Xue Yonglu, Yu Qiwei, Chen Gang, Luo Zhenbao, Pi Kai, Xie Baolin, Wu Kaiping, Shi Chenhao, Liu Renxiang
Guizhou Provincial Key Laboratory for Tobacco Quality Improvement and Efficiency Enhancement, Guiyang, 550025, People's Republic of China.
College of Tobacco, Guizhou University, Guiyang, 550025, People's Republic of China.
Plant Cell Rep. 2025 Aug 29;44(9):203. doi: 10.1007/s00299-025-03587-7.
WGCNA mined the unknown gene NtLYK5, and VIGS and RNA-seq analyses suggested that NtLYK5 mediates the negative regulation of hydrogen peroxide production for drought resistance. Drought during the seedling stage of tobacco (Nicotiana tabacum), a water-sensitive and economically important crop, has serious adverse effects on transplant survival and tobacco plant growth. In this study, we conducted transcriptome sequencing on drought-tolerant and drought-sensitive recombinant inbred lines (RILs) from the F7 generation of the cross "NC82 × Bina No. 1." Using weighted gene co-expression network analysis (WGCNA), BLAST alignment, bioinformatics analysis, and qRT-PCR, we identified a key candidate gene NtLYK5, which is highly associated with drought resistance but previously had an unknown function. Virus-induced gene silencing to suppress NtLYK5 expression in tobacco enhanced drought resistance, reduced hydrogen peroxide (HO) levels, and increased catalase (CAT) activity. Further transcriptomic analysis of drought-tolerant and drought-sensitive lines revealed differentially expressed genes (DEGs) associated with NtLYK5-induced drought resistance, which were significantly enriched in the MAPK signaling pathway. Under drought stress, HO acts as a signaling molecule affecting the expression of DEGs such as ANP1, which induces HO production and cell death, thereby preventing the stomata from closing properly. These results suggest that NtLYK5 is a key gene that negatively regulates drought tolerance in tobacco seedlings by modulating HO-induced stomatal movement.
加权基因共表达网络分析（WGCNA）挖掘出未知基因NtLYK5，病毒诱导基因沉默（VIGS）和RNA测序分析表明，NtLYK5介导过氧化氢产生的负调控以实现抗旱性。烟草（Nicotiana tabacum）是一种对水分敏感且具有重要经济价值的作物，其幼苗期干旱对移栽成活率和烟株生长有严重不利影响。在本研究中，我们对“NC82×Bina No.1”杂交组合F7代的耐旱和干旱敏感重组自交系（RIL）进行了转录组测序。通过加权基因共表达网络分析（WGCNA）、BLAST比对、生物信息学分析和qRT-PCR，我们鉴定出一个关键候选基因NtLYK5，它与抗旱性高度相关，但之前功能未知。在烟草中通过病毒诱导基因沉默抑制NtLYK5表达可增强抗旱性、降低过氧化氢（H₂O₂）水平并提高过氧化氢酶（CAT）活性。对耐旱和干旱敏感品系的进一步转录组分析揭示了与NtLYK5诱导的抗旱性相关的差异表达基因（DEG），这些基因在丝裂原活化蛋白激酶（MAPK）信号通路中显著富集。在干旱胁迫下，H₂O₂作为一种信号分子影响如ANP1等差异表达基因的表达，ANP1诱导H₂O₂产生和细胞死亡，从而阻止气孔正常关闭。这些结果表明，NtLYK5是一个关键基因，通过调节H₂O₂诱导的气孔运动对烟草幼苗的耐旱性进行负调控。
