Brassica napus Mediator Subunit16 Induces BnMED25- and BnWRKY33-Activated Defense Signaling to Confer Sclerotinia sclerotiorum Resistance

The plant mediator is a highly conserved protein complex that interacts with transcription factors (TFs) and RNA polymerase II (RNAP II) to relay regulatory information during transcription. Plant immune response is one of the biological processes that is orchestrated by this regulatory mechanism. Brassica napus, an important oil crop, is severely attacked by a devastating disease Sclerotinia stem rot. Here, we explored broad-spectrum disease resistant roles of B. napus mediator subunit 16 (BnMED16) and its host defense mechanism against fugal pathogen Sclerotinia sclerotiorum. We found that BnMED16 expression was significantly increased by S. sclerotiorum infection, and its homologous overexpression resulted in rapid and comprehensive defense responses from the beginning to the end. This affected signal transduction with multiple channels including pathogen recognition, intracellular Ca2+ concentration, reactive oxygen species (ROS) accumulation and clearance, and activation of mitogen-activated protein kinase (MAPK) signaling cascades initially. Subsequently, pathogen-/defense-related genes and hormone-responsive pathways were highly activated, which resulted in enhanced cell wall and secretion of defense proteases. Furthermore, the biochemical analysis showed that BnMED16 interacts with BnMED25 and BnWRKY33. Additionally, BnMED25 also interacts with TFs BnMYC2, BnCOI1, and BnEIN3 of the JA/ET signal transduction pathway. Taken together, we proposed a hypothetical model that BnMED16 confers S. sclerotiorum resistance by enhancing BnMED25-mediated JA/ET defense pathways and BnWRKY33-activated defense signaling in B. napus. The BnMED16 overexpressing lines with enhanced broad-spectrum disease resistance could be useful for breeding Sclerotinia-resistant oilseed rape varieties, as well as serving as basis for further strategy development in resistance breeding.

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Molecular Regulation of Host Defense Responses Mediated by Biological Anti-TMV Agent Ningnanmycin

Viruses ◽

10.3390/v11090815 ◽

2019 ◽

Vol 11 (9) ◽

pp. 815 ◽

Cited By ~ 2

Author(s):

Mengnan An ◽

Tao Zhou ◽

Yi Guo ◽

Xiuxiang Zhao ◽

Yuanhua Wu

Keyword(s):

Antiviral Activity ◽

Calcium Binding ◽

Defense Responses ◽

Plant Viruses ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Systemic Resistance ◽

Mitogen Activated Protein ◽

Significant Enrichment ◽

Plant Pathogen Interaction

Ningnanmycin (NNM) belongs to microbial pesticides that display comprehensive antiviral activity against plant viruses. NNM treatment has been shown to efficiently delay or suppress the disease symptoms caused by tobacco mosaic virus (TMV) infection in local-inoculated or systemic-uninoculated tobacco leaves, respectively. However, the underlying molecular mechanism of NNM-mediated antiviral activity remains to be further elucidated. In this study, 414 differentially expressed genes (DEGs), including 383 which were up-regulated and 31 down-regulated, caused by NNM treatment in TMV-infected BY-2 protoplasts, were discovered by RNA-seq. In addition, KEGG analysis indicated significant enrichment of DEGs in the plant–pathogen interaction and MAPK signaling pathway. The up-regulated expression of crucial DEGs, including defense-responsive genes, such as the receptor-like kinase FLS2, RLK1, and the mitogen-activated protein kinase kinase kinase MAPKKK, calcium signaling genes, such as the calcium-binding protein CML19, as well as phytohormone responsive genes, such as the WRKY transcription factors WRKY40 and WRKY70, were confirmed by RT-qPCR. These findings provided valuable insights into the antiviral mechanisms of NNM, which indicated that the agent induces tobacco systemic resistance against TMV via activating multiple plant defense signaling pathways.

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Interaction between Connexin50 and Mitogen-activated Protein Kinase Signaling in Lens Homeostasis

Molecular Biology of the Cell ◽

10.1091/mbc.e08-12-1257 ◽

2009 ◽

Vol 20 (10) ◽

pp. 2582-2592 ◽

Cited By ~ 16

Author(s):

Teresa I. Shakespeare ◽

Caterina Sellitto ◽

Leping Li ◽

Clio Rubinos ◽

Xiaohua Gong ◽

...

