scholarly journals The CfMK1 Gene Regulates Reproduction, Appressorium Formation, and Pathogenesis in a Pear Anthracnose-Causing Fungus

2022 ◽  
Vol 8 (1) ◽  
pp. 77
Author(s):  
Chaohui Li ◽  
Weibo Sun ◽  
Shulin Cao ◽  
Rongxian Hou ◽  
Xiaogang Li ◽  
...  
Keyword(s):  
Cell Wall ◽  
Germination Rate ◽  
Hyphal Growth ◽  
Pathogenic Fungi ◽  
Mitogen Activated Protein Kinase ◽  
Economic Losses ◽  
Deletion Mutants ◽  
Appressorium Formation ◽  
Mapk Cascades ◽  
Mitogen Activated Protein

Colletotrichum fructicola, the causal agent of pear anthracnose, causes significant annual economic losses. Mitogen-activated protein kinase (MAPK) cascades are highly conserved signal transduction pathways that play a crucial role in mediating cellular responses to environmental and host signals in plant pathogenic fungi. In this study, we identified an ortholog of the FUS3/KSS1-related MAPK gene, CfMK1, and characterized its function in C. fructicola. The Cfmk1 deletion mutants exhibited poorly developed aerial hyphae, autolysis, no conidial mass or perithecia on solid plates. However, the conidiation of the Cfmk1 mutant in PDB liquid medium was normal compared with that of the wild type (WT). Conidia of the Cfmk1 mutant exhibited a reduced germination rate on glass slides or plant surfaces. The Cfmk1 deletion mutants were unable to form appressoria and lost the capacity to penetrate plant epidermal cells. The ability of the Cfmk1 mutants to infect pear leaves and fruit was severely reduced. Moreover, RNA sequencing (RNA-seq) analysis of the WT and Cfmk1 mutant was performed, and the results revealed 1886 upregulated and 1554 downregulated differentially expressed genes (DEGs) in the mutant. The DEGs were significantly enriched in cell wall and pathogenesis terms, which was consistent with the defects of the Cfmk1 mutant in cell wall integrity and plant infection. Overall, our data demonstrate that CfMK1 plays critical roles in the regulation of aerial hyphal growth, asexual and sexual reproduction, autolysis, appressorium formation, and pathogenicity.

scholarly journals Novel Mitogen-Activated Protein Kinase MpkC of Aspergillus fumigatus Is Required for Utilization of Polyalcohol Sugars

2006 ◽  
Vol 5 (11) ◽  
pp. 1934-1940 ◽  
Author(s):  
Guadalupe Reyes ◽  
Angela Romans ◽  
C. Kim Nguyen ◽  
Gregory S. May
Keyword(s):  
Carbon Source ◽  
Aspergillus Fumigatus ◽  
Hyphal Growth ◽  
Mitogen Activated Protein Kinase ◽  
Deletion Mutants ◽  
Mrna Levels ◽  
Hypertonic Stress ◽  
Mitogen Activated Protein ◽  
Stress Oxidative ◽  
Mapk Gene

ABSTRACT The genome of Aspergillus fumigatus has four genes that encode mitogen-activated protein kinases (MAPKs), sakA/hogA, mpkA, mpkB, and mpkC. The functions of the MpkB and MpkC MAPKs are unknown for A. fumigatus and the closely related and genetically amenable species Aspergillus nidulans. mpkC deletion mutants of A. fumigatus were made and their phenotypes characterized. The mpkC deletion mutants were viable and had normal conidial germination and hyphal growth on minimal or complete media. This is in contrast to deletion mutants with deletions in the closely related MAPK gene sakA/hogA that we previously reported had a nitrogen source-dependent germination phenotype. Similarly, the growth of the mpkC deletion mutants was wild type on high-osmolarity medium. Consistent with these two MAP kinase genes regulating different cellular responses, we determined that the mpkC deletion mutants were unable to grow on minimal medium with sorbitol or mannitol as the sole carbon source. This result implicates MpkC signaling in carbon source utilization. Changes in mRNA levels for sakA and mpkC were measured in response to hypertonic stress, oxidative stress, and a shift from glucose to sorbitol to determine if there was overlap in the SakA and MpkC signaling pathways. These studies demonstrated that SakA- and MpkC-dependent patterns of change in mRNA levels are distinct and have minimal overlap in response to these environmental stresses.

scholarly journals MAPK cascades mediating Trichoderma brevicrassum strain TC967 against phytopathogen Rhizoctonia solani

2021 ◽  
Author(s):  
Yi Zhang ◽  
Wen-Ying Zhuang
Keyword(s):  
Cell Wall ◽  
Rhizoctonia Solani ◽  
Biological Control Agent ◽  
Hyphal Growth ◽  
Control Agent ◽  
Mitogen Activated Protein Kinase ◽  
Cell Wall Degrading Enzymes ◽  
Gene Expressions ◽  
Fungal Cell ◽  
Mapk Cascades

