Zhu Wenjiao, Liu Xinru, Chen Min, Tao Nianjiao, Tendu Alexander, Yang Qing
College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Plants (Basel). 2021 Oct 23;10(11):2274. doi: 10.3390/plants10112274.
Verticillium wilt is a major disease that severely affects eggplant production, and a new eggplant miRNA named miRm0002 identified through high-throughput sequencing was highly induced by Verticillium wilt infection. However, the miRm0002 function was still elusive. In this study, the sequence of the miRm0002 precursor was cloned and transgenic eggplants were constructed. In vivo inoculation test and in vitro fungistatic test showed that overexpressing miRm0002 lines were more resistant to and inhibiting miRm0002 lines were more sensitive, compared to the wild-type (WT) control. Some physiological indicators were selected and the results showed that SOD, POD, and CAT activities were significantly increased in Verticillium wilt-infected overexpressing miRm0002 lines, indicating that the expression of miRm0002 activates the antioxidant system. QRT-PCR assay showed that the transcript expression of miRm0002 candidate target , a gene encoding auxin response factor was negatively related to miRm0002 in WT as well as transgenic eggplants. However, RLM-RACE mapping and degradome sequencing showed miRm0002 could not cleave the sequence of . Taken together, these data suggest that miRm0002 plays a positive role in the defense response of eggplant against Verticillium wilt.
黄萎病是严重影响茄子生产的主要病害，通过高通量测序鉴定出的一种名为miRm0002的新茄子微小RNA（miRNA）在黄萎病菌感染后被高度诱导。然而，miRm0002的功能仍不清楚。在本研究中，克隆了miRm0002前体的序列并构建了转基因茄子。体内接种试验和体外抑菌试验表明，与野生型（WT）对照相比，过表达miRm0002的株系对黄萎病菌更具抗性，而抑制miRm0002的株系更敏感。选择了一些生理指标，结果表明，在感染黄萎病菌的过表达miRm0002株系中，超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性显著增加，表明miRm0002的表达激活了抗氧化系统。定量逆转录聚合酶链反应（QRT-PCR）分析表明，miRm0002候选靶标（一个编码生长素响应因子的基因）的转录表达在野生型以及转基因茄子中与miRm0002呈负相关。然而，RNA连接酶介导的5′端快速扩增（RLM-RACE）定位和降解组测序表明，miRm0002不能切割该靶标的序列。综上所述，这些数据表明miRm0002在茄子对黄萎病的防御反应中发挥了积极作用。
