油菜miR6030通过靶标两个编码CC-NBS-LRR蛋白的基因调控对核盘菌的抗性

Brassica napus miR6030 negatively regulates resistance to Sclerotinia sclerotiorum via targeting two genes encoding CC-NBS-LRR proteins

miRNAs对油菜抗核盘菌(Sclerotinia sclerotiorum)的调控作用尚不明确。本研究分析了油菜miR6030在菌核病抗性调控中的功能和机制。结果表明,miR6030在油菜不同组织中表达水平有差异,以根和茎中较高,花中最低。miR6030瞬时超表达和沉默分析以及基因沉默转基因油菜植株分析结果均显示,miR6030负调控油菜对核盘菌的抗性。降解组分析和GUS染色分析显示,miR6030靶标2个产物具有CC-NBS-LRR(CNL)结构的基因BnaCnng64090D和BnaA09g10520D。这2个基因均正调控油菜对核盘菌的抗性。综上,油菜miR6030降解编码CNL蛋白的BnaCnng64090D和BnaA09g10520D基因转录本,从而负调控对菌核病的抗性。该研究结果增进了对miR6030生物学功能以及油菜对核盘菌抗性分子机制的理解,并为油菜抗菌核病分子育种提供新思路。

The role of miRNAs in regulating resistance to Sclerotinia sclerotiorum in oilseed rape(Brassica napus)is largely unknown.In this study,functions and mechanisms of miR6030 in resistance to S.sclerotiorum were analyzed.The results showed that miR6030 was expressed differentially in various tissues,higher in roots and stems while lowest in flowers.Silencing and transient over-expression of miR6030 in oilseed rape plants demonstrated that miR6030 negatively regulates resistance to S.sclerotiorum.The degradome analysis and GUS staining assay revealed that miR6030 targets BnaCnng64090D and BnaA09g10520D,which encode CC-NBS-LRR(CNL)proteins and positively regulate resistance to S.sclerotiorum.All the results indicated that miR6030 negatively regulates resistance to S.sclerotiorum via cleaving transcripts of the two CNL protein-encoding genes BnaCnng64090D and BnaA09g10520D.This study provides some insights into functions of miR6030 and molecular mechanisms underlying the resistance to S.sclerotiorum and new strategy for molecular breeding for the resistance of Brassica napus to S.sclerotiorum.