小RNA介导蜡质芽胞杆菌AR156激活MAPK通路诱导拟南芥系统抗病性研究  

Small RNA mediated Bacillus cereus AR156 induces systemic resistance in Arabidopsis through activation of MAPK pathway

作　　者：贺婵 汪顺娥 郝海婷 郭坚华[1] 赵弘巍[1] 牛冬冬[1] HE Chan;WANG Shun-e;HAO Hai-ting;GUO Jian-hua;ZHAO Hong-wei;NIU Dong-dong(College of Plant Protection,Nanjing Agricultural University,Nanjing 210095,China;College of Plant Science,Tarim University,Arar 843300,China)

机构地区：[1]南京农业大学植物保护学院,南京210095 [2]塔里木大学植物科学学院,塔里木843300

出　　处：《植物病理学报》2021年第5期796-806,共11页Acta Phytopathologica Sinica

基　　金：中央高校基本科研业务费专项资金资助(KYLH202007)。

摘　　要：蜡质芽胞杆菌AR156是一种根围促生细菌,可以诱导拟南芥产生对丁香假单胞番茄致病变种(Pseudomonas syringae pv.tomato DC3000,Pst DC3000)的系统抗性(Induced Systemic Resistance,ISR)。本研究发现,AR156预处理植物后接种病原菌Pst DC3000后的0 min~60 min内,能够迅速激活丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)MPK3和MPK6的表达。同时,AR156可诱导mpk3和mpk6单突变体对Pst DC3000的抗性,而在mpk3mpk6双突变体中则丧失诱导抗病的能力,表明MPK3和MPK6在AR156介导的诱导抗病中具有重要调控功能,且存在功能冗余。进一步研究发现,和对照相比,在接种72 h后,AR156可以诱导野生型拟南芥PR1蛋白的表达,但双突变体中并没有诱导作用。接种48 h后,过氧化氢的积累和胼胝质沉积也表现出相似结果。此外,通过对野生型和mpk3mpk6双突变体进行小RNA高通量测序发现,MAPK能够影响miRNA的表达,并通过qRT-PCR证实了部分小RNA的差异表达水平,表明MPK3/6可以调控植物miRNA的积累。研究表明MAPK在AR156激发ISR中发挥重要作用,并参与调控植物miRNA的表达水平。Bacillus cereus AR156 is a plant growth-promoting rhizobacterium(PGPR)that triggers induced systemic resistance(ISR)in Arabidopsis against Pseudomonas syringae pv.tomato DC3000(Pst DC3000)infection.In this study we found that Arabidopsis mitogen-activated protein kinase(MAPK)3 and 6(MPK3 and MPK6)were rapidly activated within 0 min-60 min after Pst DC3000 inoculation.Interestingly,MPK3 and MPK6 accumulation was more significant in AR156 pre-treated plants than control treatments.Moreover,AR156 pre-treatment was able to protect plants against Pst DC3000 only in mpk3 or mpk6 single mutants,but not in the mpk3 mpk6 double mutant.We therefore conclude that MPK3 and MPK6 may play redundant roles in the AR156-mediated ISR.AR156 could induce the expression of PR1 protein in wild-type Arabidopsis thaliana after 72 h of inoculation,but this induction was absent in the double mutants.Other defence response indicators such as hydrogen peroxide accumulation and callose deposition also showed similar results.In addition,comparative analysis on small RNA population between wild-type and mpk3 mpk6 double mutants showed that MAPK preferentially influenced the expression a group of miRNA.Our results demonstrate that MAPKs may play important roles in AR156-triggered ISR,in which manipulating small RNA accumulation may be accounted for.

关 键 词：蜡质芽胞杆菌AR156 MAPK 诱导系统抗病性 MIRNA 

分 类 号：S432.1[农业科学—植物病理学]