Fairy Lake Botanical Garden & Chinese Academy of Sciences, Shenzhen, 518004, China.
BGI-Shenzhen, Shenzhen, 518120, China.
Nat Commun. 2019 Apr 2;10(1):1485. doi: 10.1038/s41467-019-09454-w.
Mosses are a highly diverse lineage of land plants, whose diversification, spanning at least 400 million years, remains phylogenetically ambiguous due to the lack of fossils, massive early extinctions, late radiations, limited morphological variation, and conflicting signal among previously used markers. Here, we present phylogenetic reconstructions based on complete organellar exomes and a comparable set of nuclear genes for this major lineage of land plants. Our analysis of 142 species representing 29 of the 30 moss orders reveals that relative average rates of non-synonymous substitutions in nuclear versus plastid genes are much higher in mosses than in seed plants, consistent with the emerging concept of evolutionary dynamism in mosses. Our results highlight the evolutionary significance of taxa with reduced morphologies, shed light on the relative tempo and mechanisms underlying major cladogenic events, and suggest hypotheses for the relationships and delineation of moss orders.
藓类植物是陆地植物中高度多样化的谱系，由于缺乏化石、大规模早期灭绝、晚期辐射、形态变异有限以及先前使用的标记之间存在冲突信号，其多样化跨越了至少 4 亿年，但在系统发育上仍然存在模糊性。在这里，我们基于完整的细胞器外显子组和一组可比的核基因，为这个主要的陆地植物谱系重建了系统发育。我们对代表 30 个藓类植物目中的 29 个目的 142 个物种的分析表明，与种子植物相比，核基因与质体基因中非同义替换的相对平均速率在藓类植物中要高得多，这与藓类植物进化活力的新兴概念一致。我们的研究结果突出了形态减少的类群的进化意义，揭示了主要分支事件背后的相对时温和机制，并为藓类植物目的关系和划定提出了假设。
