文章基本信息

标题：Chloroplast phylogenomic analyses reveal the deepest-branching lineage of the Chlorophyta, Palmophyllophyceae class. nov.
本地全文：下载
作者：Frederik Leliaert ; Ana Tronholm ; Claude Lemieux 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2016
卷号：6
期号：1
DOI：10.1038/srep25367
语种：English
出版社：Springer Nature
摘要：The green plants (Viridiplantae) are an ancient group of eukaryotes comprising two main clades: the Chlorophyta, which includes a wide diversity of green algae, and the Streptophyta, which consists of freshwater green algae and the land plants. The early-diverging lineages of the Viridiplantae comprise unicellular algae, and multicellularity has evolved independently in the two clades. Recent molecular data have revealed an unrecognized early-diverging lineage of green plants, the Palmophyllales, with a unique form of multicellularity, and typically found in deep water. The phylogenetic position of this enigmatic group, however, remained uncertain. Here we elucidate the evolutionary affinity of the Palmophyllales using chloroplast genomic, and nuclear rDNA data. Phylogenetic analyses firmly place the palmophyllalean Verdigellas peltata along with species of Prasinococcales (prasinophyte clade VI) in the deepest-branching clade of the Chlorophyta. The small, compact and intronless chloroplast genome (cpDNA) of V. peltata shows striking similarities in gene content and organization with the cpDNAs of Prasinococcales and the streptophyte Mesostigma viride, indicating that cpDNA architecture has been extremely well conserved in these deep-branching lineages of green plants. The phylogenetic distinctness of the Palmophyllales-Prasinococcales clade, characterized by unique ultrastructural features, warrants recognition of a new class of green plants, Palmophyllophyceae class. nov.