Department of Crop Genetics and Breeding, College of Agronomy, Hebei Agricultural University, Baoding 071001, China.
North China Key Laboratory for Crop Germplasm Resources of the Education Ministry, Hebei Agricultural University, Baoding 071001, China.
Int J Mol Sci. 2019 Mar 13;20(6):1268. doi: 10.3390/ijms20061268.
To unravel the molecular mechanisms underpinning maize ( L.) drought stress tolerance, we conducted comprehensive comparative transcriptome and physiological analyses of drought-tolerant YE8112 and drought-sensitive MO17 inbred line seedlings that had been exposed to drought treatment for seven days. Resultantly, YE8112 seedlings maintained comparatively higher leaf relative water and proline contents, greatly increased peroxidase activity, but decreased malondialdehyde content, than MO17 seedlings. Using an RNA sequencing (RNA-seq)-based approach, we identified a total of 10,612 differentially expressed genes (DEGs). From these, we mined out four critical sets of drought responsive DEGs, including 80 specific to YE8112, 5140 shared between the two lines after drought treatment (SD_TD), five DEGs of YE8112 also regulated in SD_TD, and four overlapping DEGs between the two lines. Drought-stressed YE8112 DEGs were primarily associated with nitrogen metabolism and amino-acid biosynthesis pathways, whereas MO17 DEGs were enriched in the ribosome pathway. Additionally, our physiological analyses results were consistent with the predicted RNA-seq-based findings. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis and the RNA-seq results of twenty representative DEGs were highly correlated (² = 98.86%). Crucially, tolerant line YE8112 drought-responsive genes were predominantly implicated in stress signal transduction; cellular redox homeostasis maintenance; , , , and transcriptional factor modulated; carbohydrate synthesis and cell-wall remodeling; amino acid biosynthesis; and protein ubiquitination processes. Our findings offer insights into the molecular networks mediating maize drought stress tolerance.
为了揭示玉米(L.)耐旱性的分子机制,我们对经过七天干旱处理的耐旱 YE8112 和敏感 MO17 自交系幼苗进行了全面的比较转录组和生理分析。结果表明,YE8112 幼苗保持相对较高的叶片相对水和脯氨酸含量,过氧化物酶活性显著增加,而丙二醛含量降低。采用 RNA 测序(RNA-seq)方法,我们共鉴定了 10612 个差异表达基因(DEGs)。从中我们挖掘出四组关键的干旱响应 DEGs,包括 80 个 YE8112 特异的,5140 个在干旱处理后两个系共享的(SD_TD),YE8112 中也在 SD_TD 中调节的 5 个 DEGs,以及两个系之间重叠的 4 个 DEGs。受干旱胁迫的 YE8112 的 DEGs 主要与氮代谢和氨基酸生物合成途径相关,而 MO17 的 DEGs 富集在核糖体途径中。此外,我们的生理分析结果与预测的 RNA-seq 结果一致。此外,二十个代表性 DEGs 的定量实时聚合酶链反应(qRT-PCR)分析和 RNA-seq 结果高度相关(²=98.86%)。重要的是,耐旱系 YE8112 干旱响应基因主要参与胁迫信号转导;细胞氧化还原稳态维持;转录因子调节;碳水化合物合成和细胞壁重塑;氨基酸生物合成;和蛋白质泛素化过程。我们的研究结果为玉米耐旱性的分子网络提供了新的见解。