College of Agronomy, State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, 3 Taicheng Road, Yangling, Xianyang 712100, China.
Int J Mol Sci. 2022 May 25;23(11):5917. doi: 10.3390/ijms23115917.
Drought has gradually become one of the most severe abiotic stresses on plants. Plants that experience stress training can exhibit enhanced stress tolerance. According to MicroRNA (miRNA) sequencing data, this study identified 195 candidate drought memory-related miRNAs in wheat, and targets of 64 (32.8%) candidate miRNAs were validated by degradome sequencing. Several drought memory-related miRNAs such as , , , , , , , , , and were validated as having a strong response to drought memory by regulating the expression of their target genes. In addition, overexpression of drought memory-related miRNA, , can remarkably improve the drought tolerance of transgenic . Drought memory can regulate plant cellular signal transduction, plant biosynthetic processes, and other biological processes to cope with drought via transcriptional memory. In addition, drought memory-related miRNAs can promote starch and sucrose catabolism and soluble sugar accumulation and regulate proline homeostasis to improve plant drought resistance. Our results could contribute to an understanding of drought memory in wheat seedlings and may provide a new strategy for drought-resistant breeding.
干旱逐渐成为植物面临的最严重的非生物胁迫之一。经历胁迫训练的植物可以表现出增强的胁迫耐受性。根据 MicroRNA（miRNA）测序数据，本研究在小麦中鉴定了 195 个候选干旱记忆相关 miRNA，通过降解组测序验证了 64 个（32.8%）候选 miRNA 的靶标。几个干旱记忆相关的 miRNA，如 miR156、miR164、miR167、miR169、miR390、miR393、miR395、miR396 和 miR398，通过调节其靶基因的表达，被验证对干旱记忆有强烈的响应。此外，过表达干旱记忆相关 miRNA miR167 和 miR398 可以显著提高转基因 的耐旱性。干旱记忆可以通过转录记忆调节植物细胞信号转导、植物生物合成过程和其他生物过程来应对干旱。此外，干旱记忆相关 miRNA 可以促进淀粉和蔗糖的分解以及可溶性糖的积累，并调节脯氨酸稳态以提高植物的抗旱性。我们的研究结果有助于理解小麦幼苗中的干旱记忆，并可能为抗旱性育种提供新的策略。
