Oligogalacturonides (OGs) released from the plant cell wall are active both as damage-associated molecular patterns (DAMPs) for activation of immune response and regulators growth development. Members Wall-Associated Kinase (WAK) family candidate receptors OGs, due to their ability bind in vitro these oligosaccharides. Because lethality redundancy have hampered study WAKs by reverse genetics, we adopted a chimeric receptor approach elucidate role Arabidopsis WAK1. In test-of-concept study,...

Summary Salicylic acid (SA) is an important regulator of plant defense responses, and a variety Arabidopsis mutants impaired in resistance against bacterial fungal pathogens show defects SA accumulation, perception, or signal transduction. Nevertheless, the role SA‐dependent responses necrotrophic fungi currently unclear. We determined susceptibility set previously identified to pathogen Botrytis cinerea . The rate development B. disease symptoms on primary infected leaves was affected by...

Abstract Oligogalacturonides (OGs) released from plant cell walls by pathogen polygalacturonases induce a variety of host defense responses. Here we show that in Arabidopsis (Arabidopsis thaliana), OGs increase resistance to the necrotrophic fungal Botrytis cinerea independently jasmonate (JA)-, salicylic acid (SA)-, and ethylene (ET)-mediated signaling. Microarray analysis showed about 50% genes regulated OGs, including encoding enzymes involved secondary metabolism, similar change...

Abstract Mitogen-activated protein kinases (MAPKs) are fundamental components of the plant innate immune system. MPK3 and MPK6 Arabidopsis (Arabidopsis thaliana) MAPKs activated by pathogens elicitors such as oligogalacturonides (OGs), which function damage-associated molecular patterns, flg22, a well-known microbe-associated pattern. However, specific contribution to regulation elicitor-induced defense responses is not completely defined. In this work we have investigated roles played these...

Significance Damage-associated molecular patterns (DAMPs), released from host tissues as a consequence of pathogen attack, have been proposed endogenous activators immune responses in both animals and plants. Oligogalacturonides (OGs), oligomers α-1,4–linked galacturonic acid generated vitro by the partial hydrolysis pectin, shown to function potent elicitors immunity when they are applied exogenously plant tissues. However, there is no direct evidence that OGs can be produced vivo or...

Abstract α-1,4-Linked oligogalacturonides (OGs) inhibit auxin-regulated transcriptional activation of arolB-β-glucuronidase (GUS) gene fusion in tobacco (Nicotiana tabacum) leaf explants (D. Bellincampi, M. Cardarelli, D. Zaghi, G. Serino, Salvi, C. Gatz, F. Cervone, M.M. Altamura, P. Costantino, De Lorenzo [1996] Plant Cell 8: 477–487). In this paper we show that inhibition by OGs is very rapid, with a short lag time, and takes place even afterrolB promoter has initiated. also induce...

This paper describes the effect of a plant-derived polygalacturonase-inhibiting protein (PGIP) on activity endopolygalacturonases isolated from fungi. PGIP's is to enhance production oligogalacturonides that are active as elicitors phytoalexin (antibiotic) accumulation and other defense reactions in plants. Only with degree polymerization higher than nine able elicit synthesis soybean cotyledons. In absence PGIP, 1-minute exposure polygalacturonic acid endopolygalacturonase resulted...

Polygalacturonase-inhibiting proteins (PGIPs) are plant that counteract fungal polygalacturonases, which important virulence factors. Like many other defense proteins, PGIPs encoded by gene families, but the roles of individual genes in these families poorly understood. Here, we show Arabidopsis, two tandemly duplicated PGIP upregulated coordinately response to Botrytis cinerea infection, through separate signal transduction pathways. AtPGIP2 expression is mediated jasmonate and requires...

Abstract Oligogalacturonides (OGs) are endogenous elicitors of defense responses released after partial degradation pectin in the plant cell wall. We have previously shown that, Arabidopsis (Arabidopsis thaliana), OGs induce expression PHYTOALEXIN DEFICIENT3 (PAD3) and increase resistance to necrotrophic fungal pathogen Botrytis cinerea independently signaling pathways mediated by jasmonate, salicylic acid, ethylene. Here, we illustrate that rapid induction a variety genes is also...

