Adaptation of Antarctic Icefish Vision to Extreme Environments
Abstract Extreme environments, such as Antarctic habitats, present major challenges for many biological processes. Antarctic icefishes (Crynotothenioidea) represent a compelling system to investigate the molecular basis of adaptation to cold temperatures. Here, we explore how the sub-zero habitats o...
Published in: | Molecular Biology and Evolution |
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Oxford University Press (OUP)
2023
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Online Access: | http://dx.doi.org/10.1093/molbev/msad030 https://academic.oup.com/mbe/advance-article-pdf/doi/10.1093/molbev/msad030/49157101/msad030.pdf https://academic.oup.com/mbe/article-pdf/40/4/msad030/50388900/msad030.pdf |
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croxfordunivpr:10.1093/molbev/msad030 2024-05-19T07:31:49+00:00 Adaptation of Antarctic Icefish Vision to Extreme Environments Castiglione, Gianni M Hauser, Frances E Van Nynatten, Alexander Chang, Belinda S W Yang, Guang 2023 http://dx.doi.org/10.1093/molbev/msad030 https://academic.oup.com/mbe/advance-article-pdf/doi/10.1093/molbev/msad030/49157101/msad030.pdf https://academic.oup.com/mbe/article-pdf/40/4/msad030/50388900/msad030.pdf en eng Oxford University Press (OUP) https://creativecommons.org/licenses/by-nc/4.0/ Molecular Biology and Evolution volume 40, issue 4 ISSN 0737-4038 1537-1719 journal-article 2023 croxfordunivpr https://doi.org/10.1093/molbev/msad030 2024-05-02T09:30:09Z Abstract Extreme environments, such as Antarctic habitats, present major challenges for many biological processes. Antarctic icefishes (Crynotothenioidea) represent a compelling system to investigate the molecular basis of adaptation to cold temperatures. Here, we explore how the sub-zero habitats of Antarctic icefishes have impacted rhodopsin (RH1) function, the temperature-sensitive dim-light visual pigment found in rod photoreceptors. Using likelihood models and ancestral reconstruction, we find that accelerated evolutionary rates in icefish RH1 underlie unique amino acid mutations absent from other deep-dwelling fishes, introduced before (S160A) and during (V259M) the onset of modern polar conditions. Functional assays reveal that these mutations red-shift rhodopsin spectral absorbance, consistent with spectral irradiance under sea ice. These mutations also lower the activation energy associated with retinal release of the light-activated RH1, and accelerate its return to the dark state, likely compensating for a cold-induced decrease in kinetic rates. These are adaptations in key properties of rhodopsin that mediate rod sensitivity and visual performance in the cold dark seas of the Antarctic. Article in Journal/Newspaper Antarc* Antarctic Icefish Sea ice Oxford University Press Molecular Biology and Evolution |
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Open Polar |
collection |
Oxford University Press |
op_collection_id |
croxfordunivpr |
language |
English |
description |
Abstract Extreme environments, such as Antarctic habitats, present major challenges for many biological processes. Antarctic icefishes (Crynotothenioidea) represent a compelling system to investigate the molecular basis of adaptation to cold temperatures. Here, we explore how the sub-zero habitats of Antarctic icefishes have impacted rhodopsin (RH1) function, the temperature-sensitive dim-light visual pigment found in rod photoreceptors. Using likelihood models and ancestral reconstruction, we find that accelerated evolutionary rates in icefish RH1 underlie unique amino acid mutations absent from other deep-dwelling fishes, introduced before (S160A) and during (V259M) the onset of modern polar conditions. Functional assays reveal that these mutations red-shift rhodopsin spectral absorbance, consistent with spectral irradiance under sea ice. These mutations also lower the activation energy associated with retinal release of the light-activated RH1, and accelerate its return to the dark state, likely compensating for a cold-induced decrease in kinetic rates. These are adaptations in key properties of rhodopsin that mediate rod sensitivity and visual performance in the cold dark seas of the Antarctic. |
author2 |
Yang, Guang |
format |
Article in Journal/Newspaper |
author |
Castiglione, Gianni M Hauser, Frances E Van Nynatten, Alexander Chang, Belinda S W |
spellingShingle |
Castiglione, Gianni M Hauser, Frances E Van Nynatten, Alexander Chang, Belinda S W Adaptation of Antarctic Icefish Vision to Extreme Environments |
author_facet |
Castiglione, Gianni M Hauser, Frances E Van Nynatten, Alexander Chang, Belinda S W |
author_sort |
Castiglione, Gianni M |
title |
Adaptation of Antarctic Icefish Vision to Extreme Environments |
title_short |
Adaptation of Antarctic Icefish Vision to Extreme Environments |
title_full |
Adaptation of Antarctic Icefish Vision to Extreme Environments |
title_fullStr |
Adaptation of Antarctic Icefish Vision to Extreme Environments |
title_full_unstemmed |
Adaptation of Antarctic Icefish Vision to Extreme Environments |
title_sort |
adaptation of antarctic icefish vision to extreme environments |
publisher |
Oxford University Press (OUP) |
publishDate |
2023 |
url |
http://dx.doi.org/10.1093/molbev/msad030 https://academic.oup.com/mbe/advance-article-pdf/doi/10.1093/molbev/msad030/49157101/msad030.pdf https://academic.oup.com/mbe/article-pdf/40/4/msad030/50388900/msad030.pdf |
genre |
Antarc* Antarctic Icefish Sea ice |
genre_facet |
Antarc* Antarctic Icefish Sea ice |
op_source |
Molecular Biology and Evolution volume 40, issue 4 ISSN 0737-4038 1537-1719 |
op_rights |
https://creativecommons.org/licenses/by-nc/4.0/ |
op_doi |
https://doi.org/10.1093/molbev/msad030 |
container_title |
Molecular Biology and Evolution |
_version_ |
1799469708360024064 |