Danger-Associated Peptide Regulates Root Immune Responses and Root Growth by Affecting ROS Formation in Arabidopsis

Abstract

Plant elicitor peptides (Peps) are damage/danger-associated molecular patterns (DAMPs) that are perceived by a pair of receptor-like kinases, PEPR1 and PEPR2, to enhance innate immunity and induce the growth inhibition of root in Arabidopsis thaliana. In this study, we show that PEPR1 and PEPR2 function vitally in roots to regulate the root immune responses when treating the roots with bacterial pathogen Pst DC3000. PEPR2, rather than PEPR1, played a predominant role in the perception of Pep1 in the roots and further triggered a strong ROS accumulation—the substance acts as an antimicrobial agent or as a secondary messenger in plant cells. Consistently, seedlings mutating two major ROS-generating enzyme genes, respiratory burst oxidase homologs D and F (RBOHD and RBOHF), abolished the root ROS accumulation and impaired the growth inhibition of the roots induced by Pep1. Furthermore, we revealed that botrytis-induced kinase 1 (BIK1) physically interacted with PEPRs and RBOHD/F, respectively, and served downstream of the Pep1-PEPRs signaling pathway to regulate Pep1-induced ROS production and root growth inhibition. In conclusion, this study demonstrates a previously unrecognized signaling crosstalk between Pep1 and ROS signaling to regulate root immune response and root growth.

Moonlighting Proteins Shine New Light on Molecular Signaling Niches

“…The PEP1-PEPRs system intersects both with auxin and ROS signaling, inhibiting root growth [ 133 , 134 ]. It is noteworthy that PEP1 and both jasmonic acid and auxin have been shown to stimulate increases in cGMP levels using the FlincG reporter system [ 98 , 125 ].…”

QTL mapping for Fusarium wilt resistance based on the whole-genome resequencing and their association with functional genes in Raphanus sativus

“…In the present study, ve R genes located in the major QTL FoRsR7.1 FOR59 on R07 had variations in DNA sequences, which resulted in diverse amino acid sequences. Both Rs382850 and Rs382860 are homologous to AT1G73080, which encodes a leucine-rich repeat receptor kinase (LRR-RLK) that serves as a receptor for AtPep1 to enhance the innate immune response to pathogen attacks in A. thaliana Yamada et al 2016;Jing et al 2020). The Rs382950 gene belongs to the TIR-NBS-LRR gene family and is homologous to AT5G46450 and AT1G72840 in A. thaliana.…”

Breaking Bad News: Dynamic Molecular Mechanisms of Wound Response in Plants

“…Protein elicitor peptide 1 (Pep1) was extracted from Arabidopsis thaliana lysates ( Huffaker et al, 2006 ) and is the founding member of a gene family in Arabidopsis of eight with various expression patterns under normal and biotic or abiotic stress conditions ( Huffaker and Ryan, 2007 ; Bartels et al, 2013 ; Bartels and Boller, 2015 ). Peps are encoded in the C-terminus of their precursors, PROPEPs, which are found in both monocots and dicots ( Huffaker et al, 2013 ; Lori et al, 2015 ) and play multiple roles in defenses to pathogens, herbivores, and abiotic stresses ( Ross et al, 2014 ; Klauser et al, 2015 ; Yamada et al, 2016 ; Engelsdorf et al, 2018 ; Lee et al, 2018 ; Nakaminami et al, 2018 ; Zheng et al, 2018 ; Jing et al, 2020 ; Zhang and Gleason, 2020 ). Ca 2+ release in mechanically damaged cells activates the cysteine protease metacaspase4 (MC4) to cleave Pep1 from its precursor PROPEP1 within 5 min after wounding ( Hander et al, 2019 ; Zhu et al, 2020 ).…”