Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration
Summer storms along the Antarctic Peninsula can cause microhabitats of the terrestrial midge Belgica antarctica to become periodically inundated with seawater from tidal spray. As microhabitats dry, larvae may be exposed to increasing concentrations of seawater. Alternatively, as a result of melting...
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fthighwire:oai:open-archive.highwire.org:jexbio:212/17/2864 2023-05-15T13:45:49+02:00 Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration Elnitsky, Michael A. Benoit, Joshua B. Lopez-Martinez, Giancarlo Denlinger, David L. Lee, Richard E. 2009-09-01 00:00:00.0 text/html http://jeb.biologists.org/cgi/content/short/212/17/2864 https://doi.org/10.1242/jeb.034173 en eng Company of Biologists http://jeb.biologists.org/cgi/content/short/212/17/2864 http://dx.doi.org/10.1242/jeb.034173 Copyright (C) 2009, Company of Biologists Research Article TEXT 2009 fthighwire https://doi.org/10.1242/jeb.034173 2013-04-02T07:37:34Z Summer storms along the Antarctic Peninsula can cause microhabitats of the terrestrial midge Belgica antarctica to become periodically inundated with seawater from tidal spray. As microhabitats dry, larvae may be exposed to increasing concentrations of seawater. Alternatively, as a result of melting snow or following rain, larvae may be immersed in freshwater for extended periods. The present study assessed the tolerance and physiological response of B. antarctica larvae to salinity exposure, and examined the effect of seawater acclimation on their subsequent tolerance of freezing, dehydration and heat shock. Midge larvae tolerated extended exposure to hyperosmotic seawater; nearly 50% of larvae survived a 10-day exposure to 1000 mOsm kg–1 seawater and ∼25% of larvae survived 6 days in 2000 mOsm kg–1 seawater. Exposure to seawater drastically reduced larval body water content and increased hemolymph osmolality. By contrast, immersion in freshwater did not affect water content or hemolymph osmolality. Hyperosmotic seawater exposure, and the accompanying osmotic dehydration, resulted in a significant correlation between the rate of oxygen consumption and larval water content and induced the de novo synthesis and accumulation of several organic osmolytes. A 3-day exposure of larvae to hyperosmotic seawater increased freezing tolerance relative to freshwater-acclimated larvae. Even after rehydration, the freezing survival of larvae acclimated to seawater was greater than freshwater-acclimated larvae. Additionally, seawater exposure increased the subsequent tolerance of larvae to dehydration. Our results further illustrate the similarities between these related, yet distinct, forms of osmotic stress and add to the suite of physiological responses used by larvae to enhance survival in the harsh and unpredictable Antarctic environment. Text Antarc* Antarctic Antarctic midge Antarctic Peninsula Antarctica Belgica antarctica HighWire Press (Stanford University) Antarctic The Antarctic Antarctic Peninsula Journal of Experimental Biology 212 17 2864 2871 |
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English |
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Research Article |
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Research Article Elnitsky, Michael A. Benoit, Joshua B. Lopez-Martinez, Giancarlo Denlinger, David L. Lee, Richard E. Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
topic_facet |
Research Article |
description |
Summer storms along the Antarctic Peninsula can cause microhabitats of the terrestrial midge Belgica antarctica to become periodically inundated with seawater from tidal spray. As microhabitats dry, larvae may be exposed to increasing concentrations of seawater. Alternatively, as a result of melting snow or following rain, larvae may be immersed in freshwater for extended periods. The present study assessed the tolerance and physiological response of B. antarctica larvae to salinity exposure, and examined the effect of seawater acclimation on their subsequent tolerance of freezing, dehydration and heat shock. Midge larvae tolerated extended exposure to hyperosmotic seawater; nearly 50% of larvae survived a 10-day exposure to 1000 mOsm kg–1 seawater and ∼25% of larvae survived 6 days in 2000 mOsm kg–1 seawater. Exposure to seawater drastically reduced larval body water content and increased hemolymph osmolality. By contrast, immersion in freshwater did not affect water content or hemolymph osmolality. Hyperosmotic seawater exposure, and the accompanying osmotic dehydration, resulted in a significant correlation between the rate of oxygen consumption and larval water content and induced the de novo synthesis and accumulation of several organic osmolytes. A 3-day exposure of larvae to hyperosmotic seawater increased freezing tolerance relative to freshwater-acclimated larvae. Even after rehydration, the freezing survival of larvae acclimated to seawater was greater than freshwater-acclimated larvae. Additionally, seawater exposure increased the subsequent tolerance of larvae to dehydration. Our results further illustrate the similarities between these related, yet distinct, forms of osmotic stress and add to the suite of physiological responses used by larvae to enhance survival in the harsh and unpredictable Antarctic environment. |
format |
Text |
author |
Elnitsky, Michael A. Benoit, Joshua B. Lopez-Martinez, Giancarlo Denlinger, David L. Lee, Richard E. |
author_facet |
Elnitsky, Michael A. Benoit, Joshua B. Lopez-Martinez, Giancarlo Denlinger, David L. Lee, Richard E. |
author_sort |
Elnitsky, Michael A. |
title |
Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
title_short |
Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
title_full |
Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
title_fullStr |
Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
title_full_unstemmed |
Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
title_sort |
osmoregulation and salinity tolerance in the antarctic midge, belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration |
publisher |
Company of Biologists |
publishDate |
2009 |
url |
http://jeb.biologists.org/cgi/content/short/212/17/2864 https://doi.org/10.1242/jeb.034173 |
geographic |
Antarctic The Antarctic Antarctic Peninsula |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula |
genre |
Antarc* Antarctic Antarctic midge Antarctic Peninsula Antarctica Belgica antarctica |
genre_facet |
Antarc* Antarctic Antarctic midge Antarctic Peninsula Antarctica Belgica antarctica |
op_relation |
http://jeb.biologists.org/cgi/content/short/212/17/2864 http://dx.doi.org/10.1242/jeb.034173 |
op_rights |
Copyright (C) 2009, Company of Biologists |
op_doi |
https://doi.org/10.1242/jeb.034173 |
container_title |
Journal of Experimental Biology |
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212 |
container_issue |
17 |
container_start_page |
2864 |
op_container_end_page |
2871 |
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1766231278223360000 |