Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
School of Biological and Pharmaceutical Engineering, Xinyang Agriculture and Forestry University, Xinyang 464000, China.
Int J Mol Sci. 2018 Nov 28;19(12):3780. doi: 10.3390/ijms19123780.
The order Nymphaeales, consisting of three families with a record of eight genera, has gained significant interest from botanists, probably due to its position as a basal angiosperm. The phylogenetic relationships within the order have been well studied; however, a few controversial nodes still remain in the Nymphaeaceae. The position of the genus and the monophyly of the Nymphaeaceae family remain uncertain. This study adds to the increasing number of the completely sequenced plastid genomes of the Nymphaeales and applies a large chloroplast gene data set in reconstructing the intergeneric relationships within the Nymphaeaceae. Five complete chloroplast genomes were newly generated, including a first for the monotypic genus. Using a set of 66 protein-coding genes from the chloroplast genomes of 17 taxa, the phylogenetic position of was determined and a monophyletic Nymphaeaceae family was obtained with convincing statistical support from both partitioned and unpartitioned data schemes. Although genomic comparative analyses revealed a high degree of synteny among the chloroplast genomes of the ancient angiosperms, key minor variations were evident, particularly in the contraction/expansion of the inverted-repeat regions and in RNA-editing events. Genome structure, and gene content and arrangement were highly conserved among the chloroplast genomes. The intergeneric relationships defined in this study are congruent with those inferred using morphological data.
单子叶植物睡莲目，包含三个科八个属，由于其作为基生被子植物的地位而引起了植物学家的极大兴趣。该目的系统发育关系已得到很好的研究，但在睡莲科中仍存在一些有争议的节点。属的位置和睡莲科的单系性仍然不确定。本研究增加了越来越多的睡莲目完全测序的质体基因组，并应用了大量的质体基因数据集来重建睡莲科内的属间关系。新生成了五个完整的质体基因组，其中包括单型属的第一个基因组。利用来自 17 个分类群的质体基因组中的 66 个蛋白质编码基因，确定了 的系统发育位置，并获得了具有令人信服的统计支持的单系睡莲科家族，无论是分区还是非分区数据方案。尽管基因组比较分析显示古老被子植物的质体基因组之间具有高度的同线性，但明显存在关键的小变异，特别是在反向重复区域的收缩/扩张和 RNA 编辑事件中。质体基因组在基因组结构、基因含量和排列方面高度保守。本研究中定义的属间关系与使用形态数据推断的关系一致。
