Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA.
Mol Ecol Resour. 2013 May;13(3):347-53. doi: 10.1111/1755-0998.12066. Epub 2013 Jan 25.
Resolving the evolutionary history of rapidly diversifying lineages like the Lake Malawi Cichlid Flock demands powerful phylogenetic tools. Although this clade of over 500 species of fish likely diversified in less than two million years, the availability of extensive sequence data sets, such as complete mitochondrial genomes, could help resolve evolutionary patterns in this group. Using a large number of newly developed primers, we generated whole mitochondrial genome sequences for 14 Lake Malawi cichlids. We compared sequence divergence across protein-coding regions of the mitochondrial genome and also compared divergence in the mitochondrial loci to divergence at two nuclear protein-coding loci, Mitfb and Dlx2. Despite the widespread sharing of haplotypes of identical sequences at individual loci, the combined use of all protein-coding mitochondrial loci provided a bifurcating phylogenetic hypothesis for the exemplars of major lineages within the Lake Malawi cichlid radiation. The primers presented here could have substantial utility for evolutionary analyses of mitochondrial evolution and hybridization within this diverse clade.
解析如马拉维湖慈鲷鱼群这般快速分化的谱系的进化历史需要强有力的系统发育工具。尽管这个拥有超过 500 个种鱼类的类群可能在不到两百万年的时间里多样化,但大量序列数据集(如完整的线粒体基因组)的可用性可以帮助解析该群体的进化模式。利用大量新开发的引物,我们为 14 种马拉维湖慈鲷鱼生成了完整的线粒体基因组序列。我们比较了线粒体基因组蛋白编码区的序列分歧,也比较了线粒体基因座的分歧与两个核蛋白编码基因座 Mitfb 和 Dlx2 的分歧。尽管在单个基因座上存在广泛共享相同序列的单倍型,但所有蛋白编码线粒体基因座的联合使用为马拉维湖慈鲷辐射内主要谱系的典型代表提供了一个分叉的系统发育假说。这里提出的引物对于这个多样化类群中的线粒体进化和杂交的进化分析可能具有重要的应用价值。