APD1, the unique member of Arabidopsis AP2 family influences systemic acquired resistance and ethylene-jasmonic acid signaling

The Arabidopsis enhanced disease susceptibility 4 (eds4) mutation causes enhanced susceptibility to infection by the bacterial pathogen Pseudomonas syringae pv. Maculicola ES4326 (Psm ES4326). Gene-for-gene resistance to bacteria carrying the avirulence gene avrRpt2 is not significantly affected by eds4. Plants homozygous for eds4 exhibit reduced expression of the pathogenesis-related gene PR-1 after infection by Psm ES4326, weakened responses to treatment with the signal molecule salicylic acid (SA), impairment of the systemic acquired resistance response, and reduced accumulation of SA after infection with Psm ES4326. These phenotypes indicate that EDS4 plays a role in SA-dependent signaling. SA has been shown to have a negative effect on activation of gene expression by the signal molecule jasmonic acid (JA). Two mutations that cause reduced SA levels, eds4 and pad4, cause heightened responses to inducers of JA-dependent gene expression, providing genetic evidence to support the idea that SA interferes with JA-dependent signaling. Two possible working models of the role of EDS4 in governing activation of defense responses are presented.

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Disclosure of salicylic acid and jasmonic acid-responsive genes provides a molecular tool for deciphering stress responses in soybean

Scientific Reports ◽

10.1038/s41598-021-00209-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sebastian F. Beyer ◽

Paloma Sánchez Bel ◽

Victor Flors ◽

Holger Schultheiss ◽

Uwe Conrath ◽

...

Keyword(s):

Salicylic Acid ◽

Jasmonic Acid ◽

Stress Responses ◽

Systemic Acquired Resistance ◽

Marker Gene ◽

Acquired Resistance ◽

Wound Response ◽

Marker Genes ◽

Biotrophic Pathogens ◽

Gene Transcripts

AbstractHormones orchestrate the physiology of organisms. Measuring the activity of defense hormone-responsive genes can help understanding immune signaling and facilitate breeding for plant health. However, different from model species like Arabidopsis, genes that respond to defense hormones salicylic acid (SA) and jasmonic acid (JA) have not been disclosed in the soybean crop. We performed global transcriptome analyses to fill this knowledge gap. Upon exogenous application, endogenous levels of SA and JA increased in leaves. SA predominantly activated genes linked to systemic acquired resistance and defense signaling whereas JA mainly activated wound response-associated genes. In general, SA-responsive genes were activated earlier than those responding to JA. Consistent with the paradigm of biotrophic pathogens predominantly activating SA responses, free SA and here identified most robust SA marker genes GmNIMIN1, GmNIMIN1.2 and GmWRK40 were induced upon inoculation with Phakopsora pachyrhizi, whereas JA marker genes did not respond to infection with the biotrophic fungus. Spodoptera exigua larvae caused a strong accumulation of JA-Ile and JA-specific mRNA transcripts of GmBPI1, GmKTI1 and GmAAT whereas neither free SA nor SA-marker gene transcripts accumulated upon insect feeding. Our study provides molecular tools for monitoring the dynamic accumulation of SA and JA, e.g. in a given stress condition.

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Disclosure of Salicylic Acid and Jasmonic Acid-responsive Genes Provides a Molecular Tool for Deciphering Stress Responses in Soybean

10.21203/rs.3.rs-579376/v1 ◽

2021 ◽

Author(s):

Sebastian F. Beyer ◽

Paloma Sánchez Bel ◽

Victor Flors ◽

Holger Schutheiss ◽

Uwe Conrath ◽

...

Keyword(s):

Salicylic Acid ◽

Jasmonic Acid ◽

Stress Responses ◽

Systemic Acquired Resistance ◽

Marker Gene ◽

Acquired Resistance ◽

Wound Response ◽

Marker Genes ◽

Biotrophic Pathogens ◽

Gene Transcripts

Abstract Hormones orchestrate the physiology of organisms. Measuring the activity of defense hormone-responsive genes can help understanding immune signaling and facilitate breeding for plant health. However, different from model species like Arabidopsis, genes that respond to defense hormones salicylic acid (SA) and jasmonic acid (JA) have not been disclosed in the soybean crop. We performed global transcriptome analyses to fill this knowledge gap. Upon exogenous application, endogenous levels of SA and JA increased in leaves. SA predominantly activated genes linked to systemic acquired resistance and defense signaling whereas JA mainly activated wound response-associated genes. In general, SA-responsive genes were activated earlier than those responding to JA. Consistent with the paradigm of biotrophic pathogens predominantly activating SA responses, free SA and here identified most robust SA marker genes GmNIMIN1, GmNIMIN1.2 and GmWRK40 were induced upon inoculation with Phakopsora pachyrhizi, whereas JA marker genes did not respond to infection with the biotrophic fungus. Spodoptera exigua larvae caused a strong accumulation of JA-Ile and JA-specific mRNA transcripts of GmBPI1, GmKTI1 and GmAAT whereas neither free SA nor SA-marker gene transcripts accumulated upon insect feeding. Our study provides molecular tools for monitoring the dynamic accumulation of SA and JA, e.g. in a given stress condition.

