Overexpression of a miR393-Resistant Form of Transport Inhibitor Response Protein 1 (mTIR1) Enhances Salt Tolerance by Increased Osmoregulation and Na+ Exclusion in Arabidopsis thaliana
Overexpression of a miR393-Resistant Form of Transport Inhibitor Response Protein 1 (mTIR1) Enhances Salt Tolerance by Increased Osmoregulation and Na+ Exclusion in Arabidopsis thaliana
复制标题
DOI：
10.1093/pcp/pcu149
复制
发表时间：
2015-01-01
影响因子：
4.9
通讯作者：
Wang, Lilin
中科院分区：
文献类型：
--
作者：
Chen, Zhehao;Hu, Lingzhi;Wang, Lilin
土壤盐分是一种常见的环境胁迫因子，限制了全球农业生产。植物已经进化出不同的策略来实现耐盐性。miR 393已被鉴定为与生物和非生物胁迫密切相关，并且靶向编码生长素受体的F-box基因。miR 393-TIR 1/AFB 2/AFB 3调控模块被发现具有操纵生长素反应的多种功能。这项研究主要集中在miR 393及其靶点之一TIR 1上，发现它们在响应盐胁迫中发挥了潜在的作用。我们的研究结果表明，miR 393抗性TIR 1基因（mTIR 1）在拟南芥中的过表达明显增强了盐胁迫的耐受性，从而导致更高的发芽率，更少的水分损失，减少根伸长的抑制，延缓衰老，降低死亡率和稳定叶绿素含量。这些植株积累了更多的脯氨酸和花青素，表现出更强的渗透胁迫耐受性。一些盐胁迫相关基因的表达发生了改变，盐胁迫下这些植物体内钠含量可以降低。我们认为mTIR 1过表达引起的生长素信号的高度增加可能触发生长素介导的下游途径，从而通过抑制调节和增加Na+排斥来增强植物的盐胁迫抗性。
Soil salinity is a common environmental stress factor that limits agricultural production worldwide. Plants have evolved different strategies to achieve salt tolerance. miR393 has been identified as closely related to biotic and abiotic stresses, and targets F-box genes that encode auxin receptors. The miR393-TIR1/AFB2/AFB3 regulatory module was discovered to have multiple functions that manipulate the auxin response. This study focused on miR393 and one of its targets, TIR1, and found that they played potential roles in response to salt stress. Our results showed that overexpression of a miR393-resistant TIR1 gene (mTIR1) in Arabidopsis clearly enhanced salt stress tolerance, which led to a higher germination rate, less water loss, reduced inhibition of root elongation, delayed senescence, decreased death rate and stabilized Chl content. These plants accumulated more proline and anthocyanin, and displayed enhanced osmotic stress tolerance. The expression of some salt stress-related genes was altered, and sodium content can be reduced in these plants under salt stress. We proposed that highly increased auxin signaling by overexpression of mTIR1 may trigger auxin-mediated downstream pathways to enhance plant salt stress resistance by osmoregulation and increased Na+ exclusion.