Takeda Seiji, Nishikawa Yuki, Tachibana Tsutomu, Higaki Takumi, Sakamoto Tomoaki, Kimura Seisuke
Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo-Hangi-Cho, Sakyo-ku, Kyoto 606-8522, Japan.
Biotechnology Research Department, Kyoto Prefectural Agriculture Forestry and Fisheries Technology Center, Kitainayaduma-Oji 74, Seika-Cho, Kyoto 619-0244, Japan.
Plants (Basel). 2025 Jan 28;14(3):393. doi: 10.3390/plants14030393.
Orchids have evolved flowers with unique morphologies through coevolution with pollinators, such as insects. Among the floral organs, the lip (labellum), one of the three petals, exhibits a distinctive shape and plays a crucial role in attracting pollinators and facilitating pollination in many orchids. The lip of the terrestrial orchid is shaped like a flying white bird and is believed to attract and provide a platform for nectar-feeding pollinators, such as hawk moths. To elucidate the mechanism of lip morphogenesis, we conducted time-lapse imaging of blooming flowers to observe the extension process of the lip and analyzed the cellular morphology during the generation of serrations. We found that the wing part of the lip folds inward in the bud and fully expands in two hours after blooming. The serrations of the lip were initially formed through cell division and later deepened through polar cell elongation. Transcriptome analysis of floral buds revealed the expression of genes involved in floral organ development, cell division, and meiosis. Additionally, genes involved in serration formation are also expressed in floral buds. This study provides insights into the mechanism underlying the formation of the unique lip morphology in .
兰花通过与传粉者（如昆虫）的协同进化，演化出了具有独特形态的花朵。在花器官中，唇瓣（花瓣之一）呈现出独特的形状，在许多兰花吸引传粉者和促进授粉过程中起着关键作用。地生兰花的唇瓣形状像一只飞翔的白色鸟儿，据信能吸引以花蜜为食的传粉者（如鹰蛾）并为其提供一个平台。为了阐明唇瓣形态发生的机制，我们对盛开的花朵进行了延时成像，以观察唇瓣的伸展过程，并分析了锯齿状结构形成过程中的细胞形态。我们发现，唇瓣的翼状部分在花蕾中向内折叠，并在开花后两小时内完全展开。唇瓣的锯齿最初通过细胞分裂形成，随后通过细胞极性伸长加深。花芽的转录组分析揭示了参与花器官发育、细胞分裂和减数分裂的基因的表达。此外，参与锯齿形成的基因也在花芽中表达。本研究为 中独特唇瓣形态形成的潜在机制提供了见解。
