State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
Development. 2019 Aug 19;146(16):dev177410. doi: 10.1242/dev.177410.
Flowers of honey plants () face various abiotic stressors, including rain, that can damage pollens and dilute nectar. Many species are thought to have evolved a modified corolla base termed the corolla neck to prevent raindrops from contacting the nectar. Although this hypothesis was postulated long ago, direct validation is lacking. Here, we have evaluated , the corolla tube of which differentiates into distinct regions: a conical tube above that connects to an inflated base through a constriction. This constriction and inflated base are collectively referred to as the corolla neck. Using transcriptomic sequencing and genome-editing approaches, we have characterized an gene, , that is involved in formation of the corolla neck. was found expressed in the epidermis of the corolla neck. Cells in the corolla bottom differentiated and expanded in wild-type , whereas such cells in loss-of-function mutants failed to develop into a corolla neck. Water easily contacted the nectary in the absence of the corolla neck. Taken together, our study unveils a novel gene that controls corolla tube differentiation and demonstrates a hypothetical property of the corolla neck.
蜜源植物的花朵面临着各种非生物胁迫因素，包括雨水，这些因素可能会破坏花粉并稀释花蜜。许多物种被认为已经进化出一种改良的花冠基部，称为花冠颈，以防止雨滴接触到花蜜。尽管很久以前就提出了这一假说，但缺乏直接验证。在这里，我们评估了 ，其花冠管分化为不同的区域：一个连接到膨胀基部的圆锥形管，通过一个收缩连接。这个收缩和膨胀的基部统称为花冠颈。使用转录组测序和基因组编辑方法，我们已经描述了一个 基因 ，它参与花冠颈的形成。 在花冠颈的表皮中表达。在野生型中，花冠底部的细胞分化并扩张，而在功能丧失突变体中，这些细胞无法发育成花冠颈。在没有花冠颈的情况下，水很容易接触到蜜腺。综上所述，我们的研究揭示了一个控制花冠管分化的新基因，并证明了花冠颈的一个假设特性。
