State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
China National Botanical Garden, Beijing, 100093, China.
Commun Biol. 2024 Jan 19;7(1):114. doi: 10.1038/s42003-024-05786-6.
The naturally occurring bisexual cone of gymnosperms has long been considered a possible intermediate stage in the origin of flowers, but the mechanisms governing bisexual cone formation remain largely elusive. Here, we employed transcriptomic and DNA methylomic analyses, together with hormone measurement, to investigate the molecular mechanisms underlying bisexual cone development in the conifer Picea crassifolia. Our study reveals a "bisexual" expression profile in bisexual cones, especially in expression patterns of B-class, C-class and LEAFY genes, supporting the out of male model. GGM7 could be essential for initiating bisexual cones. DNA methylation reconfiguration in bisexual cones affects the expression of key genes in cone development, including PcDAL12, PcDAL10, PcNEEDLY, and PcHDG5. Auxin likely plays an important role in the development of female structures of bisexual cones. This study unveils the potential mechanisms responsible for bisexual cone formation in conifers and may shed light on the evolution of bisexuality.
裸子植物中自然存在的两性球果长期以来一直被认为是花起源的可能中间阶段，但控制两性球果形成的机制在很大程度上仍难以捉摸。在这里，我们采用转录组学和 DNA 甲基化组学分析，以及激素测量，研究了松柏类植物云杉中两性球果发育的分子机制。我们的研究揭示了两性球果中“两性”的表达模式，特别是在 B 类、C 类和 LEAFY 基因的表达模式中，支持了雄性模型的出现。GGM7 可能对启动两性球果至关重要。两性球果中的 DNA 甲基化重排影响了包括 PcDAL12、PcDAL10、PcNEEDLY 和 PcHDG5 在内的关键基因在球果发育中的表达。生长素可能在两性球果雌性功能结构的发育中发挥重要作用。本研究揭示了裸子植物中两性球果形成的潜在机制，可能为两性性的进化提供线索。
