Monreal Contreras Hugo Alberto, Arthikala Manoj-Kumar, Lara Miguel, Nanjareddy Kalpana
Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores Unidad León-Universidad Nacional Autónoma de México (UNAM), Guanajuato, México.
Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, México.
Plant Signal Behav. 2025 Dec;20(1):2507736. doi: 10.1080/15592324.2025.2507736. Epub 2025 May 19.
Root hairs are essential for nutrient acquisition and rhizosphere interactions in vascular plants. While the Target of Rapamycin (TOR) kinase is a well established regulator of growth and metabolism, its role in root hair development in remains underexplored. In this study, we investigated the role of TOR in root hair morphogenesis using RNA interference (RNAi)-mediated downregulation of and transcriptomic profiling. Microscopic examination of -RNAi roots confirmed significant reductions in root hair length and density. Transcriptomic analysis revealed differential expression of 148 homologs of root hair-related genes, with 63 genes downregulated and 85 upregulated. Gene Ontology enrichment analysis indicated that these differentially expressed genes (DEGs) were primarily involved in cellular development, cell differentiation, and redox regulation. Upregulation of phosphoinositide metabolism genes, ROS generators, and cell wall-related extensins suggests compensatory tip growth responses under TOR suppression. On the otherhand, repression of key auxin signaling genes and cell wall-loosening proteins such as and indicates a shift away from elongation processes. Protein - protein interaction network analysis highlighted phosphoinositide and ROP GTPase signaling hubs as major pathways affected by TOR inhibition, suggesting that TOR indirectly modulates cell polarity and membrane dynamics essential for root hair development. These findings provide further evidence of TOR as a central integrator of hormonal, metabolic, and structural cues during root hair formation.
根毛对于维管植物获取养分和根际相互作用至关重要。虽然雷帕霉素靶蛋白（TOR）激酶是生长和代谢的一个成熟调节因子，但其在根毛发育中的作用仍未得到充分研究。在本研究中，我们使用RNA干扰（RNAi）介导的基因下调和转录组分析来研究TOR在根毛形态发生中的作用。对RNAi根的显微镜检查证实根毛长度和密度显著降低。转录组分析揭示了148个根毛相关基因同源物的差异表达，其中63个基因下调，85个基因上调。基因本体富集分析表明，这些差异表达基因（DEGs）主要参与细胞发育、细胞分化和氧化还原调节。磷酸肌醇代谢基因、活性氧产生剂和细胞壁相关伸展蛋白的上调表明在TOR抑制下存在补偿性顶端生长反应。另一方面，关键生长素信号基因和细胞壁松弛蛋白（如和）的抑制表明远离伸长过程的转变。蛋白质-蛋白质相互作用网络分析突出了磷酸肌醇和ROP GTPase信号枢纽是受TOR抑制影响的主要途径，表明TOR间接调节根毛发育所必需的细胞极性和膜动力学。这些发现进一步证明了TOR是根毛形成过程中激素、代谢和结构信号的中央整合者。