Keyword(s):

Signal Transduction ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Signal Transduction Pathways ◽

Gap Junctional Communication ◽

Junctional Communication ◽

Mitogen Activated Protein ◽

Gap Junctional

Both connexins and signal transduction pathways have been independently shown to play critical roles in lens homeostasis, but little is known about potential cooperation between these two intercellular communication systems. To investigate whether growth factor signaling and gap junctional communication interact during the development of lens homeostasis, we examined the effect of mitogen-activated protein kinase (MAPK) signaling on coupling mediated by specific lens connexins by using a combination of in vitro and in vivo assays. Activation of MAPK signaling pathways significantly increased coupling provided by Cx50, but not Cx46, in paired Xenopus laevis oocytes in vitro, as well as between freshly isolated lens cells in vivo. Constitutively active MAPK signaling caused macrophthalmia, cataract, glucose accumulation, vacuole formation in differentiating fibers, and lens rupture in vivo. The specific removal or replacement of Cx50, but not Cx46, ameliorated all five pathological conditions in transgenic mice. These results indicate that MAPK signaling specifically modulates coupling mediated by Cx50 and that gap junctional communication and signal transduction pathways may interact in osmotic regulation during postnatal fiber development.

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Hog1 Mitogen-Activated Protein Kinase (MAPK) Interrupts Signal Transduction between the Kss1 MAPK and the Tec1 Transcription Factor To Maintain Pathway Specificity

Eukaryotic Cell ◽

10.1128/ec.00005-09 ◽

2009 ◽

Vol 8 (4) ◽

pp. 606-616 ◽

Cited By ~ 31

Author(s):

Teresa R. Shock ◽

James Thompson ◽

John R. Yates ◽

Hiten D. Madhani

Keyword(s):

Signal Transduction ◽

Transcription Factor ◽

Protein Kinase ◽

Dna Binding ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Nuclear Accumulation ◽

Hog Pathway ◽

Pathway Activation ◽

Mitogen Activated Protein

ABSTRACT In Saccharomyces cerevisiae, the mating, filamentous growth (FG), and high-osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) signaling pathways share components and yet mediate distinct responses to different extracellular signals. Cross talk is suppressed between the mating and FG pathways because mating signaling induces the destruction of the FG transcription factor Tec1. We show here that HOG pathway activation results in phosphorylation of the FG MAPK, Kss1, and the MAPKK, Ste7. However, FG transcription is not activated because HOG signaling prevents the activation of Tec1. In contrast to the mating pathway, we find that the mechanism involves the inhibition of DNA binding by Tec1 rather than its destruction. We also find that nuclear accumulation of Tec1 is not affected by HOG signaling. Inhibition by Hog1 is apparently indirect since it does not require any of the consensus S/TP MAPK phosphorylation sites on Tec1, its DNA-binding partner Ste12, or the associated regulators Dig1 or Dig2. It also does not require the consensus MAPK sites of the Ste11 activator Ste50, in contrast to a recent proposal for a role for negative feedback in specificity. Our results demonstrate that HOG signaling interrupts the FG pathway signal transduction between the phosphorylation of Kss1 and the activation of DNA binding by Tec1.

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Comparative transcriptomic analysis uncovers the complex genetic network for resistance to Sclerotinia sclerotiorum in Brassica napus

Scientific Reports ◽

10.1038/srep19007 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 56

Author(s):

Jian Wu ◽

Qing Zhao ◽

Qingyong Yang ◽

Han Liu ◽

Qingyuan Li ◽

...

Keyword(s):

Brassica Napus ◽

Differentially Expressed Genes ◽

Sclerotinia Sclerotiorum ◽

Defense Response ◽

Quantitative Resistance ◽

Resistance Breeding ◽

Mapk Signaling ◽

Differentially Expressed ◽

Post Inoculation ◽

Sclerotinia Stem Rot

Abstract Sclerotinia stem rot caused by Sclerotinia sclerotiorum is one of the most devastating diseases in many important crops including Brassica napus worldwide. Quantitative resistance is the only source for genetic improvement of Sclerotinia-resistance in B. napus, but the molecular basis for such a resistance is largely unknown. Here, we performed dynamic transcriptomic analyses to understand the differential defense response to S. sclerotiorum in a resistant line (R-line) and a susceptible line (S-line) of B. napus at 24, 48 and 96 h post-inoculation. Both the numbers of and fold changes in differentially expressed genes in the R-line were larger than those in the S-line. We identified 9001 relative differentially expressed genes in the R-line compared with the S-line. The differences between susceptibility and resistance were associated with the magnitude of expression changes in a set of genes involved in pathogen recognition, MAPK signaling cascade, WRKY transcription regulation, jasmonic acid/ethylene signaling pathways and biosynthesis of defense-related protein and indolic glucosinolate. The results were supported by quantitation of defense-related enzyme activity and glucosinolate contents. Our results provide insights into the complex molecular mechanism of the defense response to S. sclerotiorum in B. napus and for development of effective strategies in Sclerotinia-resistance breeding.

