Comparative transcriptome reveals genes regulating root hair length of barley(基于比较转录组发掘控制大麦根毛长度的基因)

Root hairs, the primary sites for water and nutrient uptake, make barley—with its long root hair traits and strong environmental adaptability—an ideal candidate for investigating root hair regulatory genes. In this study, by analyzing the transcriptome of barley roots which exhibiting significant differences in root hair length, we identified 274 shared differentially expressed genes. Further analyses via Gene Ontology (GO) functional annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, MapMan metabolic pathway analysis, and protein-protein interaction (PPI) network prediction led to the identification of a set of genes regulating root hair length, with higher expression levels in long root hair genotypes than in short ones. These genes primarily encompass genes involved in hormone signaling pathways, including the auxin, ethylene, and salicylic acid pathways, as well as secondary metabolism pathways, such as the phenylpropanoid, lignin, and lignan pathways. They also include genes related to peroxidase and glutathione S-transferase that maintaining reactive oxygen species (ROS) homeostasis, ubiquitin pathway, receptor kinases, and calcium signal transduction. The results from this study shed initial light on the molecular mechanisms controlling barley root hair length and also provide candidate genes for the genetic improvement of crop root traits. . 根毛是吸收水分和养分的主要部位，大麦因长根毛特征和强环境适应性成为发掘根毛调控基因的理想材料。本研究通过分析根毛长度差异显著的大麦根系转录组，鉴定到274个共有差异表达基因；进一步通过基因本体（Gene Ontology, GO）功能注释、京都基因和基因组数据库（Kyoto Encyclopedia of Genes and Genomes, KEGG）富集、MapMan代谢通路分析和蛋白质-蛋白质相互作用（protein-protein interaction, PPI）网络预测，挖掘到一批根毛长度调控基因，它们在长根毛基因型中有较高的表达水平。这些基因主要包括生长素、乙烯和水杨酸等激素信号通路基因，苯丙素、木质素和木脂素等次生代谢通路基因，维持活性氧稳态的过氧化物酶和谷胱甘肽巯基转移酶基因，泛素通路基因，受体激酶类以及钙信号转导基因。本研究结果初步揭示了大麦根毛长度的分子调控机制，为作物根系性状遗传改良提供了候选基因。