Elicitor

About: Elicitor is a research topic. Over the lifetime, 3589 publications have been published within this topic receiving 167676 citations.

Plants have a sensitive perception system for the most conserved domain of bacterial flagellin

Abstract: The flagellum is an important virulence factor for bacteria pathogenic to animals and plants. Here we demonstrate that plants have a highly sensitive chemoperception system for eubacterial flagellins, specifically targeted to the most highly conserved domain within its N terminus. Synthetic peptides comprising 15-22 amino acids of this domain acted as elicitors of defence responses at sub-nanomolar concentrations in cells of tomato and several other plant species. Peptides comprising only the central 8 to 11 amino acids of the active domain had no elicitor activity but acted as specific, competitive inhibitors in tomato cells. These antagonists suppressed the plant's response to flagellin, crude bacterial extracts and living bacterial cells. Thus, plants have a highly sensitive and selective perception system for the flagellin of motile eubacteria.

CERK1, a LysM receptor kinase, is essential for chitin elicitor signaling in Arabidopsis

Abstract: Chitin is a major component of fungal cell walls and serves as a microbe-associated molecular pattern (MAMP) for the detection of various potential pathogens in innate immune systems of both plants and animals. We recently showed that chitin elicitor-binding protein (CEBiP), plasma membrane glycoprotein with LysM motifs, functions as a cell surface receptor for chitin elicitor in rice. The predicted structure of CEBiP does not contain any intracellular domains, suggesting that an additional component(s) is required for signaling through the plasma membrane into the cytoplasm. Here, we identified a receptor-like kinase, designated CERK1, which is essential for chitin elicitor signaling in Arabidopsis. The KO mutants for CERK1 completely lost the ability to respond to the chitin elicitor, including MAPK activation, reactive oxygen species generation, and gene expression. Disease resistance of the KO mutant against an incompatible fungus, Alternaria brassicicola, was partly impaired. Complementation with the WT CERK1 gene showed cerk1 mutations were responsible for the mutant phenotypes. CERK1 is a plasma membrane protein containing three LysM motifs in the extracellular domain and an intracellular Ser/Thr kinase domain with autophosphorylation/myelin basic protein kinase activity, suggesting that CERK1 plays a critical role in fungal MAMP perception in plants.

Jasmonic acid is a signal transducer in elicitor-induced plant cell cultures.

Abstract: To deter pathogenic microorganisms and herbivores, plants have developed an inducible chemical defense system It is known that the induced synthesis of low molecular weight compounds can be provoked by exposing cultured cells to fungal cell wall fragments In this study we show that endogenous jasmonic acid and its methyl ester accumulate rapidly and transiently after treatment of plant cell suspension cultures of Rauvolfia canescens and Eschscholtzia californica with a yeast elicitor Thirty-six plant species tested in cell suspension culture could be elicited with respect to the accumulation of secondary metabolites by exogenously supplied methyl jasmonate Addition of methyl jasmonate initiates de novo transcription of genes, such as phenylalanine ammonia lyase, that are known to be involved in the chemical defense mechanisms of plants These data demonstrate the integral role of jasmonic acid and its derivatives in the intracellular signal cascade that begins with interaction of an elicitor molecule with the plant cell surface and results, ultimately, in the accumulation of secondary compounds