Li Liumin, Wang Xueying, Li Hua, Ali Muhammad Moaaz, Hu Xiaobo, Oelmuller Ralf, Yousef Ahmed Fathy, Alrefaei Abdulwahed Fahad, Liu Jianfu, Chen Faxing
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
Institute of Horticultural Science and Engineering, Huaqiao University, Xiamen, 361021, Fujian, China.
BMC Plant Biol. 2025 Apr 2;25(1):416. doi: 10.1186/s12870-025-06443-8.
Orchid mycorrhizal (OM) fungi form mutualistic relationships with orchids, facilitating the uptake of minerals from the soil in exchange for sugars and lipids provided by the plant. In this study, we explored the role of the DoSWEET14 sugar transporter in Dendrobium officinale during OM symbiosis. Transcriptome sequencing revealed significant changes in gene expression in mycorrhizal roots, particularly the upregulation of DoSWEET14. Subcellular localization studies confirmed that DoSWEET14 is localized to the plasma membrane, suggesting its involvement in nutrient exchange between the orchid and OM fungi. Complementation assays using a yeast strain deficient in hexose transport demonstrated that DoSWEET14 has broad substrate specificity, efficiently transporting multiple monosaccharides. Additionally, overexpression of DoSWEET14 in Arabidopsis increased sugar content without affecting biomass, supporting its role in carbohydrate transport and storage during symbiosis. These findings suggest that DoSWEET14 plays a key role in regulating carbon allocation and stabilizing the mutualistic relationship between Dendrobium officinale and OM fungi.
兰花菌根（OM）真菌与兰花形成共生关系，促进从土壤中吸收矿物质，以换取植物提供的糖类和脂质。在本研究中，我们探究了铁皮石斛中DoSWEET14糖转运蛋白在OM共生过程中的作用。转录组测序揭示了菌根化根系中基因表达的显著变化，特别是DoSWEET14的上调。亚细胞定位研究证实DoSWEET14定位于质膜，表明其参与兰花与OM真菌之间的养分交换。使用缺乏己糖转运的酵母菌株进行的互补试验表明，DoSWEET14具有广泛的底物特异性，能有效转运多种单糖。此外，DoSWEET14在拟南芥中的过表达增加了糖含量，而不影响生物量，支持其在共生过程中碳水化合物运输和储存中的作用。这些发现表明，DoSWEET14在调节碳分配和稳定铁皮石斛与OM真菌之间的共生关系中起关键作用。