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Exploring the Biological and Molecular Characteristics of resistance to Fludioxonil in Sclerotinia sclerotiorum from soybean in China

Plant Disease ◽

10.1094/pdis-07-20-1621-re ◽

2020 ◽

Author(s):

Feng Zhou ◽

Hai-Yan Hu ◽

Dong-Xiao Li ◽

Li-Guo Tan ◽

Qiang Zhang ◽

...

Keyword(s):

Amino Acid ◽

Sclerotinia Sclerotiorum ◽

Plant Pathogens ◽

Mapk Pathway ◽

Mapk Signaling ◽

Management Program ◽

Mitogen Activated Protein Kinase ◽

Cross Resistance ◽

Molecular Characteristics ◽

Predicted Amino Acid Sequence

Sclerotinia sclerotiorum is one of the most damaging and economically important necrotrophic plant pathogens, infecting more than 400 plant species globally. Although the phenylpyrrole fungicide fludioxonil has high activity against S. sclerotiorum, recent reports have indicated that there is also a substantial potential for the development of fungicide resistance. However, the current study investigating five fludioxonil-resistant laboratory mutants found a significant fitness cost associated with fludioxonil resistance resulting in significantly (p < 0.005) reduced mycelial growth and sclerotia formation on PDA, as well as significantly (p < 0.05) lower pathogenicity on detached tomato leaves, with one mutant, LK-1R, completely losing the capacity to cause infection. In addition, all of the fludioxonil-resistant mutants had significantly (p < 0.05) increased sensitivity to osmotic stress (0.5 M KCl and 1.0 M Glucose), which is consistent with the proposed fludioxonil target sites within the High Osmolarity Glycerol (HOG1) stress response mitogen-activated protein kinase (MAPK) (HOG1-MAPK) signaling transduction pathway. Sequence analysis of six genes from this two-component pathway, including SsHk, SsYpd, SsSk1, SsSk2, SsPbs, and SsHog, revealed several mutations which maybe associated fludioxonil resistance. For example, six separate point mutations were found in the SsHk gene that lead to changes in the predicted amino acid sequence, including A136G, F249V, G353A, E560K, M610K, and K727R. Similarly, the SsPbs gene had three mutations (D34G, S46L, and L337E); the SsSk1 and SsYpd genes two (S53G and A795V, and E67G and Y141H, respectively) and the SsHog and SsSk2 genes one each (V220A and S763P, respectively). To the best of our knowledge, these constitute the first reports of amino acid changes in the proteins of the HOG1-MAPK pathway being associated with fludioxonil resistance in S. sclerotiorum. The study also found a positive cross-resistance between fludioxonil and dimethachlone and procymidone, but none with tebuconazole or carbendazim, indicating that the inclusion of tebuconazole within an integrated pest management program could reduce the risk of fludioxonil developing in field populations of S. sclerotiorum, and ensure the sustainable production of soybeans in China into the future.

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Expression, Subcellular Localization, and Interactions of CPK Family Genes in Maize

International Journal of Molecular Sciences ◽

10.3390/ijms20246173 ◽

2019 ◽

Vol 20 (24) ◽

pp. 6173

Author(s):

Muhammad Hayder Bin Khalid ◽

Muhammad Ali Raza ◽

Hao Qiang Yu ◽

Imran Khan ◽

Fu Ai Sun ◽

...

