Li Na, Zhang Yanfang, Huo Xiuwen, Xing Linan, Ge Mingran, Suo Ningning
College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010018, China.
Int J Mol Sci. 2025 Jun 16;26(12):5756. doi: 10.3390/ijms26125756.
Yam (,hereafter referred to as ) is a staple tropical tuber crop with notable nutritional and economic value. Its development and yield depend on efficient sucrose allocation from source tissues. Sucrose transporters (SUTs), a conserved family of membrane proteins, mediate sucrose loading, translocation, and unloading. Although well-studied in model plants and cereals, SUTs in yam remain largely uncharacterized. This study aims to identify and characterize the gene family in yam and explore their roles in sucrose transport and tuber development. We conducted a genome-wide analysis of yam genes, including gene structure, subcellular localization, and phylogeny. Molecular docking was used to predict sucrose-binding residues, and qRT-PCR assessed gene expression across tissues and tuber developmental stages. Eight genes were identified and classified based on sequence similarity and domain structure. Docking analysis revealed key residues involved in sucrose binding and possible conformational shifts influencing transport. Expression profiling showed that most genes, especially in the tuber apex, were progressively upregulated during development, suggesting roles in sucrose unloading and cell expansion. Additionally, functional validation of in Arabidopsis thaliana confirmed its involvement in sucrose transport, supporting its role in yam sucrose partitioning. Yam genes, especially those highly expressed in sink tissues, are involved in sucrose partitioning and tuber development. These findings provide structural and functional insights into SUT-mediated sugar transport and lay a foundation for improving sucrose utilization and yield in yam and other tuber crops.
山药（以下简称“薯蓣”）是一种重要的热带块茎作物，具有显著的营养和经济价值。其生长发育和产量取决于源组织中蔗糖的高效分配。蔗糖转运蛋白（SUTs）是一类保守的膜蛋白家族，介导蔗糖的装载、转运和卸载。尽管在模式植物和谷类作物中已得到充分研究，但薯蓣中的SUTs在很大程度上仍未被鉴定。本研究旨在鉴定和表征薯蓣中的SUT基因家族，并探讨它们在蔗糖运输和块茎发育中的作用。我们对薯蓣的SUT基因进行了全基因组分析，包括基因结构、亚细胞定位和系统发育。利用分子对接预测蔗糖结合残基，并通过qRT-PCR评估基因在不同组织和块茎发育阶段的表达。根据序列相似性和结构域结构鉴定并分类了8个SUT基因。对接分析揭示了参与蔗糖结合的关键残基以及可能影响运输的构象变化。表达谱分析表明，大多数SUT基因，尤其是在块茎顶端，在发育过程中逐渐上调，表明它们在蔗糖卸载和细胞扩张中发挥作用。此外，在拟南芥中对DcSUT1的功能验证证实了其参与蔗糖运输，支持了其在薯蓣蔗糖分配中的作用。薯蓣SUT基因，尤其是那些在库组织中高表达的基因，参与蔗糖分配和块茎发育。这些发现为SUT介导的糖运输提供了结构和功能方面的见解，并为提高薯蓣和其他块茎作物的蔗糖利用率及产量奠定了基础。
