College of Landscape Architecture, Nanjing Forestry University, Nanjing 210037, China.
Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
Int J Mol Sci. 2023 Aug 22;24(17):13044. doi: 10.3390/ijms241713044.
L. (Nyctaginaceae) is a South American native woody flowering shrub of high ornamental, economic, and medicinal value which is susceptible to cold damage. We sequenced the complete chloroplast (cp) genome of and , two morphologically similar species differing in cold resistance. Both genomes showed a typical quadripartite structure consisting of one large single-copy region, one small single-copy region, and two inverted repeat regions. The cp genome size of and was 154,520 and 154,542 bp, respectively, with 131 genes, including 86 protein-coding, 37 transfer RNA, and 8 ribosomal RNA genes. In addition, the genomes contained 270 and 271 simple sequence repeats, respectively, with mononucleotide repeats being the most abundant. Eight highly variable sites (, , , , , , , and ) with high nucleotide diversity were identified as potential molecular markers. Phylogenetic analysis revealed a close relationship between and . These findings not only contribute to understanding the mechanism by which the cp genome responds to low-temperature stress in and elucidating the evolutionary characteristics and phylogenetic relationships among species, but also provide important evidence for the accurate identification and breeding of superior cold-tolerant cultivars.
李氏木（Nyctaginaceae）是一种原产于南美洲的木本开花灌木，具有很高的观赏、经济和药用价值，但易受低温伤害。我们对李氏木的两个形态相似但抗寒性不同的种进行了完整叶绿体（cp）基因组测序。两个基因组均表现出典型的四分体结构，由一个大单拷贝区、一个小单拷贝区和两个反向重复区组成。和 的 cp 基因组大小分别为 154520 和 154542 bp，包含 131 个基因，包括 86 个蛋白编码基因、37 个转移 RNA 基因和 8 个核糖体 RNA 基因。此外，基因组分别含有 270 和 271 个简单重复序列，其中单核苷酸重复最为丰富。鉴定出 8 个具有高核苷酸多样性的高度可变位点（、、、、、、和），可作为潜在的分子标记。系统发育分析表明与亲缘关系密切。这些发现不仅有助于了解 cp 基因组对低温胁迫的响应机制，阐明李氏木种间的进化特征和系统发育关系，而且为准确鉴定和培育优良的耐寒李氏木品种提供了重要证据。
