scholarly journals The Antifungal Effects of Citral on Magnaporthe oryzae Occur via Modulation of Chitin Content as Revealed by RNA-Seq Analysis

2021 ◽  
Vol 7 (12) ◽  
pp. 1023
Author(s):  
Xingchen Song ◽  
Qijun Zhao ◽  
Aiai Zhou ◽  
Xiaodong Wen ◽  
Ming Li ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Amino Sugar ◽  
Cell Wall Integrity ◽  
Rna Seq ◽  
Chitin Synthesis ◽  
Nucleotide Sugar ◽  
Qpcr Analysis ◽  
Antifungal Effects ◽  
Glucose Synthesis

The natural product citral has previously been demonstrated to possess antifungal activity against Magnaporthe oryzae. The purpose of this study was to screen and annotate genes that were differentially expressed (DEGs) in M. oryzae after treatment with citral using RNA sequencing (RNA-seq). Thereafter, samples were reprepared for quantitative real-time PCR (RT-qPCR) analysis verification of RNA-seq data. The results showed that 649 DEGs in M. oryzae were significantly affected after treatment with citral (100 μg/mL) for 24 h. Kyoto Encyclopedia of Genes and Genomes (KEGG) and a gene ontology (GO) analysis showed that DEGs were mainly enriched in amino sugar and nucleotide sugar metabolic pathways, including the chitin synthesis pathway and UDP sugar synthesis pathway. The results of the RT-qPCR analysis also showed that the chitin present in M. oryzae might be degraded to chitosan, chitobiose, N-acetyl-D-glucosamine, and β-D-fructose-6-phosphate following treatment with citral. Chitin degradation was indicated by damaged cell-wall integrity. Moreover, the UDP glucose synthesis pathway was involved in glycolysis and gluconeogenesis, providing precursors for the synthesis of polysaccharides. Galactose-1-phosphate uridylyltransferase, which is involved in the regulation of UDP-α-D-galactose and α-D-galactose-1-phosphate, was downregulated. This would result in the inhibition of UDP glucose (UDP-Glc) synthesis, a reduction in cell-wall glucan content, and the destruction of cell-wall integrity.

scholarly journals A Putative MAP Kinase Kinase Kinase, MCK1, Is Required for Cell Wall Integrity and Pathogenicity of the Rice Blast Fungus, Magnaporthe oryzae

2008 ◽  
Vol 21 (5) ◽  
pp. 525-534 ◽  
Author(s):  
Junhyun Jeon ◽  
Jaeduk Goh ◽  
Sungyong Yoo ◽  
Myoung-Hwan Chi ◽  
Jaehyuk Choi ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Insertional Mutagenesis ◽  
Turgor Pressure ◽  
Cell Wall Integrity ◽  
Mitogen Activated Protein Kinase ◽  
Targeted Disruption ◽  
Disease Symptoms ◽  
Mitogen Activated Protein ◽  
Protein Kinase Kinase

Insertional mutagenesis of Magnaporthe oryzae led to the identification of MCK1, a pathogenicity gene predicted to encode mitogen-activated protein kinase kinase kinase (MAPKKK) homologous to BCK1 in Saccharomyces cerevisiae. Targeted disruption of MCK1 resulted in the fungus undergoing autolysis and showing hypersensitivity to cell-wall-degrading enzyme. The mck1 produced significantly reduced numbers of conidia and developed appressoria in a slightly retarded manner compared with the wild type. Appressorium of the mck1 mutant was unable to penetrate into plant tissues, thereby rendering the mutant nonpathogenic. Cytorrhysis assay and monitoring of lipid mobilization suggested that the appressorial wall was altered, presumably affecting the level of turgor pressure within appressorium. Furthermore, the mck1 mutant failed to grow inside plant tissue. Complementation of the mutated gene restored its ability to cause disease symptoms, demonstrating that MCK1 is required for fungal pathogenicity. Taken together, our results suggest that MCK1 is an MAPKKK involved in maintaining cell wall integrity of M. oryzae, and that remodeling of the cell wall in response to host environments is essential for fungal pathogenesis.

scholarly journals Comparative secretome of Magnaporthe oryzae identified proteins involved in virulence and cell wall integrity

