Lu Xiujun, Mei Mei, Liu Lin, Xu Xin, Ai Wanfeng
Department of Forestry, Shenyang Agricultural University, Shenyang, China.
Key Laboratory of Silviculture of Liaoning Province, Shenyang, China.
Mol Ecol Resour. 2025 Jan;25(1):e14030. doi: 10.1111/1755-0998.14030. Epub 2024 Oct 30.
Magnolia sieboldii K. Koch (M. sieboldii) stands as an elegant tree species within the Magnoliaceae family, esteemed for its exquisite beauty, cultural significance and economic advantages. The species faces challenges in seed germination under natural conditions, primarily attributed to morphological dormancy. Despite its significance, the molecular mechanisms governing M. sieboldii seed germination remain elusive, compounded by the absence of genomic resources specific to this species. In this study, we present the first chromosome-scale genome assembly of M. sieboldii, with a total genome size of 2.01 Gb, including 1096 scaffolds assigned to 19 chromosomes (N50 = 102.4 Mb). Phylogenetic analyses, incorporating 13 plant species, illuminate the evolutionary independence of Magnoliids from monocots and eudicots, positioning them as a sister clade. Through RNA-seq analysis, we identify pivotal genes and pathways contributing to seed dormancy and germination. In addition, our investigation delves into the the far-red-impaired response (FAR1) transcription factor gene family, revealing their enrichment throughout evolution and their involvement in the intricate process of seed germination. This comprehensive genome sequencing initiative offers invaluable insights into the biological attributes of M. sieboldii, with a specific emphasis on unravelling the complexities of seed dormancy and germination.
天女木兰（Magnolia sieboldii K. Koch）是木兰科中一种优雅的树种，因其精致的美丽、文化意义和经济优势而备受推崇。该物种在自然条件下种子萌发面临挑战，主要归因于形态休眠。尽管其具有重要意义，但由于缺乏该物种特有的基因组资源，天女木兰种子萌发的分子机制仍不清楚。在本研究中，我们展示了首个天女木兰染色体水平的基因组组装，其基因组总大小为2.01 Gb，包括分配到19条染色体上的1096个支架（N50 = 102.4 Mb）。系统发育分析纳入了13种植物，阐明了木兰类植物与单子叶植物和双子叶植物在进化上的独立性，将它们定位为一个姊妹分支。通过RNA测序分析，我们确定了影响种子休眠和萌发的关键基因和途径。此外，我们的研究深入探讨了远红光受损反应（FAR1）转录因子基因家族，揭示了它们在整个进化过程中的富集以及它们参与种子萌发的复杂过程。这项全面的基因组测序计划为天女木兰的生物学特性提供了宝贵的见解，特别强调揭示种子休眠和萌发的复杂性。