Keyword(s):

Protein Kinase ◽

Calcium Signaling ◽

Signaling Pathways ◽

Defense Mechanism ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Pcr Analysis ◽

Phylogenetic Groups ◽

Positive Interaction ◽

Cdna Sequences

Calcium-dependent protein kinase (CPKs) is a key player in the calcium signaling pathway to decode calcium signals into various physiological responses. cDNA sequences of 9 ZmCPK genes were successfully cloned from all four phylogenetic groups in maize. qRT-PCR analysis showed the expression variation of these selected genes under abscisic acid (ABA) and calcium chloride (CaCl2) treatment. Due to the presence of N-myristoylation/palmitoylation sites, the selected ZmCPK members were localized in a plasma membrane. To clarify whether ZmCPK, a key player in calcium signaling, interacts with key players of ABA, protein phosphatase 2Cs (PP2Cs) and the SNF1-related protein kinase 2s (SnRK2s) and mitogen-activated protein kinase (MAPK) signaling pathways in maize, we examined the interaction between 9 CPKs, 8 PP2Cs, 5 SnRKs, and 20 members of the MPK family in maize by using yeast two-hybrid assay. Our results showed that three ZmCPKs interact with three different members of ZmSnRKs while four ZmCPK members had a positive interaction with 13 members of ZmMPKs in different combinations. These four ZmCPK proteins are from three different groups in maize. These findings of physical interactions between ZmCPKs, ZmSnRKs, and ZmMPKs suggested that these signaling pathways do not only have indirect influence but also have direct crosstalk that may involve the defense mechanism in maize. The present study may improve the understanding of signal transduction in plants.

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Global Gene Responses of Resistant and Susceptible Sugarcane Cultivars to Acidovorax avenae subsp. avenae Identified Using Comparative Transcriptome Analysis

Microorganisms ◽

10.3390/microorganisms8010010 ◽

2019 ◽

Vol 8 (1) ◽

pp. 10 ◽

Cited By ~ 1

Author(s):

Na Chu ◽

Jing-Ru Zhou ◽

Hua-Ying Fu ◽

Mei-Ting Huang ◽

Hui-Li Zhang ◽

...

Keyword(s):

Signal Transduction ◽

Large Scale ◽

Molecular Mechanisms ◽

Expression Patterns ◽

Defense Responses ◽

Differentially Expressed ◽

Mitogen Activated Protein Kinase ◽

Post Inoculation ◽

Rna Seq ◽

Mitogen Activated Protein

Red stripe disease in sugarcane caused by Acidovorax avenae subsp. avenae (Aaa) is related to serious global losses in yield. However, the underlying molecular mechanisms associated with responses of sugarcane plants to infection by this pathogen remain largely unknown. Here, we used Illumina RNA-sequencing (RNA-seq) to perform large-scale transcriptome sequencing of two sugarcane cultivars to contrast gene expression patterns of plants between Aaa and mock inoculations, and identify key genes and pathways involved in sugarcane defense responses to Aaa infection. At 0–72 hours post-inoculation (hpi) of the red stripe disease-resistant cultivar ROC22, a total of 18,689 genes were differentially expressed between Aaa-inoculated and mock-inoculated samples. Of these, 8498 and 10,196 genes were up- and downregulated, respectively. In MT11-610, which is susceptible to red stripe disease, 15,782 genes were differentially expressed between Aaa-inoculated and mock-inoculated samples and 8807 and 6984 genes were up- and downregulated, respectively. The genes that were differentially expressed following Aaa inoculation were mainly involved in photosynthesis and carbon metabolism, phenylpropanoid biosynthesis, plant hormone signal transduction, and plant–pathogen interaction pathways. Further, qRT-PCR and RNA-seq used for additional validation of 12 differentially expressed genes (DEGs) showed that eight genes in particular were highly expressed in ROC22. These eight genes participated in the biosynthesis of lignin and coumarin, as well as signal transduction by salicylic acid, jasmonic acid, ethylene, and mitogen-activated protein kinase (MAPK), suggesting that they play essential roles in sugarcane resistance to Aaa. Collectively, our results characterized the sugarcane transcriptome during early infection with Aaa, thereby providing insights into the molecular mechanisms responsible for bacterial tolerance.

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Jasmonate-Dependent and COI1-Independent Defense Responses Against Sclerotinia sclerotiorum in Arabidopsis thaliana: Auxin is Part of COI1-Independent Defense Signaling

Plant and Cell Physiology ◽

10.1093/pcp/pcr127 ◽

2011 ◽

Vol 52 (11) ◽

pp. 1941-1956 ◽

Cited By ~ 31

Author(s):

Henrik U. Stotz ◽

Yusuke Jikumaru ◽

Yukihisa Shimada ◽

Eriko Sasaki ◽

Nadja Stingl ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Sclerotinia Sclerotiorum ◽

Defense Responses ◽

Defense Signaling

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Transcriptome analysis reveals defense-related genes and pathways against Xanthomonas campestris pv. vesicatoria in pepper (Capsicum annuum L.)

