scholarly journals Can Actin Depolymerization Actually Result in Increased Plant Resistance to Pathogens?

2018 ◽  
Author(s):  
Hana Krutinová ◽  
Lucie Trdá ◽  
Tetiana Kalachova ◽  
Lucie Lamparová ◽  
Romana Pospíchalová ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
Plant Resistance ◽  
Fungal Pathogen ◽  
Leptosphaeria Maculans ◽  
Bacterial Pathogen ◽  
Isochorismate Synthase ◽  
Actin Depolymerization ◽  
Pathogen Attack ◽  
Plant Pathosystems ◽  
The Relationship

Introductory paragraphThe integrity of the actin cytoskeleton is essential for plant immune signalling1. Consequently, it is generally assumed that actin disruption reduces plant resistance to pathogen attack2-4. However, in a previous study, it was shown that actin depolymerisation triggers the salicylic acid (SA) signalling pathway5, which is interesting because increased SA is associated with enhanced plant resistance to pathogen attack6,7. Here, we attempt to resolve this seeming inconsistency by showing that the relationship between actin depolymerization and plant resistance is more complex than currently thought. We investigate the precise nature of this relationship using two completely different plant pathosystems: i) a model plant (Arabidopsis thaliana) and a bacterial pathogen (Pseudomonas syringae), and ii) an important crop (Brassica napus) and a fungal pathogen (Leptosphaeria maculans). We demonstrate that actin depolymerization induces a dramatic increase in SA levels and that the increased SA is biosynthesized by the isochorismate synthase pathway. In both pathosystems, this phenomenon leads to increased plant resistance.

scholarly journals A Maize (Zea mays L.) BIK1-Like Receptor-Like Cytoplasmic Kinase Contributes to Disease Resistance

2021 ◽  
Author(s):  
Weiran Li ◽  
Chao-Jan Liao ◽  
Burt H. Bluhm ◽  
Tesfaye Mengiste ◽  
Charles P. Woloshuk
Keyword(s):  
Zea Mays ◽  
Protein Kinase ◽  
Pseudomonas Syringae ◽  
Plant Resistance ◽  
Fungal Pathogen ◽  
Sequence Similarity ◽  
Bacterial Pathogen ◽  
Protein Kinase Activity ◽  
Ear Rot

AbstractReceptor-like cytoplasmic kinases (RLCKs) form a large subfamily of proteins in plants. RLCKs are known to regulate plant immunity to bacterial and fungal pathogens. In this study, we analyzed the genome-wide complement of maize RLCK genes and conducted detailed studies on one maize RLCK. The maize genome encodes 192 RLCKs that largely mirror the RLCK family in other plants. Previous studies implicated Arabidopsis BOTRYTIS INDUCED KINASE1 (BIK1) and TOMATO PROTEIN KINASE 1b (TPK1b) in plant resistance to the bacterial pathogen Pseudomonas syringae and the fungal pathogen Botrytis cinerea. A novel maize RLCK, Zea Mays BIK1-LIKE KINASE 1 (ZmBLK1), was identified based on sequence similarity to the tomato and Arabidopsis RLCKs. We demonstrated that ZmBLK1 displays protein kinase activity in vitro and the protein localizes to the plasma membrane. Importantly, expression of ZmBLK1 partially rescued the growth and disease phenotypes of the Arabidopsis bik1 mutant plants. The expression of ZmBLK1 was induced in maize at 12 h after inoculation with Clavibacter michiganensis subsp. nebraskensis (CMN), the bacterial pathogen causing Goss’s wilt. Interestingly, overexpression of ZmBLK1 in transgenic maize increased resistance to CMN but did not impact resistance to Aspergillus ear rot caused by the fungal pathogen Aspergillus flavus and the associated aflatoxin contamination. These findings support our hypothesis that ZmBLK1 contributes to plant resistance to bacterial pathogens likely by modulating events early after pathogen infection, implying that the protein may interact with other membrane proteins early in the immune response pathway.

scholarly journals Isolation of New Arabidopsis Mutants With Enhanced Disease Susceptibility to Pseudomonas syringae by Direct Screening

Genetics ◽  
1998 ◽  
Vol 149 (2) ◽  
pp. 537-548
Author(s):  
Sigrid M Volko ◽  
Thomas Boller ◽  
Frederick M Ausubel
Keyword(s):  
Pseudomonas Syringae ◽  
Fungal Pathogen ◽  
Systemic Acquired Resistance ◽  
Disease Susceptibility ◽  
Acquired Resistance ◽  
Bacterial Pathogen ◽  
Avirulent Strain ◽  
Resistance Response ◽  
Arabidopsis Mutants ◽  
Pathogen Response

