France SC, Rosel PE, Agenbroad JE, Mullineaux LS, Kocher TD.. DNA sequence variation of mitochondrial large-subunit rRNA provides support for a two-subclass organization of the Anthozoa (Cnidaria). Mol Mar Biol Biotechnol 5: 15-28

Department of Zoology, University of New Hampshire, Durham 03824, USA.
Molecular marine biology and biotechnology 04/1996; 5(1):15-28.
Source: PubMed


We have sequenced a portion of the mitochondrial 16S rRNA gene from 29 species of Anthozoa, representing six orders of the subclasses Ceriantipatharia, Hexacorallia, and Octocorallia, with the focus on deep-seamount corals (> 500-m depth). We have detected significant length variation in the gene, with homologous gene fragments ranging from 545 bp in a shallow-water scleractinian coral to 911 bp in a deep-sea antipatharian black coral. The aligned sequences were divided into five regions: three high-identity sequence blocks (HSBs) and two highly variable blocks of insertions/deletions (INDELs). Most of the length variation among species occurred as varying numbers of nucleotides in the two INDELs. Little or no intraspecific sequence variation was detected over spatial scales of up to approximately 150 km. Interspecific sequence variation was lowest among the octocorals and greatest among the ceriantipatharians. Our data indicate that the orders Ceriantharia and Antipatharia are highly divergent, and a phylogenetic reconstruction provides support for the two-subclass system of the class Anthozoa (Hexacorallia and Octocorallia).

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Available from: Thomas Kocher, Feb 05, 2015
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    • "Although Reimer et al. (2004) and Sinniger et al. (2008) have shown that some species of the hexacorallian order Zoantharia can be distinguished by analyses of COI, generally for octocorals, COI sequences have low variability among species and genera, and this marker is considered more suitable for investigating higher-level (genus and higher) phylogenies. Msh1 is a mitochondrial region specific to octocorals and is considered to be a homolog of the prokaryote MutS gene (France et al., 1996; Berntson et al., 1999). Msh1 shows much more variability than COI, and is appropriate for more detailed phylogenetic investigations in many groups of octocorals (Sánchez et al., 2003b; Wirshing et al., 2005; McFadden et al., 2006b). "
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    • "ertions and / or deletions suggesting that this region may have good phylogenetic information . Even though we did find this variable region within the 16S alignment , it is very small ( 38 bp ) , and an independent phylogenetic analysis for this small region only supports 2 clades ( support values >0 . 8 for BI ) . Using a larger sample size than France et al . ( 1996 ) , and obtaining specimens from different genera and different localities , mainly around New Zealand but also including the North Pacific , Chile , the Atlantic and the Mediterranean , we expected to see larger variable regions within the 16S alignment that showed genetic and geographic var - iation , but we did not . Higher variation"
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