM fields. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. | None | None | false | false | |||||||
Collaborative Research: The Physiological and Biochemical Underpinnings of Thermal Tolerance in Antarctic Notothenioid Fishes
|
1341602 1341663 |
2020-02-26 | Crockett, Elizabeth; O'Brien, Kristin | The ocean surrounding Antarctica is home to an extraordinary assemblage of fishes, dominated by a single group that are extremely well-suited to life in icy waters and which are of significant ecological importance there. Of great concern is the capacity of these fishes to withstand increases in temperature as the region of the Western Antarctic Peninsula warms at a rate faster than any other area in the Southern hemisphere. One particular group of Antarctic fishes, known as the icefishes, are particularly vulnerable to increases in temperature because unlike all other vertebrates on earth, icefishes are white-blooded due to their lack of the oxygen-binding protein hemoglobin. This greatly reduces their capacity to transport and deliver oxygen to tissues compared to red-blooded Antarctic fishes. Previous studies have shown that icefishes are indeed less tolerant to elevations in temperature but the underlying factors are completely unknown. Additionally, it is not understood if red- or white-blooded Antarctic fishes can adjust, or acclimate, to modest increases in temperature, similar to those changes in temperature the animals might experience as the earth warms. The investigators will determine if heart function and/or nervous system function limits thermal tolerance of Antarctic fishes, and will determine their capacity to acclimate to warmer temperatures. The project will further the NSF goal of training new generations of scientists by training graduate and undergraduate students. In addition, the project will collaborate with a high school biology teacher from a school which serves a largely minority student body. The students will learn about the marine environment, and will construct a camera to be used in the field to learn more about Antarctic fishes. Two students and the teacher will also attend a summer marine biology internship program. Antarctic fishes within the suborder Notothenioidei (called "notothenioids") are among the organisms on earth least able to deal with changes in temperature. The hemoglobinless icefish are even less able to withstand temperature changes than are red-blooded notothenioids. While this is well documented, the underlying physiological and biochemical mechanisms responsible are unknown. The investigators will test the hypotheses that cardiac work is significantly greater in icefishes compared to red-blooded species, and that as temperature increases, the greater cardiac work of icefishes, coupled with reduced blood oxygen-carrying capacity, results in cardiac failure at a lower temperature compared to red-blooded species. They also hypothesize that neuronal function limits thermal tolerance of red-blooded notothenioids. These hypotheses will be tested using a wide variety of experiments. For example, the investigators will measure heart rate concurrently with critical thermal maximum. They will also characterize metabolic and gene-expression responses to elevated temperature and determine if mitochondrial function contributes to thermal tolerance using a variety of techniques. To determine if neuronal function limits thermal tolerance they will quantify behavioral responses to warming of whole animals and to warming of only the brain area. They will also determine if acclimation to warmer temperatures impacts heart function and they will measure activities of a variety of enzymes from central metabolic pathways. | None | None | false | false | ||||||||
Antarctic Fish and MicroRNA Control of Development and Physiology
|
1543383 |
2020-02-26 | Postlethwait, John; Desvignes, Thomas | Icefish live in frigid Antarctic seas, and have unique traits such as the absence of red blood cells, enlarged hearts, large diameter blood vessels, low bone mineral densities, and fat droplets that disrupt their muscles. These features would be harmful in other animals. In mammals and fish inhabiting warm waters, development of organs involved in these traits is modulated by genes that encode specific proteins, but the rate of protein production is often regulated by short RNA molecules called microRNAs (miRNAs). Genes that code for proteins must first make an RNA copy, and the actual protein is made from this RNA copy intermediate. MiRNAs regulate the amount of protein that is made by binding to the RNA intermediate and interrupting its production of protein. Binding of miRNAs to RNA depends strongly on temperature. Regulation of genes by miRNAs has not been studied in Antarctic fish, which live in seas with temperatures below the freezing point of fresh water. This project will compare miRNA regulation 1) in Antarctic fish vs. warm-water fish to learn how miRNAs regulate gene expression in constant cold; and 2) in Antarctic icefish with no red blood cells, enlarged hearts, and reduced bone density vs. closely related Antarctic fish containing red blood cells, normal hearts, and dense bones. The project will have broad impacts to science and society nationally and globally. First, this will be the first study of important factors in gene regulation (miRNAs) in Antarctic fish, which are an essential component of the entire ecology of the Southern Ocean, and will shed light on how these fish might respond to the warming of Antarctic waters. Second, it will bring Antarctic science to under-represented high school students at a local alternative downtown high school by conducting video conferences during the Antarctic field seasons and hosting student investigations of Antarctic fish in the research laboratory. microRNAs (miRNAs) are key post-transcriptional regulators of gene expression that modulate development and physiology in temperate