Muscle metabolism and growth in Antarctic fishes ( suborder Notothenioidei ): evolution in a cold environment
The radiation of notothenioid fishes (order Perciformes) in the Southern Ocean provides a model system for investigating evolution and adaptation to a low temperature environment. The Notothenioid fishes comprising eight families, 43 genera and 122 species dominate the fish fauna in Antarctica. The...
| Published in: | Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology |
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| Main Author: | |
| Format: | Other/Unknown Material |
| Language: | English |
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2003
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| Online Access: | https://research-portal.st-andrews.ac.uk/en/researchoutput/muscle-metabolism-and-growth-in-antarctic-fishes--suborder-notothenioidei--evolution-in-a-cold-environment(8abf74ab-a748-447d-88df-170602f753a5).html https://doi.org/10.1016/S1096-4959(03)00258-6 http://www.scopus.com/inward/record.url?scp=0345096660&partnerID=8YFLogxK |
| Summary: | The radiation of notothenioid fishes (order Perciformes) in the Southern Ocean provides a model system for investigating evolution and adaptation to a low temperature environment. The Notothenioid fishes comprising eight families, 43 genera and 122 species dominate the fish fauna in Antarctica. The diversification of the clade probably began 15-20 million years ago after the formation of the Antarctic Polar Front. The radiation was, therefore, associated with climatic cooling down to the present day temperature of -1.86 degreesC. Origins and Evolution of the Antarctic Biota Geological Society Special Publication No. 47, Geological Society of London. pp. 253-268). The success of the group has been closely linked with the evolution of glycopeptide and peptide antifreezes, which are amongst the most abundant proteins in blood and interstitial fluid. The radiation of the clade has been associated with disaptation (evolutionary loss of function) and recovery. For example, it is thought that the icefishes (Channichyidae) lost haemoglobin through a single mutational event leading to the deletion of the entire P-globin gene and the 5' end of the linked (x-globin gene, resulting in compensatory adaptations of the cardiovascular system. Phylogenetically based statistical methods also indicate a progressive and dramatic reduction in the number of skeletal muscle fibres (FNmax) at the end of the recruitment phase of growth in basal compared to derived families. The reduction in FNmax is associated with a compensatory increase in the maximum fibre diameter, which can reach 100 mum in slow and 600 mum in fast muscle fibres. At -1 to 0 degreesC, the oxygen consumption of isolated mitochondria per mg mitochondrial protein shows no evidence of up-regulation relative to mitochondria from temperate and tropical Perciform. fishes. The mitochondria content of slow muscle fibres in Antarctic notothenioids is towards the upper end of the range reported for teleosts with similar lifestyles, reaching 50% in Channichthyids. High ... |
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