Abstract To identify plant defense components that are important in restricting the growth of virulent pathogens, we screened for Arabidopsis mutants in the accession Columbia (carrying the transgene BGL2-GUS) that display enhanced disease susceptibility to the virulent bacterial pathogen Pseudomonas syringae pv. maculicola (Psm) ES4326. Among six (out of a total of 11 isolated) enhanced disease susceptibility (eds) mutants that were studied in detail, we identified one allele of the previously described npr1/nim1/sai1 mutation, which is affected in mounting a systemic acquired resistance response, one allele of the previously identified EDS5 gene, and four EDS genes that have not been previously described. The six eds mutants studied in detail (npr1-4, eds5-2, eds10-1, eds11-1, eds12-1, and eds13-1) displayed different patterns of enhanced susceptibility to a variety of phytopathogenic bacteria and to the obligate biotrophic fungal pathogen Erysiphe orontii, suggesting that particular EDS genes have pathogen-specific roles in conferring resistance. All six eds mutants retained the ability to mount a hypersensitive response and to restrict the growth of the avirulent strain Psm ES4326/avrRpt2. With the exception of npr1-4, the mutants were able to initiate a systemic acquired resistance (SAR) response, although enhanced growth of Psm ES4326 was still detectable in leaves of SAR-induced plants. The data presented here indicate that eds genes define a variety of components involved in limiting pathogen growth, that many additional EDS genes remain to be discovered, and that direct screens for mutants with altered susceptibility to pathogens are helpful in the dissection of complex pathogen response pathways in plants.

scholarly journals Hormonal Responses to Susceptible, Intermediate, and Resistant Interactions in the Brassica napus–Leptosphaeria maculans Pathosystem

2021 ◽  
Vol 22 (9) ◽  
pp. 4714
Author(s):  
Cunchun Yang ◽  
W. G. Dilantha Fernando
Keyword(s):  
Brassica Napus ◽  
Plant Defense ◽  
Fungal Pathogen ◽  
Durable Resistance ◽  
Leptosphaeria Maculans ◽  
Hormone Signaling ◽  
Hormonal Responses ◽  
Microbe Interactions ◽  
Quantitative Analyses ◽  
The Relationship

Hormone signaling plays a pivotal role in plant–microbe interactions. There are three major phytohormones in plant defense: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). The activation and trade-off of signaling between these three hormones likely determines the strength of plant defense in response to pathogens. Here, we describe the allocation of hormonal signaling in Brassica napus against the fungal pathogen Leptosphaeria maculans. Three B. napus genotypes (Westar, Surpass400, and 01-23-2-1) were inoculated with two L. maculans isolates (H75 8-1 and H77 7-2), subsequently exhibiting three levels of resistance: susceptible, intermediate, and resistant. Quantitative analyses suggest that the early activation of some SA-responsive genes, including WRKY70 and NPR1, contribute to an effective defense against L. maculans. The co-expression among factors responding to SA/ET/JA was also observed in the late stage of infection. The results of conjugated SA measurement also support that early SA activation plays a crucial role in durable resistance. Our results demonstrate the relationship between the onset patterns of certain hormone regulators and the effectiveness of the defense of B. napus against L. maculans.

scholarly journals In planta bacterial multi-omics analysis illuminates regulatory principles underlying plant-pathogen interactions

2019 ◽  
Author(s):  
Tatsuya Nobori ◽  
Yiming Wang ◽  
Jingni Wu ◽  
Sara Christina Stolze ◽  
Yayoi Tsuda ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Pseudomonas Syringae ◽  
Protein Level ◽  
Plant Pathogens ◽  
Plant Immunity ◽  
Bacterial Pathogen ◽  
Bacterial Virulence ◽  
In Planta ◽  
Bacterial Gene ◽  
Global Food Security

AbstractUnderstanding how gene expression is regulated in plant pathogens is crucial for pest control and thus global food security. An integrated understanding of bacterial gene regulation in the host is dependent on multi-omic datasets, but these are largely lacking. Here, we simultaneously characterized the transcriptome and proteome of a foliar bacterial pathogen, Pseudomonas syringae, in Arabidopsis thaliana and identified a number of bacterial processes influenced by plant immunity at the mRNA and the protein level. We found instances of both concordant and discordant regulation of bacterial mRNAs and proteins. Notably, the tip component of bacterial type III secretion system was selectively suppressed by the plant salicylic acid pathway at the protein level, suggesting protein-level targeting of the bacterial virulence system by plant immunity. Furthermore, gene co-expression analysis illuminated previously unknown gene regulatory modules underlying bacterial virulence and their regulatory hierarchy. Collectively, the integrated in planta bacterial omics approach provides molecular insights into multiple layers of bacterial gene regulation that contribute to bacterial growth in planta and elucidate the role of plant immunity in controlling pathogens.