animals. Although miRNAs act by binding to messenger RNAs (mRNAs), a process that is strongly sensitive to temperature, miRNAs have yet not been studied in Antarctic animals, including Notothenioid fish, which dominate the Southern Ocean. This project will compare miRNA regulation in 1) Antarctic vs. temperate fish to learn the roles of miRNA regulation in adaptation to constant cold; and in 2) bottom-dwelling, dense-boned, red-blooded Nototheniods vs. high buoyancy, osteopenic, white-blooded icefish to understand miRNA regulation in specialized organs after the evolution of the loss of hemoglobin genes and red blood cells, the origin of enlarged heart and vasculature, and the evolution of increased buoyancy, which arose by decreased bone mineralization and increased lipid deposition. Aim 1 is to test the hypothesis that Antarctic fish evolved miRNA-related genome specializations in response to constant cold. The project will compare four Antarctic Notothenioid species to two temperate Notothenioids and two temperate laboratory species to test the hypotheses that (a) Antarctic fish evolved miRNA genome repertoires by loss of ancestral genes and/or gain of new genes, (b) express miRNAs that are involved in cold tolerance, and (c) respond to temperature change by changing miRNA gene expression. Aim 2 is to test the hypothesis that the evolution of icefish from red-blooded bottom-dwelling ancestors was accompanied by an altered miRNA genomic repertoire, sequence, and/or expression. The project will test the hypotheses that (a) miRNAs in icefish evolved in sequence and/or in expression in icefish specializations, including head kidney (origin of red blood cells); heart (changes in vascular system), cranium and pectoral girdle (reduced bone mineral density); and skeletal muscle (lipid deposition), and (b) miRNAs that evolved in icefish specializations had ancestral functions related to their derived roles in icefish, as determined by functional tests of zebrafish orthologs of icefish miRNAs in developing zebrafish. The program will isolate, sequence, and determine the expression of miRNAs and mRNAs using high-throughput transcriptomics and novel software. Results will show how the microRNA system evolves in vertebrate animals pushed to physiological extremes and provide insights into the prospects of key species in the most rapidly warming part of the globe. | POLYGON((-66 -62,-65.2 -62,-64.4 -62,-63.6 -62,-62.8 -62,-62 -62,-61.2 -62,-60.4 -62,-59.6 -62,-58.8 -62,-58 -62,-58 -62.4,-58 -62.8,-58 -63.2,-58 -63.6,-58 -64,-58 -64.4,-58 -64.8,-58 -65.2,-58 -65.6,-58 -66,-58.8 -66,-59.6 -66,-60.4 -66,-61.2 -66,-62 -66,-62.8 -66,-63.6 -66,-64.4 -66,-65.2 -66,-66 -66,-66 -65.6,-66 -65.2,-66 -64.8,-66 -64.4,-66 -64,-66 -63.6,-66 -63.2,-66 -62.8,-66 -62.4,-66 -62)) | POINT(-62 -64) | false | false | ||||||||
Evolutionary Fates of Hemoglobin and Heme Scavengers in White-blooded Antarctic Icefishes
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1341701 |
2017-07-31 | Bilyk, Kevin |
|
This work will broaden our knowledge and insights into genetic trait loss or change accompanying species evolution in general as well as within the uniquely isolated and frigid Southern Ocean. The system of oxygen-carrying and related proteins being studied is very important to human health and the two proteins being specifically studied in this work (haptoglobin and hemopexin) have crucial roles in preventing excess iron loading in the kidneys. As such, the project has the potential to contribute novel insights that could be valuable to medical science. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The lead principal investigator on the project is an early career scientist whose career development will be enhanced by this project. It will also support the training of several undergraduate students in molecular biology, protein biochemistry, and appreciation of the unique Antarctic fish fauna and environment. The project will contribute to a content-rich web site that will bring to the public the history of biological discoveries and sciences on fishes of the Southern Ocean and through this project the investigators will contribute to an annual polar event at a children's science museum. The Antarctic icefishes have thrived despite the striking evolutionary loss of the normally indispensable respiratory protein hemoglobin in all species and myoglobin in some. Studies over the past decades have predominately focused on the mechanisms behind hemoprotein losses and the resulting compensatory adaptations in these fish, while evolutionary impact of such losses on the supporting protein genes and functions has remained unaddressed. This project investigates the evolutionary fate of two important partner proteins, the hemoglobin scavenger haptoglobin and the heme scavenger hemopexin (heme groups are the iron-containing functional group of proteins such as hemoglobin and myoglobin). With the permanent hemoglobin-null state in Antarctic icefishes, and particularly in dual hemoglobin- and myoglobin-null species, the preservation of a functional haptoglobin would seem unessential and the role of hemopexin likely diminished. This project seeks to resolve whether co-evolutionary loss or reduction of these supporting proteins occurred with the extinction of the hemoglobin trait in the icefishes, and the molecular mechanisms underlying such changes. The investigators envisage the cold and oxygen rich marine environment as the start of a cascade of relaxation of selection pressures. Initially this would have obviated the need for maintaining functional oxygen carrying proteins, ultimately leading to their permanent loss. These events in turn would have relaxed the maintenance of the network of supporting systems, leading to additional trait loss or change. | None | None | false | false | |||||||
Collaborative research: Redox Balance in Antarctic Notothenioid fishes: Do Icefishes have an Advantage?
