Wang Rui, Zhang Hualei, Liu Zihan, Lu Yingao, Lan Shouxin, Zhang Bin, Li Shuai, Li Qian, Ma Jingyu, Xiang Xiaoli, Li Changsheng
The National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei 230036, China.
The National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei 230036, China.
J Hazard Mater. 2025 Aug 15;494:138437. doi: 10.1016/j.jhazmat.2025.138437. Epub 2025 Apr 28.
Selenium (Se) plays a dual role in plant growth, functioning as both an essential micronutrient and a potential toxin. Understanding the regulatory mechanisms of Se tolerance is crucial for enhancing crop resilience and biofortification. In this study, we integrated transcriptomics (RNA-seq), chromatin accessibility (ATAC-seq), and genome-wide association studies (GWAS) to elucidate the regulatory networks governing Se responses in maize seedlings. Low Se concentrations (≤ 0.05 mM) enhanced plant growth and biomass accumulation, whereas high Se concentrations (≥ 0.1 mM) induced toxicity and suppressed growth. Different treatment groups exhibited dose-dependent transcriptional reprogramming, with significant upregulation of genes involved in glutathione biosynthesis, Se metabolism, and jasmonic acid (JA) signaling. Concurrent chromatin accessibility remodeling in promoter regions orchestrated the transcriptional responses of these key genes. Characterization of the ZmGSTs gene family revealed subfamily-specific expression patterns and regulatory mechanisms under Se stress. Integration of high-confidence transcriptional regulatory networks with GWAS data led to the identification of a key metabolic gene (ZmGSR2) in the selenium metabolism pathway and three important transcription factors (ZmWRKY48, ZmbZIP123, and ZmKNOX6) that specifically activated distinct ZmGSTs genes. This study provides novel insights into the genetic and epigenetic mechanisms underlying selenium tolerance and identifies potential targets for improving crop selenium adaptability.
硒（Se）在植物生长中发挥着双重作用，既是一种必需的微量营养素，又是一种潜在的毒素。了解硒耐受性的调控机制对于增强作物的抗逆性和生物强化至关重要。在本研究中，我们整合了转录组学（RNA测序）、染色质可及性（ATAC测序）和全基因组关联研究（GWAS），以阐明玉米幼苗中控制硒反应的调控网络。低硒浓度（≤0.05 mM）促进植物生长和生物量积累，而高硒浓度（≥0.1 mM）则诱导毒性并抑制生长。不同处理组表现出剂量依赖性的转录重编程，参与谷胱甘肽生物合成、硒代谢和茉莉酸（JA）信号传导的基因显著上调。启动子区域同时发生的染色质可及性重塑协调了这些关键基因的转录反应。ZmGSTs基因家族的特征揭示了硒胁迫下亚家族特异性的表达模式和调控机制。将高可信度的转录调控网络与GWAS数据整合，导致在硒代谢途径中鉴定出一个关键代谢基因（ZmGSR2）和三个重要的转录因子（ZmWRKY48、ZmbZIP123和ZmKNOX6），它们特异性激活不同的ZmGSTs基因。本研究为硒耐受性的遗传和表观遗传机制提供了新的见解，并确定了提高作物硒适应性的潜在靶点。
