摘要
Plants perceive pathogen-associated molecular patterns(PAMPs)using plasma-membrane-localized pattern recognition receptors(PRRs)to activate broad-spectrum pattern-triggered immunity.However,the regulatory mechanisms that ensure robust broad-spectrum plant immunity remain largely unknown.Here,we reveal that the transcription factor WRKY8 has a dual role in the transcriptional regulation of PRR genes:repressing expression of the nlp20/nlp24 receptor gene RLP23 while promoting that of the chitin receptor gene CERK1.SsNLP1 and SsNLP2,two nlp24-type PAMPs from the destructive fungal pathogen Sclerotinia sclerotiorum,activate two calcium-elicited kinases,CPK4 and CPK11,which phosphorylate WRKY8 and thus release its inhibition on RLP23 to promote accumulation of RLP23 transcripts.Meanwhile,SsNLPs activate the RLCK-type kinase PBL19,which phosphorylates WRKY8 and thus enhances accumulation of CERK1 transcripts.Intriguingly,RLP23 is repressed at later stage by PBL19-mediated phosphorylation of WRKY8,thus avoiding excessive immunity and enabling normal growth.Our findings unveil a plant strategy of“killing two birds with one stone”to elicit robust broad-spectrum immunity.This strategy is based on PAMP-triggered fine-tuning of a dual-role transcription factor to simultaneously amplify two PRRs that recognize PAMPs conserved across a wide range of pathogens.Moreover,our results reveal a novel plant strategy for balancing the trade-off between growth and immunity by fine-tuning the expression of multiple PRR genes.
基金
National Natural Science Foundation of China(no.31871947)
Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding(no.2021C02064)
Hainan Provincial Natural Science Foundation of China(no.324CXTD430)
Zhejiang Provincial Natural Science Foundation of China(no.LZ18C140002).