|
1043781 1043576 |
2016-12-06 | Crockett, Elizabeth; O'Brien, Kristin |
|
Antarctic channichthyid icefishes are stunning examples of the unique physiological traits that can arise during evolution in a constantly cold environment. Icefishes are the only vertebrates that as adults, lack the circulating oxygen-binding protein hemoglobin (Hb); several species within this family also lack the intracellular oxygen-binding protein myoglobin (Mb) in their heart ventricle. The loss of Hb and Mb has resulted in striking modifications in the cardiovascular system to ensure adequate tissue oxygenation, some of which are energetically costly. Recent indicate there may be at least one benefit to not expressing these heme-centered proteins - oxidized proteins and lipids are higher in red-blooded notothenioids compared to icefishes. The research will address the hypothesis that the loss of Hb and Mb reduces oxidative stress in icefishes compared to red-blooded notothenioid fishes, resulting in a lower rate of protein turnover and energetic cost savings. Specifically, the project will (1) Characterize levels of oxidative stress in red- and white-blooded notothenioid fishes, (2) Determine if red- and white-blooded notothenioids differ in their regulation of iron, (3) Determine if lower levels of oxidized proteins in icefishes result in lower rates of protein turnover and energetic cost savings, and (4) Determine if oxygen-binding proteins promote oxidative stress in-vivo and in-vitro. The results will contribute to the understanding of iron-catalyzed oxidative stress, which is associated with the progression of Alzheimer's, Parkinson's and cardiovascular diseases. Moreover, the research will increase understanding of factors related to iron metabolism and oxidative stress in notothenioid fishes that may have played key roles in the success of channichthyid icefishes. The broader impacts include development of a website will enable teachers and students to learn more about the fascinating biology of Antarctic icefishes, as well as the impacts of global climate change and commercial fishing activities on Antarctic fishes. Additionally, Alaska Native high school and undergraduate students will be involved in research at the University of Alaska, Fairbanks. | POLYGON((-64.45 -63.467,-64.2633 -63.467,-64.0766 -63.467,-63.8899 -63.467,-63.7032 -63.467,-63.5165 -63.467,-63.3298 -63.467,-63.1431 -63.467,-62.9564 -63.467,-62.7697 -63.467,-62.583 -63.467,-62.583 -63.5653,-62.583 -63.6636,-62.583 -63.7619,-62.583 -63.8602,-62.583 -63.9585,-62.583 -64.0568,-62.583 -64.1551,-62.583 -64.2534,-62.583 -64.3517,-62.583 -64.45,-62.7697 -64.45,-62.9564 -64.45,-63.1431 -64.45,-63.3298 -64.45,-63.5165 -64.45,-63.7032 -64.45,-63.8899 -64.45,-64.0766 -64.45,-64.2633 -64.45,-64.45 -64.45,-64.45 -64.3517,-64.45 -64.2534,-64.45 -64.1551,-64.45 -64.0568,-64.45 -63.9585,-64.45 -63.8602,-64.45 -63.7619,-64.45 -63.6636,-64.45 -63.5653,-64.45 -63.467)) | POINT(-63.5165 -63.9585) | false | false | |||||||
Collaborative Research: Linkages among Mitochondrial Form, Function and Thermal Tolerance of Antarctic Notothenioid Fishes
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0741301 1142720 |
2013-11-30 | Crockett, Elizabeth; O'Brien, Kristin |
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Abstract 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 -63.370999999999995,-62.44 -63.452,-62.44 -63.533,-62.44 -63.614,-62.44 -63.69499999999999,-62.44 -63.775999999999996,-62.44 -63.857,-62.44 -63.937999999999995,-62.44 -64.01899999999999,-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 -64.01899999999999,-64.45 -63.937999999999995,-64.45 -63.857,-64.45 -63.775999999999996,-64.45 -63.69499999999999,-64.45 -63.614,-64.45 -63.533,-64.45 -63.452,-64.45 -63.370999999999995,-64.45 -63.29)) | POINT(-63.445 -63.695) | false | false | |||||||
The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins
|
0538594 |
2009-12-20 | Ponganis, Paul |
|
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 | |||||||
Collaborative Research: Differential Expression of Oxygen-binding Proteins in Antarctic Fishes Affects Nitric Oxide-mediated Pathways of Angiogenesis and Mitochondrial Biogenesis.
|
0437887 |
2009-12-06 | Sidell, Bruce | 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. <br/>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. <br/>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 implicated 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 |