Wang Jinnan, Xu Dong, Sang Ya Lin, Sun Maotong, Liu Cuishuang, Niu Muge, Li Ying, Liu Laishuo, Han Xiaojiao, Li Jihong
Shandong Mountain Tai Forest Ecosystem National Station, Key Laboratory of Forest Cultivation in the Lower Yellow River, National Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai'an 271018, China.
Rubber Research Institute, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 570100, China.
Hortic Res. 2024 Sep 3;11(12):uhae249. doi: 10.1093/hr/uhae249. eCollection 2024 Dec.
, an arbor tree of the Oleaceae family, is an ecologically and economically valuable ornamental plant for its remarkable adaptability in landscaping. During breeding, we observed diverse floral shapes; however, no available genome for has hindered the widespread identification of genes related to flower morphology. Thus, a telomere-to-telomere (T2T) gap-free genome was generated. The assembly, incorporating high-coverage and long-read sequencing data, successfully yielded two complete haplotypes (687 and 683 Mb). The genome encompasses 42 864 predicted protein-coding genes, with all 46 telomeres and 23 centromeres in one haplotype. Whole-genome duplication analysis revealed that underwent one fewer event of whole-genome duplication after differentiation compared to other species in the Oleaceae family. Furthermore, flower vein diversity was the main reason for the differences in floral shapes. Auxin-related genes were responsible for petal shape formation on genome-based transcriptome analysis. Specifically, the removal and retention of the first intron in resulted in the production of two transcripts, and the differences in the expression levels of resulted in the variations of flower veins. Compared to transcripts lacking the first intron, transcripts with intron retention caused more severe decreases in the number and length of flower veins in transgenic . Our findings will deepen our understanding of flower morphology development and provide important theoretical support for the cultivation of Oleaceae.
[植物名称]，木犀科乔木，因其在园林景观中具有卓越的适应性，是一种具有生态和经济价值的观赏植物。在育种过程中，我们观察到了多样的花形；然而，[植物名称]缺乏可用的基因组阻碍了与花形态相关基因的广泛鉴定。因此，我们生成了一个端粒到端粒（T2T）无间隙基因组。该组装整合了高覆盖度和长读长测序数据，成功产生了两个完整的单倍型（687和683 Mb）。该基因组包含42864个预测的蛋白质编码基因，其中一个单倍型中包含所有46个端粒和23个着丝粒。全基因组重复分析表明，与木犀科其他物种相比，[植物名称]在分化后经历的全基因组重复事件少一次。此外，花脉多样性是花形差异的主要原因。基于基因组的转录组分析表明，生长素相关基因负责花瓣形状的形成。具体而言，[基因名称]中第一个内含子的去除和保留导致产生两种转录本，[基因名称]表达水平的差异导致花脉的变化。与缺乏第一个内含子的转录本相比，具有内含子保留的转录本在转基因[植物名称]中导致花脉数量和长度更严重的减少。我们的研究结果将加深我们对花形态发育的理解，并为木犀科植物的培育提供重要的理论支持。