scholarly journals Degeneration of hrpZ gene in Pseudomonas syringae pv. tabaci to evade tobacco defence: an arms race between tobacco and its bacterial pathogen

2011 ◽  
Vol 12 (7) ◽  
pp. 709-714 ◽  
Author(s):  
KAZUHIKO TSUNEMI ◽  
FUMIKO TAGUCHI ◽  
MIZURI MARUTANI ◽  
MEGUMI WATANABE-SUGIMOTO ◽  
YOSHISHIGE INAGAKI ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
Bacterial Pathogen ◽  
Arms Race

scholarly journals A 2′-O-Methyltransferase Responsible for Transfer RNA Anticodon Modification Is Pivotal for Resistance to Pseudomonas syringae DC3000 in Arabidopsis

2018 ◽  
Vol 31 (12) ◽  
pp. 1323-1336 ◽  
Author(s):  
Vicente Ramírez ◽  
Beatriz González ◽  
Ana López ◽  
Maria Jose Castelló ◽  
Maria José Gil ◽  
...  
Keyword(s):  
Disease Resistance ◽  
Pseudomonas Syringae ◽  
Bacterial Pathogen ◽  
Transfer Rna ◽  
Resistance Response ◽  
Chemical Structures ◽  
Trna Modifications ◽  
Trna Species ◽  
Living Organisms ◽  
And Function

Transfer RNA (tRNA) is the most highly modified class of RNA species in all living organisms. Recent discoveries have revealed unprecedented complexity in the tRNA chemical structures, modification patterns, regulation, and function, suggesting that each modified nucleoside in tRNA may have its own specific function. However, in plants, our knowledge of the role of individual tRNA modifications and how they are regulated is very limited. In a genetic screen designed to identify factors regulating disease resistance in Arabidopsis, we identified SUPPRESSOR OF CSB3 9 (SCS9). Our results reveal SCS9 encodes a tRNA methyltransferase that mediates the 2′-O-ribose methylation of selected tRNA species in the anticodon loop. These SCS9-mediated tRNA modifications enhance susceptibility during infection with the virulent bacterial pathogen Pseudomonas syringae DC3000. Lack of such tRNA modification, as observed in scs9 mutants, specifically dampens plant resistance against DC3000 without compromising the activation of the salicylic acid signaling pathway or the resistance to other biotrophic pathogens. Our results support a model that gives importance to the control of certain tRNA modifications for mounting an effective disease resistance in Arabidopsis toward DC3000 and, therefore, expands the repertoire of molecular components essential for an efficient disease resistance response.

scholarly journals Cysteine protease RD21A regulated by E3 ligase SINAT4 is required for drought-induced resistance to Pseudomonas syringae in Arabidopsis

2020 ◽  
Vol 71 (18) ◽  
pp. 5562-5576
Author(s):  
Yi Liu ◽  
Kunru Wang ◽  
Qiang Cheng ◽  
Danyu Kong ◽  
Xunzhong Zhang ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
Cysteine Protease ◽  
Plant Immunity ◽  
Stomatal Closure ◽  
Bacterial Pathogen ◽  
E3 Ligase ◽  
Biotic Stresses ◽  
Ubiquitin E3 Ligase ◽  
Induced Immunity

Abstract Plants can be simultaneously exposed to multiple stresses. The interplay of abiotic and biotic stresses may result in synergistic or antagonistic effects on plant development and health. Temporary drought stress can stimulate plant immunity; however, the molecular mechanism of drought-induced immunity is largely unknown. In this study, we demonstrate that cysteine protease RD21A is required for drought-induced immunity. Temporarily drought-treated wild-type Arabidopsis plants became more sensitive to the bacterial pathogen-associated molecular pattern flg22, triggering stomatal closure, which resulted in increased resistance to Pseudomonas syringae pv. tomato DC3000 (Pst-DC3000). Knocking out rd21a inhibited flg22-triggered stomatal closure and compromised the drought-induced immunity. Ubiquitin E3 ligase SINAT4 interacted with RD21A and promoted its degradation in vivo. The overexpression of SINAT4 also consistently compromised the drought-induced immunity to Pst-DC3000. A bacterial type III effector, AvrRxo1, interacted with both SINAT4 and RD21A, enhancing SINAT4 activity and promoting the degradation of RD21A in vivo. Therefore, RD21A could be a positive regulator of drought-induced immunity, which could be targeted by pathogen virulence effectors during pathogenesis.

Sign in / Sign up

Export Citation Format

Share Document