PLoS ONE ◽

10.1371/journal.pone.0240279 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0240279

Author(s):

Shenghua Gao ◽

Fei Wang ◽

Juntawong Niran ◽

Ning Li ◽

Yanxu Yin ◽

...

Keyword(s):

Transcription Factors ◽

Xanthomonas Campestris ◽

Molecular Mechanisms ◽

Enrichment Analysis ◽

Defense Responses ◽

Mapk Signaling ◽

Functional Enrichment ◽

Differentially Expressed ◽

Mitogen Activated Protein Kinase ◽

Sequencing Platform

Bacterial spot (BS), incited by Xanthomonas campestris pv. vesicatoria (Xcv), is one of the most serious diseases of pepper. For a comparative analysis of defense responses to Xcv infection, we performed a transcriptomic analysis of a susceptible cultivar, ECW, and a resistant cultivar, VI037601, using the HiSeqTM 2500 sequencing platform. Approximately 120.23 G clean bases were generated from 18 libraries. From the libraries generated, a total of 38,269 expressed genes containing 11,714 novel genes and 11,232 differentially expressed genes (DEGs) were identified. Functional enrichment analysis revealed that the most noticeable pathways were plant-pathogen interaction, MAPK signaling pathway—plant, plant hormone signal transduction and secondary metabolisms. 1,599 potentially defense-related genes linked to pattern recognition receptors (PRRs), mitogen-activated protein kinase (MAPK), calcium signaling, and transcription factors may regulate pepper resistance to Xcv. Moreover, after Xcv inoculation, 364 DEGs differentially expressed only in VI037601 and 852 genes in both ECW and VI037601. Many of those genes were classified as NBS-LRR genes, oxidoreductase gene, WRKY and NAC transcription factors, and they were mainly involved in metabolic process, response to stimulus and biological regulation pathways. Quantitative RT-PCR of sixteen selected DEGs further validated the RNA-seq differential gene expression analysis. Our results will provide a valuable resource for understanding the molecular mechanisms of pepper resistance to Xcv infection and improving pepper resistance cultivars against Xcv.

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Regulation of spontaneous and induced resumption of meiosis in mouse oocytes by different intracellular pathways

Reproduction ◽

10.1530/reprod/120.2.377 ◽

2000 ◽

pp. 377-383 ◽

Cited By ~ 13

Author(s):

L Leonardsen ◽

A Wiersma ◽

M Baltsen ◽

AG Byskov ◽

CY Andersen

Keyword(s):

Signal Transduction ◽

Protein Kinase ◽

Protein Kinase A ◽

Mitogen Activated Protein Kinase ◽

Meiotic Maturation ◽

Mouse Oocytes ◽

Mitogen Activated Protein ◽

Dependent Signal ◽

Kinase Pathway ◽

Kinase A

The mitogen-activated protein kinase-dependent and the cAMP-protein kinase A-dependent signal transduction pathways were studied in cultured mouse oocytes during induced and spontaneous meiotic maturation. The role of the mitogen-activated protein kinase pathway was assessed using PD98059, which specifically inhibits mitogen-activated protein kinase 1 and 2 (that is, MEK1 and MEK2), which activates mitogen-activated protein kinase. The cAMP-dependent protein kinase was studied by treating oocytes with the protein kinase A inhibitor rp-cAMP. Inhibition of the mitogen-activated protein kinase pathway by PD98059 (25 micromol l(-1)) selectively inhibited the stimulatory effect on meiotic maturation by FSH and meiosis-activating sterol (that is, 4,4-dimethyl-5alpha-cholest-8,14, 24-triene-3beta-ol) in the presence of 4 mmol hypoxanthine l(-1), whereas spontaneous maturation in the absence of hypoxanthine was unaffected. This finding indicates that different signal transduction mechanisms are involved in induced and spontaneous maturation. The protein kinase A inhibitor rp-cAMP induced meiotic maturation in the presence of 4 mmol hypoxanthine l(-1), an effect that was additive to the maturation-promoting effect of FSH and meiosis-activating sterol, indicating that induced maturation also uses the cAMP-protein kinase A-dependent signal transduction pathway. In conclusion, induced and spontaneous maturation of mouse oocytes appear to use different signal transduction pathways.

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