The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extreme...The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extremely diverse in structure and biological activity.However,an understanding of CLP-plant structure–function interactions currently remains elusive.Here,we identify medpeptin,a novel CLP from Pseudomonas mediterranea that consists of 22 amino acids.Medpeptin is synthesized by a non-ribosomal peptide synthase(NRPS)gene cluster and regulated by a quorum-sensing system.Further research indicates that medpeptin does not exhibit antimicrobial activity;instead,it induces plant cell death immunity and confers resistance to bacterial infection.Comparative transcriptome analysis and virus-induced gene silencing(VIGS)reveal a set of immune signaling candidates involved in medpeptin perception.Silencing of a cell-wall leucine-rich repeat extensin protein(NbLRX3)or a receptor-like protein kinase(NbRLK25)—but not BAK1 or SGT1—compromises medpeptin-triggered cell death and resistance to pathogen infection in Nicotiana benthamiana.Our findings point to a noncanonical mechanism of CLP sensing and suggest perspectives for the development of plant disease resistance.展开更多
基金funded by the National Key R&D Program of China(2022YFD1901300)the National Natural Science Foundation of China(31901932)+2 种基金the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202308 and Y2022PT12)the Beijing Innovation Consortium of Agriculture Research System(BAIC04-2022)the Science and Technology Programs of the Zunyi Tobacco(2021XM03)。
文摘The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extremely diverse in structure and biological activity.However,an understanding of CLP-plant structure–function interactions currently remains elusive.Here,we identify medpeptin,a novel CLP from Pseudomonas mediterranea that consists of 22 amino acids.Medpeptin is synthesized by a non-ribosomal peptide synthase(NRPS)gene cluster and regulated by a quorum-sensing system.Further research indicates that medpeptin does not exhibit antimicrobial activity;instead,it induces plant cell death immunity and confers resistance to bacterial infection.Comparative transcriptome analysis and virus-induced gene silencing(VIGS)reveal a set of immune signaling candidates involved in medpeptin perception.Silencing of a cell-wall leucine-rich repeat extensin protein(NbLRX3)or a receptor-like protein kinase(NbRLK25)—but not BAK1 or SGT1—compromises medpeptin-triggered cell death and resistance to pathogen infection in Nicotiana benthamiana.Our findings point to a noncanonical mechanism of CLP sensing and suggest perspectives for the development of plant disease resistance.
