Atypically low rate of cytochrome b evolution in the scleractinian coral genus Acropora. Proc Roy Soc, London, Series

Department of Biochemistry and Molecular Biology, James Cook University, Townsville, Australia.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.05). 02/1999; 266(1415):179-83. DOI: 10.1098/rspb.1999.0619
Source: PubMed


Unexpectedly low levels of mitochondrial DNA (mtDNA) cytochrome b sequence divergence are found between species of the scleractinian coral genus Acropora. Comparison of 964 positions of the cytochrome b gene of two out of the three Caribbean Acropora species with seven of their Pacific congeners shows only 0.3-0.8% sequence difference. Species in these biogeographic regions have been evolving independently for at least three million years (since the rise of the Isthmus of Panama) and this geological date is used to estimate nucleotide divergence rates. The results indicate that the Acropora cytochrome b gene is evolving at least 10-20 times slower than the 'standard' vertebrate mtDNA clock and is one of the most slowly evolving animal mitochondrial genes described to date. The possibility is discussed that, unlike higher animals, cnidarians may have a functional mtDNA mismatch repair system.

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Available from: Madeleine van Oppen, Mar 12, 2014
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    • "However, there was almost no sign of a bottleneck in the nuclear microsatellite loci, implying that invariant mtDNA is not likely caused by a bottleneck. Although the mtMutS gene has higher rates of mutation than other octocoral genes (Bilewitch and Degnan, 2011), mtDNA of anthozoans generally evolves very slowly (France et al., 1996; van Oppen et al., 1999), and sometimes mtDNA sequences of corals are identical among different genera or even families (Fukami et al., 2004; Romano and Palumbi, 1996). "
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    • "Mitochondrial DNA is one the most widely used and informative molecular markers in Metazoa; however, the Anthozoan mitochondrial genome evolves unusually slowly, providing little phylogenetic resolution at or below the family or genus level [7,8]. The nuclear ribosomal ITS region (a portion of the ribosomal cistron consisting of two rapidly evolving internal transcribed spacers and the 5.8S gene) is among the most widely used molecular markers for species-level studies in plants [9], fungi [10], and corals [11-29]. "
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    • "Low mitochondrial variation has been noted in previous studies, in which genetic variations in coding regions of coral mtDNA show either no variation (Snell et al. 1998; van Oppen et al. 1999; Chen and Yu 2000; Fukami et al. 2000; Hellberg 2006) or very little variation restricted to nonsynonymous sites (Medina et al. 1999). A more striking pattern of slow evolutionary tempos was observed among three members of the Montastraea annularis complex of only 0.03–0.04% "
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