2020 ◽  
Author(s):  
Ning Liu ◽  
Linlu Qi ◽  
Manna Huang ◽  
Deng Chen ◽  
Changfa Yin ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Fungal Pathogens ◽  
Protein Localization ◽  
Potential Effect ◽  
Cell Wall Integrity ◽  
Blast Disease ◽  
Secreted Proteins ◽  
Interspecies Interactions ◽  
Fungal Virulence

AbstractPlant fungal pathogens secrete numerous proteins into the apoplast at the plant–fungus contact sites to facilitate colonization. Only a few secreted proteins were functionally characterized in Magnaporthe oryzae, the fungal pathogen causing rice blast disease worldwide. ALG3 is an α-1, 3-mannosyltransferase function in N-glycan synthesis for secreted N-glycosylated proteins, and the Δalg3 mutants show strong defects in cell wall integrity and fungal virulence, indicating a potential effect on the secretion of multiple proteins. In this study, we compared the secretome of wild type and Δalg3 mutants, and identified 51 proteins that require ALG3 for proper secretion. These are predicted to be involved in metabolic processes, interspecies interactions, cell wall organization, and response to chemicals. The tested secreted proteins localized at the apoplast region surrounding the fungal infection hyphae. Moreover, the N-glycosylation of candidate proteins was significantly changed in the Δalg3 mutant, leading to the reduction of protein secretion and abnormal protein localization. Furthermore, we tested the function of two genes, one is a previously reported M. oryzae gene Invertase 1 (INV1) encoding a secreted invertase, and the other one is a gene encoding an Acid mammalian chinitase (AMCase). The fungal virulence was significantly reduced and the cell wall integrity was altered in the Δinv1 and Δamcase mutant strains. Elucidation of the comparative secretome of M. oryzae improves our understanding of the proteins that require ALG3 for secretion, and of their function in fungal virulence and cell wall integrity.

scholarly journals Shedding light on autophagy coordinating with cell wall integrity signaling to govern pathogenicity of Magnaporthe oryzae

Autophagy ◽  
2019 ◽  
Vol 16 (5) ◽  
pp. 900-916 ◽  
Author(s):  
Ziyi Yin ◽  
Wanzhen Feng ◽  
Chen Chen ◽  
Jiayun Xu ◽  
Ying Li ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Cell Wall Integrity

scholarly journals Crosstalk between calcineurin and the cell wall integrity pathways prevents chitin overexpression in Candida albicans

2021 ◽  
Author(s):  
Alessandra da Silva Dantas ◽  
Filomena Nogueira ◽  
Keunsook K. Lee ◽  
Louise A. Walker ◽  
Matt Edmondson ◽  
...  
Keyword(s):  
Cell Wall ◽  
Candida Albicans ◽  
Antifungal Drugs ◽  
Cell Wall Integrity ◽  
Yeast Cells ◽  
Outer Cell ◽  
Chitin Synthesis ◽  
Simultaneous Activation ◽  
Glucan Synthesis ◽  
Calcineurin Pathway

Echinocandins such as caspofungin are front line antifungal drugs that compromise β-1,3 glucan synthesis in the cell wall. Recent reports have shown that fungal cells can resist killing by caspofungin by up-regulation of chitin synthesis, thereby sustaining cell wall integrity. When echinocandins are removed, the chitin content of cells quickly returns to basal levels, suggesting that there is a fitness cost associated with having elevated levels of chitin in the cell wall. We show here that simultaneous activation of the calcineurin and CWI pathways generates a sub-population of Candida albicans yeast cells that have supra-normal chitin levels interspersed throughout the inner and outer cell wall, and that these cells are non-viable, perhaps due to loss of wall elasticity required for cell expansion and growth. Mutations in the Ca2+-calcineurin pathway prevented the formation of these non-viable super high chitin cells by negatively regulating chitin synthesis driven by the CWI pathway. The Ca2+-calcineurin pathway may therefore act as an attenuator that prevents the overproduction of chitin by coordinating both chitin upregulation and negative regulation of the CWI signaling pathway.

scholarly journals R-SNARE Homolog MoSec22 Is Required for Conidiogenesis, Cell Wall Integrity, and Pathogenesis of Magnaporthe oryzae

