Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view
A cause and effect understanding of thermal limitation and adaptation at various levels of biological organization is crucial in the elaboration of how the Antarctic climate has shaped the functional properties of extant Antarctic fauna. At the same time, this understanding requires an integrative v...
Published in: | Philosophical Transactions of the Royal Society B: Biological Sciences |
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crroyalsociety:10.1098/rstb.2006.1947 2024-06-23T07:46:44+00:00 Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view Pörtner, Hans O Peck, Lloyd Somero, George 2007 http://dx.doi.org/10.1098/rstb.2006.1947 https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2006.1947 https://royalsocietypublishing.org/doi/full-xml/10.1098/rstb.2006.1947 en eng The Royal Society https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ Philosophical Transactions of the Royal Society B: Biological Sciences volume 362, issue 1488, page 2233-2258 ISSN 0962-8436 1471-2970 journal-article 2007 crroyalsociety https://doi.org/10.1098/rstb.2006.1947 2024-06-10T04:15:12Z A cause and effect understanding of thermal limitation and adaptation at various levels of biological organization is crucial in the elaboration of how the Antarctic climate has shaped the functional properties of extant Antarctic fauna. At the same time, this understanding requires an integrative view of how the various levels of biological organization may be intertwined. At all levels analysed, the functional specialization to permanently low temperatures implies reduced tolerance of high temperatures, as a trade-off. Maintenance of membrane fluidity, enzyme kinetic properties ( K m and k cat ) and protein structural flexibility in the cold supports metabolic flux and regulation as well as cellular functioning overall. Gene expression patterns and, even more so, loss of genetic information, especially for myoglobin (Mb) and haemoglobin (Hb) in notothenioid fishes, reflect the specialization of Antarctic organisms to a narrow range of low temperatures. The loss of Mb and Hb in icefish, together with enhanced lipid membrane densities (e.g. higher concentrations of mitochondria), becomes explicable by the exploitation of high oxygen solubility at low metabolic rates in the cold, where an enhanced fraction of oxygen supply occurs through diffusive oxygen flux. Conversely, limited oxygen supply to tissues upon warming is an early cause of functional limitation. Low standard metabolic rates may be linked to extreme stenothermy. The evolutionary forces causing low metabolic rates as a uniform character of life in Antarctic ectothermal animals may be linked to the requirement for high energetic efficiency as required to support higher organismic functioning in the cold. This requirement may result from partial compensation for the thermal limitation of growth, while other functions like hatching, development, reproduction and ageing are largely delayed. As a perspective, the integrative approach suggests that the patterns of oxygen- and capacity-limited thermal tolerance are linked, on one hand, with the capacity and ... Article in Journal/Newspaper Antarc* Antarctic Icefish The Royal Society Antarctic The Antarctic Philosophical Transactions of the Royal Society B: Biological Sciences 362 1488 2233 2258 |
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The Royal Society |
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crroyalsociety |
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English |
description |
A cause and effect understanding of thermal limitation and adaptation at various levels of biological organization is crucial in the elaboration of how the Antarctic climate has shaped the functional properties of extant Antarctic fauna. At the same time, this understanding requires an integrative view of how the various levels of biological organization may be intertwined. At all levels analysed, the functional specialization to permanently low temperatures implies reduced tolerance of high temperatures, as a trade-off. Maintenance of membrane fluidity, enzyme kinetic properties ( K m and k cat ) and protein structural flexibility in the cold supports metabolic flux and regulation as well as cellular functioning overall. Gene expression patterns and, even more so, loss of genetic information, especially for myoglobin (Mb) and haemoglobin (Hb) in notothenioid fishes, reflect the specialization of Antarctic organisms to a narrow range of low temperatures. The loss of Mb and Hb in icefish, together with enhanced lipid membrane densities (e.g. higher concentrations of mitochondria), becomes explicable by the exploitation of high oxygen solubility at low metabolic rates in the cold, where an enhanced fraction of oxygen supply occurs through diffusive oxygen flux. Conversely, limited oxygen supply to tissues upon warming is an early cause of functional limitation. Low standard metabolic rates may be linked to extreme stenothermy. The evolutionary forces causing low metabolic rates as a uniform character of life in Antarctic ectothermal animals may be linked to the requirement for high energetic efficiency as required to support higher organismic functioning in the cold. This requirement may result from partial compensation for the thermal limitation of growth, while other functions like hatching, development, reproduction and ageing are largely delayed. As a perspective, the integrative approach suggests that the patterns of oxygen- and capacity-limited thermal tolerance are linked, on one hand, with the capacity and ... |
format |
Article in Journal/Newspaper |
author |
Pörtner, Hans O Peck, Lloyd Somero, George |
spellingShingle |
Pörtner, Hans O Peck, Lloyd Somero, George Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
author_facet |
Pörtner, Hans O Peck, Lloyd Somero, George |
author_sort |
Pörtner, Hans O |
title |
Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
title_short |
Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
title_full |
Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
title_fullStr |
Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
title_full_unstemmed |
Thermal limits and adaptation in marine Antarctic ectotherms: an integrative view |
title_sort |
thermal limits and adaptation in marine antarctic ectotherms: an integrative view |
publisher |
The Royal Society |
publishDate |
2007 |
url |
http://dx.doi.org/10.1098/rstb.2006.1947 https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2006.1947 https://royalsocietypublishing.org/doi/full-xml/10.1098/rstb.2006.1947 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Icefish |
genre_facet |
Antarc* Antarctic Icefish |
op_source |
Philosophical Transactions of the Royal Society B: Biological Sciences volume 362, issue 1488, page 2233-2258 ISSN 0962-8436 1471-2970 |
op_rights |
https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ |
op_doi |
https://doi.org/10.1098/rstb.2006.1947 |
container_title |
Philosophical Transactions of the Royal Society B: Biological Sciences |
container_volume |
362 |
container_issue |
1488 |
container_start_page |
2233 |
op_container_end_page |
2258 |
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1802647889330044928 |