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Local jasmonic acid cues drive systemic acquired resistance signal generation

10.1101/2021.01.20.427489 ◽

2021 ◽

Author(s):

Jennifer Sales ◽

Elisabeth Pabst ◽

Marion Wenig ◽

Heiko H. Breitenbach ◽

Gerardo Perez ◽

...

Keyword(s):

Jasmonic Acid ◽

Systemic Acquired Resistance ◽

Acquired Resistance ◽

Crop Protection ◽

Innate Immune ◽

Signal Generation ◽

Trade Off ◽

Legume Lectin ◽

Biotrophic Pathogens ◽

Immune Pathways

AbstractThe phytohormones salicylic acid (SA) and jasmonic acid (JA) promote two, mutually antagonistic immune pathways respectively protecting plants from biotrophic pathogens and necrotrophic pathogens or insects. This trade-off largely precludes the exploitation of SA and JA immune components for crop protection, raising the interest in immune signalling components that disrupt SA-JA antagonism. A local pathogen infection primes SA-dependent immunity in systemic tissues. This so-called systemic acquired resistance (SAR) ensures a long-lasting, broad-spectrum disease resistance that is not subject to SA-JA antagonism. Here, we show that two sequence-related LEGUME LECTIN-LIKE PROTEINs (LLPs) promote SAR through spatially separated functions with JA promoting local SAR signal generation through LLP3. In concert with LLP1, which is important for systemic recognition and propagation of SAR signals, LLP3 promotes both SA-dependent SAR and JA-mediated immunity. Thus, exploitation of LLP-associated signalling cues might allow application of plant innate immune signals to promote (crop) plant health.

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Induced Systemic Protection Against Tomato Late Blight Elicited by Plant Growth-Promoting Rhizobacteria

Phytopathology ◽

10.1094/phyto.2002.92.12.1329 ◽

2002 ◽

Vol 92 (12) ◽

pp. 1329-1333 ◽

Cited By ~ 165

Author(s):

Zhinong Yan ◽

M. S. Reddy ◽

Choong-Min Ryu ◽

John A. McInroy ◽

Mark Wilson ◽

...

Keyword(s):

Plant Growth ◽

Jasmonic Acid ◽

Late Blight ◽

Systemic Acquired Resistance ◽

Acquired Resistance ◽

Plant Growth Promoting Rhizobacteria ◽

Systemic Resistance ◽

Local Resistance ◽

Plant Growth Promoting ◽

Growth Promoting

Two strains of plant growth-promoting rhizobacteria (PGPR), Bacillus pumilus SE34 and Pseudomonas fluorescens 89B61, elicited systemic protection against late blight on tomato and reduced disease severity by a level equivalent to systemic acquired resistance induced by Phytophthora infestans or induced local resistance by chemical inducer β-amino butyric acid (BABA) in greenhouse assays. Germination of sporangia and zoospores of P. infestans on leaf surfaces of tomato plants treated with the two PGPR strains, pathogen, and chemical BABA was significantly reduced compared with the noninduced control. Induced protection elicited by PGPR, pathogen, and BABA were examined to determine the signal transduction pathways in three tomato lines: salicylic acid (SA)-hydroxylase transgenic tomato (nahG), ethylene insensitive mutants (Nr/Nr), and jasmonic acid insensitive mutants (def1). Results suggest that induced protection elicited by both bacilli and pseudomonad PGPR strains was SA-independent but ethylene- and jasmonic acid-dependent, whereas systemic acquired resistance elicited by the pathogen and induced local resistance by BABA were SA-dependent. The lack of colonization of tomato leaves by strain 89B61 suggests that the observed induced systemic resistance (ISR) was due to systemic protection by strain 89B61 and not attributable to a direct interaction between pathogen and biological control agent. Although strain SE34 was detected on tomato leaves, ISR mainly accounted for the systemic protection with this strain.

