OsDCL1基因沉默突变体诱导稻瘟病抗性的转录组分析  

Transcriptome analysis of the OsDCL1-RNAi rice mutant enhancing resistance to rice blast

作　　者：张丹丹[1,2] 吴殿星[1] 周波[2] 

机构地区：[1]浙江大学原子核农业科学研究所,杭州310029 [2]浙江省农业科学院病毒与生物技术研究所,杭州310029

出　　处：《植物病理学报》2016年第2期223-234,共12页Acta Phytopathologica Sinica

基　　金：国家863计划资助项目(2012AA101103)

摘　　要：稻瘟病是严重危害水稻生长的真菌病害,每年给水稻生产带来重大经济损失。与野生型日本晴NPB相比,OsDCL1基因沉默突变体增强了水稻对稻瘟菌的广谱抗病性。为了解水稻OsDCL1-RNAi突变体的抗病机制,我们分析和比较了它和野生型日本晴NPB在稻瘟菌侵染前后转录组水平的变化。响应稻瘟菌侵染的7 129个差异表达基因(DEGs)中,NPB和OsDCL1-RNAi突变体分别有5 382和5 180个基因表达发生了变化,参与生物胁迫反应、信号通路、蛋白代谢和RNA调控4个通路的基因明显被富集。以野生型未受稻瘟菌侵染的基因表达为对照,在OsDCL1-RNAi突变体中共发现1 318个DEGs,且超过70%是上调的,其中很多基因参与了生物胁迫反应(26.9%)和信号通路(11%),上调表达基因中与生物胁迫反应相关的主要为PR基因和细胞壁相关基因。另外,还发现10个茉莉酸相关基因和11个水杨酸相关基因分别在OsDCL1-RNAi突变体中显著下调和上调表达。在OsDCL1-RNAi突变体中还发现WRKY和MYB等一些转录因子家族以及部分受体类激酶被诱导表达。用qRT-PCR方法验证部分差异表达的基因,其结果与DEGs基本一致。OsDCL1-RNAi突变体中转录组变化的分析,为深入了解该突变体抗瘟性增强的机制奠定了基础。Rice blast causes serious damage to rice growth and great economic losses in rice production yearly.Compared to the wild type plants,OsDCL1-RNAi knock-down mutant plants showed enhanced resistance to rice blast. To investigate the resistant mechanism of the mutant to rice blast,we analyzed and compared the transcriptome profiling in the wild type andOsDCL1-RNAi mutant plants upon challenge with the rice blast pathogen.Out of 7 129 differentially expressed genes（ DEGs） responsive to the infection of rice blast pathogen,5382 and 5 180 were identified in NPB and OsDCL1-RNAi mutant,respectively. The genes involved in 4 pathway groups including biotic stress response,signaling,protein metabolism,and RNA regulation were significantly identified in the DEGs. Moreover,we identified 1 318 DEGs in OsDCL1-RNAi mutant compared to the wild type plants without pathogen infection. Of those DEGs in OsDCL1-RNAi mutant plants,70% were up-regulated and most of them were involved in two pathway groups,i. e.,biotic stress response and signaling. Interestingly,the genes encoding various families of pathogenesis related（ PR） and cell wall related proteins were frequently identified in biotic stress response genes. We also identified 10 jasmonic acid and 11 salicylic acid related genes that were down-and up-regulated in OsDCL1-RNAi mutant plants,respectively. The genes encoding transcription factors,e. g.,WRKY and MYB families,and some receptor kinases were also abundantly identified in OsDCL1-RNAi mutant plants. Some differentially expressed genes were selected for qRT-PCR validation,the result is consistent with the DEGs. The altered transcriptome profiling of OsDCL1-RNAi mutant plants documented in this study could provide new insights into the enhanced resistance mediated by the silencing of OsDCL1 in rice.

关 键 词：水稻 稻瘟菌 转录组 抗病机制 生物胁迫 

分 类 号：S432.44[农业科学—植物病理学]