Jiang Ning, Cui Jun, Shi Yunsheng, Yang Guanglei, Zhou Xiaoxu, Hou Xinxin, Meng Jun, Luan Yushi
1School of Life Science and Biotechnology, Dalian University of Technology, 116024 Dalian, China.
2School of Computer Science and Technology, Dalian University of Technology, 116024 Dalian, China.
Hortic Res. 2019 Feb 1;6:28. doi: 10.1038/s41438-018-0096-0. eCollection 2019.
Our previous studies indicated that tomato miR482b could negatively regulate the resistance of tomato to and the expression of miR482b was decreased after inoculation with . However, the mechanism by which the accumulation of miR482b is suppressed remains unclear. In this study, we wrote a program to identify 89 long noncoding RNA (lncRNA)-originated endogenous target mimics (eTMs) for 46 miRNAs from our RNA-Seq data. Three tomato lncRNAs, lncRNA23468, lncRNA01308 and lncRNA13262, contained conserved eTM sites for miR482b. When lncRNA23468 was overexpressed in tomato, miR482b expression was significantly decreased, and the expression of the target genes, , was significantly increased, resulting in enhanced resistance to . Silencing lncRNA23468 in tomato led to the increased accumulation of miR482b and decreased accumulation of NBS-LRRs, as well as reduced resistance to . In addition, the accumulation of both miR482b and NBS-LRRs was not significantly changed in tomato plants that overexpressed lncRNA23468 with a mutated eTM site. Based on the VIGS system, a target gene of miR482b, , was silenced. The disease symptoms of the VIGS- tomato plants were in accordance with those of tomato plants in which lncRNA23468 was silenced after inoculation with . More severe disease symptoms were found in the modified plants than in the control plants. Our results demonstrate that lncRNAs functioning as eTMs may modulate the effects of miRNAs in tomato and provide insight into how the lncRNA23468-miR482b-NBS-LRR module regulates tomato resistance to .
我们之前的研究表明，番茄miR482b可负向调控番茄对[病原体名称未给出]的抗性，接种[病原体名称未给出]后miR482b的表达降低。然而，miR482b积累受到抑制的机制仍不清楚。在本研究中，我们编写了一个程序，从我们的RNA测序数据中为46个miRNA鉴定出89个长链非编码RNA（lncRNA）来源的内源性靶标模拟物（eTM）。三个番茄lncRNA，lncRNA23468、lncRNA01308和lncRNA13262，含有miR482b的保守eTM位点。当lncRNA23468在番茄中过表达时，miR482b的表达显著降低，靶基因[靶基因名称未给出]的表达显著增加，从而增强了对[病原体名称未给出]的抗性。在番茄中沉默lncRNA23468导致miR482b积累增加和NBS-LRRs积累减少，以及对[病原体名称未给出]的抗性降低。此外，在过表达具有突变eTM位点的lncRNA23468的番茄植株中，miR482b和NBS-LRRs的积累均未显著变化。基于病毒诱导的基因沉默（VIGS）系统，miR482b的一个靶基因[靶基因名称未给出]被沉默。VIGS-[靶基因名称未给出]番茄植株的病害症状与接种[病原体名称未给出]后lncRNA23468被沉默的番茄植株的症状一致。在改良植株中发现的病害症状比对照植株更严重。我们的结果表明，作为eTM发挥作用的lncRNA可能调节番茄中miRNA的作用，并为lncRNA23468-miR482b-NBS-LRR模块如何调节番茄对[病原体名称未给出]的抗性提供了见解。
