Seung Chul Shin1, Do Hwan Ahn1,2, Su Jin Kim3, Chul Woo Pyo4, Hyoungseok Lee1, Mi-Kyeong Kim1, Jungeun Lee1, Jong Eun Lee5, H William Detrich III6, John H Postlethwait7, David Edwards8,9, Sung Gu Lee1,2, Jun Hyuck Lee1,2, Hyun Park1,2*
1 Division of Polar Life Sciences, Korea Polar Research Institute, Yeonsu-gu, Incheon 406-840, South Korea
2 Polar Sciences, University of Science & Technology, Yuseong-gu, Daejeon 305-333, South Korea
3 Division of Biotechnology, Korea University, Sungbuk-gu, Seoul 406-840, South Korea
4 Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, D4-100, Seattle, WA 98109-1024, USA
5 DNA Link, Inc, Songpa-gu, Seoul 138-736, South Korea
6 Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, MA 01908, USA
7 Department of Biology, University of Oregon, Eugene, OR 97403, USA
8 Australian Centre for Plant Functional Genomic, School of Agriculture and Food Sciences, University of Queensland, St Lucia, QLD, Australia
9 School of Plant Biology, University of Western Australia, Crawley, WA 6009, Australia
* Corresponding author : Hyun Park
Antarctic fish have adapted to the freezing waters of the Southern Ocean. Representative adaptations to this harsh environment include a constitutive heat shock response and the evolution of an antifreeze protein in the blood. Despite their adaptations to the cold, genome-wide studies have not yet been performed on these fish due to the lack of a sequenced genome. Notothenia coriiceps, the Antarctic bullhead notothen, is an endemic teleost fish with a circumpolar distribution and makes a good model to understand the genomic adaptations to constant sub-zero temperatures.
We provide the draft genome sequence and annotation for N. coriiceps. Comparative genome-wide analysis with other fish genomes shows that mitochondrial proteins and hemoglobin evolved rapidly. Transcriptome analysis of thermal stress responses find alternative response mechanisms for evolution strategies in a cold environment. Loss of the phosphorylation-dependent sumoylation motif in heat shock factor 1 suggests that the heat shock response evolved into a simple and rapid phosphorylation-independent regulatory mechanism. Rapidly evolved hemoglobin and the induction of a heat shock response in the blood may support the efficient supply of oxygen to cold-adapted mitochondria.
Our data and analysis suggest that evolutionary strategies in efficient aerobic cellular respiration are controlled by hemoglobin and mitochondrial proteins, which may be important for the adaptation of Antarctic fish to their environment. The use of genome data from the Antarctic endemic fish provides an invaluable resource providing evidence of evolutionary adaptation and can be applied to other studies of Antarctic fish.