Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes
Hepcidin is a small bioactive peptide with dual roles as an antimicrobial peptide and as the principal hormonal regulator of iron homeostasis in human and mouse. Hepcidin homologs of very similar structures are found in lower vertebrates, all comprise ∼20-25 amino acids with eight highly conserved c...
Published in: | Molecular Biology and Evolution |
---|---|
Main Authors: | , , , , , , , , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2008
|
Subjects: | |
Online Access: | http://mbe.oxfordjournals.org/cgi/content/short/msn056v1 https://doi.org/10.1093/molbev/msn056 |
id |
fthighwire:oai:open-archive.highwire.org:molbiolevol:msn056v1 |
---|---|
record_format |
openpolar |
spelling |
fthighwire:oai:open-archive.highwire.org:molbiolevol:msn056v1 2023-05-15T13:40:01+02:00 Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes Qianghua, Xu Christina Cheng, C.-H. Hu, Peng Ye, Hua Chen, Zuozhou Cao, Lixue Chen, Lei Shen, Yu Chen, Liangbiao 2008-02-29 22:10:11.0 text/html http://mbe.oxfordjournals.org/cgi/content/short/msn056v1 https://doi.org/10.1093/molbev/msn056 en eng Oxford University Press http://mbe.oxfordjournals.org/cgi/content/short/msn056v1 http://dx.doi.org/10.1093/molbev/msn056 Copyright (C) 2008, Society for Molecular Biology and Evolution Research Article TEXT 2008 fthighwire https://doi.org/10.1093/molbev/msn056 2013-05-27T15:55:49Z Hepcidin is a small bioactive peptide with dual roles as an antimicrobial peptide and as the principal hormonal regulator of iron homeostasis in human and mouse. Hepcidin homologs of very similar structures are found in lower vertebrates, all comprise ∼20-25 amino acids with eight highly conserved cysteines forming four intramolecular disulfide bonds, giving hepcidin a hairpin structure. Hepcidins are particularly diverse in teleost fishes, which may be related to the diversity of aquatic environments with varying degree of pathogen challenge, oxygenation, and iron concentration, factors known to alter hepcidin expression in mammals. We characterized the diversity of hepcidin genes of the Antarctic notothenioid fishes that are endemic to the world's coldest and most oxygen-rich marine water. Notothenioid fishes have at least four hepcidin variants, in two distinctive structural types. Type I hepcidins comprise three distinct variants that are homologs of the widespread 8-cysteine hepcidins. Type II is a novel 4-cysteine variant and therefore only two possible disulfide bonds, highly expressed in hematopoietic tissues. Analyses of d N / d S substitution rate ratios and Likelihood Ratio Test under site-specific models detected significant signal of positive Darwinian selection on the mature hepcidin coding sequence, suggesting adaptive evolution of notothenioid hepcidins. Genomic PCR and Southern hybridization showed that the novel type II hepcidin occurs exclusively in lineages of the Antarctic notothenioid radiation but not in the basal non-Antarctic taxa, and lineage-specific positive selection was detected on the branch leading to the type II hepcidin clade under Branch-site models, suggesting adaptive evolution of the reduced-cysteine variant in response to the polar environment. We also isolated a structurally distinct 4-cysteine hepcidin from an Antarctic eelpout that is unrelated to the notothenioids but inhabits the same freezing water. Neighbor-Joining analyses of teleost hepcidins showed the eelpout ... Text Antarc* Antarctic HighWire Press (Stanford University) Antarctic The Antarctic Molecular Biology and Evolution 25 6 1099 1112 |
institution |
Open Polar |
collection |
HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Research Article |
spellingShingle |
Research Article Qianghua, Xu Christina Cheng, C.-H. Hu, Peng Ye, Hua Chen, Zuozhou Cao, Lixue Chen, Lei Shen, Yu Chen, Liangbiao Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
topic_facet |
Research Article |
description |
Hepcidin is a small bioactive peptide with dual roles as an antimicrobial peptide and as the principal hormonal regulator of iron homeostasis in human and mouse. Hepcidin homologs of very similar structures are found in lower vertebrates, all comprise ∼20-25 amino acids with eight highly conserved cysteines forming four intramolecular disulfide bonds, giving hepcidin a hairpin structure. Hepcidins are particularly diverse in teleost fishes, which may be related to the diversity of aquatic environments with varying degree of pathogen challenge, oxygenation, and iron concentration, factors known to alter hepcidin expression in mammals. We characterized the diversity of hepcidin genes of the Antarctic notothenioid fishes that are endemic to the world's coldest and most oxygen-rich marine water. Notothenioid fishes have at least four hepcidin variants, in two distinctive structural types. Type I hepcidins comprise three distinct variants that are homologs of the widespread 8-cysteine hepcidins. Type II is a novel 4-cysteine variant and therefore only two possible disulfide bonds, highly expressed in hematopoietic tissues. Analyses of d N / d S substitution rate ratios and Likelihood Ratio Test under site-specific models detected significant signal of positive Darwinian selection on the mature hepcidin coding sequence, suggesting adaptive evolution of notothenioid hepcidins. Genomic PCR and Southern hybridization showed that the novel type II hepcidin occurs exclusively in lineages of the Antarctic notothenioid radiation but not in the basal non-Antarctic taxa, and lineage-specific positive selection was detected on the branch leading to the type II hepcidin clade under Branch-site models, suggesting adaptive evolution of the reduced-cysteine variant in response to the polar environment. We also isolated a structurally distinct 4-cysteine hepcidin from an Antarctic eelpout that is unrelated to the notothenioids but inhabits the same freezing water. Neighbor-Joining analyses of teleost hepcidins showed the eelpout ... |
format |
Text |
author |
Qianghua, Xu Christina Cheng, C.-H. Hu, Peng Ye, Hua Chen, Zuozhou Cao, Lixue Chen, Lei Shen, Yu Chen, Liangbiao |
author_facet |
Qianghua, Xu Christina Cheng, C.-H. Hu, Peng Ye, Hua Chen, Zuozhou Cao, Lixue Chen, Lei Shen, Yu Chen, Liangbiao |
author_sort |
Qianghua, Xu |
title |
Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
title_short |
Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
title_full |
Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
title_fullStr |
Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
title_full_unstemmed |
Adaptive Evolution of Hepcidin Genes in Antarctic Notothenioid Fishes |
title_sort |
adaptive evolution of hepcidin genes in antarctic notothenioid fishes |
publisher |
Oxford University Press |
publishDate |
2008 |
url |
http://mbe.oxfordjournals.org/cgi/content/short/msn056v1 https://doi.org/10.1093/molbev/msn056 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://mbe.oxfordjournals.org/cgi/content/short/msn056v1 http://dx.doi.org/10.1093/molbev/msn056 |
op_rights |
Copyright (C) 2008, Society for Molecular Biology and Evolution |
op_doi |
https://doi.org/10.1093/molbev/msn056 |
container_title |
Molecular Biology and Evolution |
container_volume |
25 |
container_issue |
6 |
container_start_page |
1099 |
op_container_end_page |
1112 |
_version_ |
1766126972152315904 |