Polygalacturonase-inhibiting proteins (PGIPs) are plant cell wall that protect plants from fungal invasion. They interact with endo polygalacturonases secreted by phytopathogenic fungi, inhibit their enzymatic activity, and favor the accumulation of oligogalacturonides, which activate defense responses. PGIPs members leucine-rich repeat (LRR) protein family in play crucial roles development, against pathogens, recognition beneficial microbes. Here we report crystal structure at 1.7-Å...

A gene (PGN1) encoding extracellular endopolygalacturonase was isolated from the fungal maize pathogen Cochliobolus carbonum race 1. probe synthesized by polymerase chain reaction using oligonucleotides based on amino acid sequence. Genomic and cDNA copies of were sequenced. The corresponding mRNA present in C. grown pectin but not sucrose as carbon source. single copy PGN1 disrupted homologous integration a plasmid containing an internal fragment gene. Polygalacturonase activity one...

Pectin, one of the main components plant cell wall, is secreted in a highly methyl-esterified form and subsequently deesterified muro by pectin methylesterases (PMEs). In many developmental processes, PMEs are regulated either differential expression or posttranslational control protein inhibitors (PMEIs). PMEIs typically active against ineffective microbial enzymes. Here, we describe three-dimensional structure complex between most abundant PME isoform from tomato fruit (Lycopersicon...

Plant cell walls represent an abundant, renewable source of biofuel and other useful products. The major bottleneck for the industrial scale-up their conversion to simple sugars (saccharification), be subsequently converted by microorganisms into ethanol or products, is recalcitrance enzymatic saccharification. We investigated whether structure pectin that embeds cellulose-hemicellulose network affects exposure cellulose enzymes consequently process Reduction de-methyl-esterified...

Summary Recognition of endogenous molecules acting as ‘damage‐associated molecular patterns’ (DAMPs) is a key feature immunity in both animals and plants. Oligogalacturonides (OGs), i.e. fragments derived from the hydrolysis homogalacturonan, major component pectin are well known class DAMPs that activate protect plants against several microbes. However, hyper‐accumulation OGs severely affects growth, eventually leading to cell death clearly pointing players growth‐defence trade‐off. Here we...

Abstract Fusarium head blight (FHB), caused by graminearum , is one of the most important diseases wheat worldwide, resulting in yield losses and mycotoxin contamination. The molecular mechanisms regulating penetration infection are poorly understood. Beside production, cell wall degradation may play a role development FHB. Many fungal pathogens secrete polygalacturonases (PGs) during early stages infection, plants have evolved polygalacturonase‐inhibiting proteins (PGIPs) to restrict pectin...

Summary The plant cell wall is the barrier that pathogens must overcome to cause a disease, and this end they secrete enzymes degrade various components. Due complexity of these components, several types oligosaccharide fragments may be released during pathogenesis some can act as damage‐associated molecular patterns ( DAMP s). Well‐known s are oligogalacturonides OG s) upon degradation homogalacturonan products cellulose breakdown, i.e. cellodextrins CD We have previously reported four...

Plant immunity against pathogens is achieved through rapid activation of defense responses that occur upon sensing microbe- or damage-associated molecular patterns, respectively referred to as MAMPs and DAMPs. Oligogalacturonides (OGs), linear fragments derived from homogalacturonan hydrolysis by pathogen-secreted cell wall-degrading enzymes, flg22, a 22-amino acid peptide the bacterial flagellin, represent prototypical DAMPs MAMPs, respectively. Both types molecules induce protection...

Summary Polygalacturonase‐inhibiting protein (PGIP) is a cell wall purified from hypocotyls of true bean ( Phaseolus vulgaris L.). PGIP inhibits fungal endopolygalacturonases and considered to be an important factor for plant resistance phytopathogenic fungi (Albersheim Anderson, 1971; Cervone et al. , 1987). The amino acid sequences the N‐terminus one internal tryptic peptide P. cv. Pinto were used design redundant oligonucleotides that successfully utilized as primers in polymerase chain...