Key Laboratory of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China.
Genes (Basel). 2022 Oct 4;13(10):1791. doi: 10.3390/genes13101791.
The extreme diversity and complexity of angiosperms is well known. Despite the fact that parasitic plants are angiosperms, little is known about parasitic plant mitogenomic diversity, complexity, and evolution. In this study, we obtained and characterized the mitogenomes of three species (holoparasitic plants) from China to compare the repeats, segment duplication and multi-copy protein-coding genes (PCGs), to clarify the phylogenetic and evolution relationship within the order, and to identify the mitochondrial plastid insertions (MTPT) in mitogenomes. The results showed that the mitogenome sizes of the three species ranged from 1,708,661 to 3,978,341 bp. The species genome encodes 75-126 genes, including 37-65 PCGs, 31-58 tRNA genes and 3-5 rRNA genes. Compared with other and parasitic species, the species showed extremely high rates of multi-copy PCGs, ranging from 0.13 to 0.58 percent of the total number of PCGs. In addition, 37-133 Simple Sequence Repeat (SSRs) were found in these three mitogenomes, the majority of which were the mononucleotides Adenine/Thymine. The interspersed repeats contained forward and palindromic repeats. Furthermore, the segment-duplication sequence size ranged from 199,584 to 2,142,551 bp, accounting for 24.9%, 11.7% and 53.9% of the , and mitogenome, respectively. Furthermore, the Ka/Ks analysis suggested that the 4, , and were probably positively selected during evolution. The plastome suggested the presence of MTPT. Moreover, 6-12 tRNA, 9-15 PCGs fragments and 3 rRNA gene fragments in the mitogenomes were found in the MTPT regions. This work reports the species mitogenome for the first time, which will be invaluable for study the mitogenome evolution of family.
被子植物的多样性和复杂性是众所周知的。尽管寄生植物是被子植物，但对寄生植物线粒体基因组的多样性、复杂性和进化知之甚少。在这项研究中，我们从中国获得并鉴定了三个物种（全寄生植物）的线粒体基因组，以比较重复序列、片段重复和多拷贝蛋白编码基因（PCGs），阐明在目内的系统发育和进化关系，并鉴定线粒体质体插入（MTPT）在 线粒体基因组中。结果表明，三种 物种的线粒体基因组大小范围为 1,708,661 至 3,978,341bp。 物种基因组编码 75-126 个基因，包括 37-65 个 PCGs、31-58 个 tRNA 基因和 3-5 个 rRNA 基因。与其他 目和寄生物种相比， 物种的多拷贝 PCGs 率极高，范围从总 PCGs 数的 0.13%到 0.58%。此外，在这三个线粒体基因组中发现了 37-133 个简单序列重复（SSR），其中大多数是单核苷酸腺嘌呤/胸腺嘧啶。散布重复序列包含正向和回文重复序列。此外，片段重复序列的大小范围为 199,584 至 2,142,551bp，分别占 目、 目和 目的线粒体基因组的 24.9%、11.7%和 53.9%。此外，Ka/Ks 分析表明，在 目进化过程中，4、 、 和 可能受到正选择。质体暗示存在 MTPT。此外，在 MTPT 区域发现了 6-12 个 tRNA、9-15 个 PCGs 片段和 3 个 rRNA 基因片段。这项工作首次报道了 物种的线粒体基因组，这对于研究 科的线粒体基因组进化将是非常宝贵的。
