Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China.
College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Int J Mol Sci. 2019 Aug 16;20(16):4001. doi: 10.3390/ijms20164001.
Sugar transporters of the family mediate cross membrane movement of mono- and disaccharides and play vital roles in diverse physiological and pathophysiological processes, including sink-source relationship, pathogen responses, reproductive growth, and development. However, it remains to be determined how these transporters function in non-module plants of agricultural significance, given the evolutionarily diverse traits. In this study, we combined transcriptome analysis, rapid amplification of cDNA ends-cloning (RACE-cloning), expression profiling, and heterologous functional assay to identify genes that may have potential roles during flower opening and sexual reproduction in . During the anthesis, the floral organs of express seven homologous genes from all four clades of the family. and are significantly upregulated when flowers are fully opened, up to 6- and 3-fold compared to unopened buds, respectively. The other transporters, , , , and are also accumulated slightly at stage associated with fragrance release, whereas only the vacuole transporter showed small decrease in transcript level after anthesis. The , a clade II member, is capable to complement yeast cell uptake on most tested sugar substrates with a preference for hexoses, while the clade I transporter mediates merely galactose import when expressed in yeast. Our results provide first evidence for further investigation on sugar transport and allocation during flowering and reproductive processes in .
家族的糖转运蛋白介导单糖和二糖的跨膜运动，在包括源库关系、病原体反应、生殖生长和发育在内的多种生理和病理生理过程中发挥着重要作用。然而，鉴于其进化上的多样性特征，这些转运蛋白在具有农业意义的非模块植物中如何发挥作用仍有待确定。在这项研究中，我们结合转录组分析、快速扩增 cDNA 末端克隆（RACE-cloning）、表达谱分析和异源功能测定，鉴定了 中可能在开花和有性生殖过程中发挥作用的基因。在开花期间， 的花器官表达来自家族的四个分支的七个同源基因。当花朵完全开放时， 和 显著上调，与未开放的花蕾相比分别上调了 6 倍和 3 倍。其他转运蛋白 、 、 、 和 在与香味释放相关的阶段也略有积累，而只有液泡转运蛋白 在开花后转录水平略有下降。 ，一个分支 II 成员，能够在酵母细胞摄取大多数测试糖底物上补充，对己糖有偏好，而分支 I 转运蛋白 仅在酵母中表达时介导半乳糖的导入。我们的研究结果为进一步研究 在开花和生殖过程中的糖转运和分配提供了初步证据。