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Biochemical basis of systemic acquired resistance induced by different Systemic Acquired Resistance (SAR) elicitors in Brassica cultivars challenge inoculated with downy mildew pathogen

Journal of Applied and Natural Science ◽

10.31018/jans.v13i1.2548 ◽

2021 ◽

Vol 13 (1) ◽

pp. 301-307

Author(s):

Astha ◽

P. S. Sekhon

Keyword(s):

Salicylic Acid ◽

Jasmonic Acid ◽

Disease Control ◽

Downy Mildew ◽

Systemic Acquired Resistance ◽

Acquired Resistance ◽

Fresh Weight ◽

Pathogenesis Related ◽

Cent Disease ◽

Related Proteins

In India, Brassica is attacked by many bacterial, fungal and viral pathogens causing various diseases among which, downy mildew caused by Hyaloperonospora brassicae, an oomycete is the most severe one. The present investigation was conducted to reduce fungicide load on Brassica by testing an alternate method of disease control. Different Systemic Acquired Resistance (SAR) compounds were tested as foliar sprays like Salicylic acid, Jasmonic acid and Bion (Benzothiadiazole-BTH) for inducing resistance in different genotypes of Raya (Brassica juncea) against downy mildew pathogen. Protein content in plants ranged between 43.5 to 57.7 mg/g fresh weight compared to 37.2 mg/g fresh weight in control. Induction of proteins and defense related enzymes was systemic in nature. The SAR compounds also surged the levels of defense related proteins, i.e. Polyphenol oxidase (PPO), Phenylalanine ammonia lyase (PAL) and pathogenesis related Pr- proteins i.e. ?-1,3 glucanase, Peroxidase (POD), from 21 to 130 per cent indicating induction of resistance. Protein profiling of treated Brassica plants was also done electrophoreticaly, which further confirmed the induction of pathogenesis-related proteins ranging from 15- 75 kDa along with some other proteins. Salicylic acid @ 500µM showed best results with 71.27 per cent disease control followed by Jasmonic acid with 69.6 per cent; whereas both, Bion and ?eta amino butyric acid gave almost 63 per cent disease control as compared to control plants. Integration of disease tolerance in Brassica varieties/genotypes combined with prophylactic spray of salicylic acid proved to be very economical for managing downy mildew disease.

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The Transcriptome of Rhizobacteria-Induced Systemic Resistance in Arabidopsis

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2004.17.8.895 ◽

2004 ◽

Vol 17 (8) ◽

pp. 895-908 ◽

Cited By ~ 357

Author(s):

Bas W. M. Verhagen ◽

Jane Glazebrook ◽

Tong Zhu ◽

Hur-Song Chang ◽

L. C. van Loon ◽

...

Keyword(s):

Jasmonic Acid ◽

Broad Spectrum ◽

Plant Pathogens ◽

Systemic Acquired Resistance ◽

Induced Systemic Resistance ◽

Acquired Resistance ◽

Transcriptional Response ◽

Systemic Resistance ◽

Challenge Inoculation ◽

Fluorescent Pseudomonas

Plants develop an enhanced defensive capacity against a broad spectrum of plant pathogens after colonization of the roots by selected strains of nonpathogenic, fluorescent Pseudomonas spp. In Arabidopsis thaliana, this rhizobacteria-induced systemic resistance (ISR) functions independently of salicylic acid but requires responsiveness to the plant hormones jasmonic acid and ethylene. In contrast to pathogen-induced systemic acquired resistance, rhizobacteria-mediated ISR is not associated with changes in the expression of genes encoding pathogenesis-related proteins. To identify ISR-related genes, we surveyed the transcriptional response of over 8,000 Arabidopsis genes during rhizobacteria-mediated ISR. Locally in the roots, ISR-inducing Pseudomonas fluorescens WCS417r bacteria elicited a substantial change in the expression of 97 genes. However, systemically in the leaves, none of the approximately 8,000 genes tested showed a consistent change in expression in response to effective colonization of the roots by WCS417r, indicating that the onset of ISR in the leaves is not associated with detectable changes in gene expression. After challenge inoculation of WCS417r-induced plants with the bacterial leaf pathogen P. syringae pv. tomato DC3000, 81 genes showed an augmented expression pattern in ISR-expressing leaves, suggesting that these genes were primed to respond faster or more strongly upon pathogen attack. The majority of the primed genes was predicted to be regulated by jasmonic acid or ethylene signaling. Priming of pathogen-induced genes allows the plant to react more effectively to the invader encountered, which might explain the broad-spectrum action of rhizobacteria-mediated ISR.

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Probenazole induces systemic acquired resistance in Arabidopsis with a novel type of action

The Plant Journal ◽

10.1046/j.1365-313x.2001.00952.x ◽

2001 ◽

Vol 25 (2) ◽

pp. 149-157 ◽

Cited By ~ 135

Author(s):

Keiko Yoshioka ◽

Hideo Nakashita ◽

Daniel F. Klessig ◽

Isamu Yamaguchi

Keyword(s):

Systemic Acquired Resistance ◽

Acquired Resistance

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