Department of Agronomy and Plant Breeding, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
Department of Horticulture, Agricultural Faculty, Ataturk University, Erzurum, Turkey.
PLoS One. 2020 Feb 18;15(2):e0228850. doi: 10.1371/journal.pone.0228850. eCollection 2020.
Environmental stresses influence the growth and development of plants by influencing patterns of gene expression. Different regulators control gene expression, including transcription factors (TFs) and microRNAs. MicroRNAs (miRNAs: ~21 nucleotides long) are encoded by miRNA genes transcribed by RNA polymerase II (RNP-II) and play key roles in plant development and physiology. There is little knowledge currently available on miRNAs and their function in response to environmental stresses in safflower. To obtain more information on safflower miRNAs, we initially used a comparative genomics approach and succeeded in identifying 126 miRNAs belonging to 29 conserved families, along with their target genes. In this study, we investigated the expression profiles of seven conserved miRNAs related to drought, salinity, heat, and Cd stress in the leaf and root organs using qRT-PCR, for the first time. Gene Ontology (GO) analysis found that target genes of miRNAs are often TFs such as AP2/ERF and HD-ZIP as well as NAC domain-containing proteins. Expression analyses confirmed that miRNAs can play a vital role in keeping safflower stress-tolerant. Differential expression of miR156, miR162, miR164, miR166, miR172, miR398, and miR408 regulate the expression of their respective target genes. These genes activate several pathways leading to physiological and biochemical responses to abiotic stresses. Some conserved miRNAs were regulated by abiotic stresses. Our finding provides valuable information to understand miRNAs in relation to different abiotic stresses in safflower.
环境胁迫通过影响基因表达模式来影响植物的生长和发育。不同的调节剂控制基因表达，包括转录因子（TFs）和 microRNAs。microRNAs（miRNAs：~21 个核苷酸长）由 RNA 聚合酶 II（RNP-II）转录的 miRNA 基因编码，在植物发育和生理中发挥关键作用。目前，关于 miRNA 及其在红花对环境胁迫的反应中的功能知之甚少。为了获得更多关于红花 miRNA 的信息，我们最初使用比较基因组学方法成功鉴定了 126 个属于 29 个保守家族的 miRNA，以及它们的靶基因。在这项研究中，我们首次通过 qRT-PCR 研究了与干旱、盐胁迫、热胁迫和 Cd 胁迫相关的七个保守 miRNA 在叶片和根器官中的表达谱。基因本体论（GO）分析发现，miRNA 的靶基因通常是 TF，如 AP2/ERF 和 HD-ZIP 以及 NAC 结构域蛋白。表达分析证实，miRNA 可以在保持红花耐胁迫方面发挥重要作用。miR156、miR162、miR164、miR166、miR172、miR398 和 miR408 的差异表达调节其各自靶基因的表达。这些基因激活了几个导致对非生物胁迫产生生理和生化反应的途径。一些保守的 miRNA 受到非生物胁迫的调节。我们的发现为理解红花中不同非生物胁迫下的 miRNA 提供了有价值的信息。