PLoS ONE ◽  
2010 ◽  
Vol 5 (10) ◽  
pp. e13193 ◽  
Author(s):  
Wenwen Song ◽  
Xianying Dou ◽  
Zhongqiang Qi ◽  
Qi Wang ◽  
Xing Zhang ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Cell Wall Integrity

scholarly journals Penetration Peg Formation and Invasive Hyphae Development Require Stage-Specific Activation of MoGTI1 in Magnaporthe oryzae

2016 ◽  
Vol 29 (1) ◽  
pp. 36-45 ◽  
Author(s):  
Yang Li ◽  
Guanghui Wang ◽  
Jin-Rong Xu ◽  
Cong Jiang
Keyword(s):  
Gene Expression ◽  
Cell Wall ◽  
Protein Kinase ◽  
Magnaporthe Oryzae ◽  
Phosphorylation Site ◽  
Cell Wall Integrity ◽  
Invasive Growth ◽  
Appressorium Formation ◽  
Plant Infection ◽  
Cdk Phosphorylation

The hemibiotrophic pathogen Magnaporthe oryzae causes one of the most destructive diseases in cultivated rice. Complex infection-related morphogenesis and production of various effectors are known to be important for successful colonization and disease development. In this study, we characterized the activation of the MoGTI1 transcription factor and its role in infection-related morphogenesis and effector gene expression. The Mogti1 mutant was nonpathogenic, although it was normal in appressorium formation and turgor generation. Close examination showed that Mogti1 was defective in penetration and growth of normal invasive hyphae. Deletion of MoGTI1 affected the expression of the majority of effector genes. The expression of MoGti1 appeared to be controlled by the Mps1 but not Pmk1 mitogen-activated protein kinase (MAPK), and the mps1 and Mogti1 mutants had similar phenotypes in plant infection and cell wall integrity defects. However, lack of MAPK phosphorylation sites and dispensability of the putative MAPK docking site suggested that MoGti1 is not a direct target of Mps1. Site-specific mutagenesis analyses showed that the putative protein kinase A phosphorylation site was not essential for localization of MoGti1 to the nucleus but important for its normal function. Although the cyclin-dependent kinase (CDK) phosphorylation site of MoGti1 is dispensable during vegetative growth and appressorium formation, the S77A mutation affected penetration and invasive growth. Localization of MoGti1S77A-green fluorescent protein to the nucleus in late stages of appressorium formation and during invasive growth was not observed, suggesting a stage-specific CDK phosphorylation of MoGti1. Overall, our data indicate that Mps1 may indirectly regulate the expression of MoGti1 in maintaining cell wall integrity, conidiation, and plant infection. MoGti1 is likely a stage-specific target of CDK and plays a crucial role in effector gene expression and morphogenesis related to the development of penetration pegs and invasive hyphae.

scholarly journals Balancing of the mitotic exit network and cell wall integrity signaling governs the development and pathogenicity in Magnaporthe oryzae

2021 ◽  
Vol 17 (1) ◽  
pp. e1009080
Author(s):  
Wanzhen Feng ◽  
Ziyi Yin ◽  
Haowen Wu ◽  
Peng Liu ◽  
Xinyu Liu ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Division ◽  
Magnaporthe Oryzae ◽  
Wall Stress ◽  
Mitotic Exit ◽  
Cellular Growth ◽  
Cell Wall Integrity ◽  
Fungal Cell ◽  
Blast Fungus ◽  
Mitotic Exit Network

The fungal cell wall plays an essential role in maintaining cell morphology, transmitting external signals, controlling cell growth, and even virulence. Relaxation and irreversible stretching of the cell wall are the prerequisites of cell division and development, but they also inevitably cause cell wall stress. Both Mitotic Exit Network (MEN) and Cell Wall Integrity (CWI) are signaling pathways that govern cell division and cell stress response, respectively, how these pathways cross talk to govern and coordinate cellular growth, development, and pathogenicity remains not fully understood. We have identified MoSep1, MoDbf2, and MoMob1 as the conserved components of MEN from the rice blast fungus Magnaporthe oryzae. We have found that blocking cell division results in abnormal CWI signaling. In addition, we discovered that MoSep1 targets MoMkk1, a conserved key MAP kinase of the CWI pathway, through protein phosphorylation that promotes CWI signaling. Moreover, we provided evidence demonstrating that MoSep1-dependent MoMkk1 phosphorylation is essential for balancing cell division with CWI that maintains the dynamic stability required for virulence of the blast fungus.

Sign in / Sign up

Export Citation Format

Share Document