PDF(Pubmed)
Abstract：
Apostasia fujianica belongs to the genus Apostasia and is part of the basal lineage in the phylogenetic tree of the Orchidaceae. Currently, there are only ten reported complete mitochondrial genomes in orchids, which greatly hinders the understanding of mitochondrial evolution in Orchidaceae. Therefore, we assembled and annotated the mitochondrial genome of A. fujianica, which has a length of 573,612 bp and a GC content of 44.5%. We annotated a total of 44 genes, including 30 protein-coding genes, 12 tRNA genes, and two rRNA genes. We also performed relative synonymous codon usage (RSCU) analysis, repeat sequence analysis, intergenomic transfer (IGT) analysis, and Ka/Ks analysis for A. fujianica and conducted RNA editing site analysis on the mitochondrial genomes of eight orchid species. We found that most protein-coding genes are under purifying selection, but nad6 is under positive selection, with a Ka/Ks value of 1.35. During the IGT event in A. fujianica\'s mitogenome, the trnN-GUU, trnD-GUC, trnW-CCA, trnP-UGG, and psaJ genes were identified as having transferred from the plastid to the mitochondrion. Compared to other monocots, the family Orchidaceae appears to have lost the rpl10, rpl14, sdh3, and sdh4 genes. Additionally, to further elucidate the evolutionary relationships among monocots, we constructed a phylogenetic tree based on the complete mitogenomes of monocots. Our study results provide valuable data on the mitogenome of A. fujianica and lay the groundwork for future research on genetic variation, evolutionary relationships, and breeding of Orchidaceae.
摘要：
扶桑属属，是兰科系统发育树中基础谱系的一部分。目前,据报道，兰花中只有10个完整的线粒体基因组，这极大地阻碍了对兰科线粒体进化的理解。因此,我们组装并注释了A.fujianica的线粒体基因组，其长度为573,612bp，GC含量为44.5%。我们共注释了44个基因，包括30个蛋白质编码基因，12个tRNA基因，和两个rRNA基因.我们还进行了相对同义密码子使用（RSCU）分析，重复序列分析，基因组间转移（IGT）分析，并对8种兰花的线粒体基因组进行了RNA编辑位点分析。我们发现大多数蛋白质编码基因都在纯化选择中，但是nad6处于正选择状态，Ka/Ks值为1.35。在福建A.的有丝分裂体的IGT事件期间，trnN-GUU，trnD-GUC,trnW-CCA,trnP-UGG,和psaJ基因被鉴定为已从质体转移到线粒体。与其他单子叶植物相比，兰科似乎失去了rpl10，rpl14，sdh3和sdh4基因。此外,为了进一步阐明单子叶植物之间的进化关系，我们根据单子叶植物的完整有丝分裂基因组构建了一个系统发育树。我们的研究结果提供了有价值的数据，为未来的遗传变异研究奠定了基础。进化关系，和兰科的繁殖。
