TY - JOUR
T1 - Antarctic blackfin icefish genome reveals adaptations to extreme environments
AU - Kim, Bo Mi
AU - Amores, Angel
AU - Kang, Seunghyun
AU - Ahn, Do Hwan
AU - Kim, Jin Hyoung
AU - Kim, Il Chan
AU - Lee, Jun Hyuck
AU - Lee, Sung Gu
AU - Lee, Hyoungseok
AU - Lee, Jungeun
AU - Kim, Han Woo
AU - Desvignes, Thomas
AU - Batzel, Peter
AU - Sydes, Jason
AU - Titus, Tom
AU - Wilson, Catherine A.
AU - Catchen, Julian M.
AU - Warren, Wesley C.
AU - Schartl, Manfred
AU - Detrich, H. William
AU - Postlethwait, John H.
AU - Park, Hyun
N1 - Publisher Copyright:
© 2019, The Author(s).
PY - 2019/3/1
Y1 - 2019/3/1
N2 - Icefishes (suborder Notothenioidei; family Channichthyidae) are the only vertebrates that lack functional haemoglobin genes and red blood cells. Here, we report a high-quality genome assembly and linkage map for the Antarctic blackfin icefish Chaenocephalus aceratus, highlighting evolved genomic features for its unique physiology. Phylogenomic analysis revealed that Antarctic fish of the teleost suborder Notothenioidei, including icefishes, diverged from the stickleback lineage about 77 million years ago and subsequently evolved cold-adapted phenotypes as the Southern Ocean cooled to sub-zero temperatures. Our results show that genes involved in protection from ice damage, including genes encoding antifreeze glycoprotein and zona pellucida proteins, are highly expanded in the icefish genome. Furthermore, genes that encode enzymes that help to control cellular redox state, including members of the sod3 and nqo1 gene families, are expanded, probably as evolutionary adaptations to the relatively high concentration of oxygen dissolved in cold Antarctic waters. In contrast, some crucial regulators of circadian homeostasis (cry and per genes) are absent from the icefish genome, suggesting compromised control of biological rhythms in the polar light environment. The availability of the icefish genome sequence will accelerate our understanding of adaptation to extreme Antarctic environments.
AB - Icefishes (suborder Notothenioidei; family Channichthyidae) are the only vertebrates that lack functional haemoglobin genes and red blood cells. Here, we report a high-quality genome assembly and linkage map for the Antarctic blackfin icefish Chaenocephalus aceratus, highlighting evolved genomic features for its unique physiology. Phylogenomic analysis revealed that Antarctic fish of the teleost suborder Notothenioidei, including icefishes, diverged from the stickleback lineage about 77 million years ago and subsequently evolved cold-adapted phenotypes as the Southern Ocean cooled to sub-zero temperatures. Our results show that genes involved in protection from ice damage, including genes encoding antifreeze glycoprotein and zona pellucida proteins, are highly expanded in the icefish genome. Furthermore, genes that encode enzymes that help to control cellular redox state, including members of the sod3 and nqo1 gene families, are expanded, probably as evolutionary adaptations to the relatively high concentration of oxygen dissolved in cold Antarctic waters. In contrast, some crucial regulators of circadian homeostasis (cry and per genes) are absent from the icefish genome, suggesting compromised control of biological rhythms in the polar light environment. The availability of the icefish genome sequence will accelerate our understanding of adaptation to extreme Antarctic environments.
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U2 - 10.1038/s41559-019-0812-7
DO - 10.1038/s41559-019-0812-7
M3 - Article
C2 - 30804520
AN - SCOPUS:85062062721
SN - 2397-334X
VL - 3
SP - 469
EP - 478
JO - Nature Ecology and Evolution
JF - Nature Ecology and Evolution
IS - 3
ER -