Institute of Ecology and Evolutionary Biology, National Taiwan University, 1 Roosevelt Road, Sec. 4, Taipei 10617, Taiwan.
Mol Phylogenet Evol. 2011 Jun;59(3):556-66. doi: 10.1016/j.ympev.2011.03.010. Epub 2011 Mar 21.
MatK, the only maturase gene in the land plant plastid genome, is a very popular phylogenetic marker that has been extensively applied in reconstructing angiosperm phylogeny. However, the use of matK in fern phylogeny is largely unknown, due to difficulties with amplification: ferns have lost the flanking trnK exons, typically the region used for designing stable priming sites. We developed primers that are either universal or lineage-specific that successfully amplify matK across all fern families. To evaluate whether matK is as powerful a phylogenetic marker in ferns as in angiosperms, we compared its sequence characteristics and phylogenetic performance to those of rbcL and atpA. Among these three genes, matK has the highest variability and substitution evenness, yet shows the least homoplasy. Most importantly, applying matK in fern phylogenetics better resolved relationships among families, especially within eupolypods I and II. Here we demonstrate the power of matK for fern phylogenetic reconstruction, as well as provide primers and extensive sequence data that will greatly facilitate future evolutionary studies of ferns.
MatK 是陆地植物质体基因组中唯一的成熟酶基因，是一种非常流行的系统发育标记物，广泛应用于重建被子植物系统发育。然而，由于扩增困难，MatK 在蕨类植物系统发育中的应用还知之甚少：蕨类植物失去了侧翼 trnK 外显子，通常是用于设计稳定引物结合位点的区域。我们开发了通用或谱系特异性的引物，可以成功地在所有蕨类植物家族中扩增 MatK。为了评估 MatK 在蕨类植物中的系统发育标记能力是否与被子植物一样强大，我们将其序列特征和系统发育表现与 rbcL 和 atpA 进行了比较。在这三个基因中，MatK 的变异性和替换均匀性最高，但同质性最低。最重要的是，在蕨类植物系统发育学中应用 MatK 可以更好地解决科之间的关系，特别是在真蕨类植物 I 和 II 中。在这里，我们展示了 MatK 在蕨类植物系统发育重建中的强大功能，并提供了引物和广泛的序列数据，这将极大地促进蕨类植物的未来进化研究。