Trichoderma brevicrassum strain TC967 is a novel biological control agent (BCA) against the plant pathogen Rhizoctonia solani and promotes plant growth. MAPK (mitogen-activated protein kinase) cascades were involved in biocontrol by Trichoderma, but functions of each MAPK in regulating biocontrol have not been characterized in one Trichoderma. In this study, we assembled and annotated the genome of strain TC967, and identified its three MAPK gene sequences. Functions of Fus3-, Slt2- and Hog1-MAPK in strain TC967 were dissected. The three MAPKs were all involved in hyphal growth. The Hog1-MAPK was essential for conidiation and tolerance to hyperosmotic stress. The Fus3- and Slt2-MAPK both mediated cell-wall integrity (CWI) and activities of chitinase and protease. The Fus3- and Hog1-MAPK mediated response to oxidative stress. Our biocontrol assays demonstrated that the Fus3- and Slt2-MAPK mutants were considerably more effective in disease control than the wild-type strain. RNA-seq analysis revealed that MAPK collectively played a major role in regulating biocontrol-related gene expressions, including of the genes in charge of secondary metabolism, fungal cell wall-degrading enzymes (FCWDEs) and small secreted cysteine-rich proteins (SSCPs).

scholarly journals The MAPKKK CgMck1 Is Required for Cell Wall Integrity, Appressorium Development, and Pathogenicity in Colletotrichum gloeosporioides

Genes ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 543 ◽  
Author(s):  
Yu-Lan Fang ◽  
Li-Ming Xia ◽  
Ping Wang ◽  
Li-Hua Zhu ◽  
Jian-Ren Ye ◽  
...  
Keyword(s):  
Cell Wall ◽  
Vegetative Growth ◽  
Colletotrichum Gloeosporioides ◽  
Mapk Signaling ◽  
Cell Wall Integrity ◽  
Mitogen Activated Protein Kinase ◽  
Extracellular Signals ◽  
Mapk Cascades ◽  
Body Development ◽  
Mitogen Activated Protein

Mitogen-activated protein kinase (MAPK) signaling pathway plays key roles in sensing extracellular signals and transmitting them from the cell membrane to the nucleus in response to various environmental stimuli. A MAPKKK protein CgMck1 in Colletotrichum gloeosporioides was characterized. Phenotypic analyses of the ∆Cgmck1 mutant showed that the CgMck1 was required for vegetative growth, fruiting body development, and sporulation. Additionally, the CgMCK1 deletion mutant showed significant defects in cell wall integrity, and responses to osmotic stresses. The mutant abolished the ability to develop appressorium, and lost pathogenicity to host plants. The ∆Cgmck1 mutant also exhibited a higher sensitivity to antifungal bacterium agent Bacillus velezensis. The deletion mutants of downstream MAPK cascades components CgMkk1 and CgMps1 showed similar defects to the ∆Cgmck1 mutant. In conclusion, CgMck1 is involved in the regulation of vegetative growth, asexual development, cell wall integrity, stresses resistance, and infection morphogenesis in C. gloeosporioides.

scholarly journals Pleiotropic Function of the Putative Zinc-Finger Protein MoMsn2 in Magnaporthe oryzae

2014 ◽  
Vol 27 (5) ◽  
pp. 446-460 ◽  
Author(s):  
Haifeng Zhang ◽  
Qian Zhao ◽  
Xianxian Guo ◽  
Min Guo ◽  
Zhongqiang Qi ◽  
...  
Keyword(s):  
Cell Wall ◽  
Magnaporthe Oryzae ◽  
Stress Responses ◽  
Zinc Finger Protein ◽  
Affinity Purification ◽  
Hyphal Growth ◽  
Mitogen Activated Protein Kinase ◽  
Phenotypic Characterization ◽  
Cell Wall Biosynthesis ◽  
Appressorium Formation

The mitogen-activated protein kinase MoOsm1–mediated osmoregulation pathway plays crucial roles in stress responses, asexual and sexual development, and pathogenicity in Magnaporthe oryzae. Utilizing an affinity purification approach, we identified the putative transcriptional activator MoMsn2 as a protein that interacts with MoOsm1 in vivo. Disruption of the MoMSN2 gene resulted in defects in aerial hyphal growth, conidial production, and infection of host plants. Quantitative reverse transcription-polymerase chain reaction analysis showed that the expression of several genes involved in conidiophore formation was reduced in ΔMomsn2, suggesting that MoMsn2 might function as a transcriptional regulator of these genes. Subsequently, MoCos1 was identified as one of the MoMsn2 targets through yeast one-hybrid analysis in which MoMsn2 binds to the AGGGG and CCCCT motif of the MoCOS1 promoter region. Phenotypic characterization showed that MoMsn2 was required for appressorium formation and penetration and pathogenicity. Although the ΔMomsn2 mutant was tolerant to the cell-wall stressor Calcofluor white, it was sensitive to common osmotic stressors. Further analysis suggests that MoMsn2 is involved in the regulation of the cell-wall biosynthesis pathway. Finally, transcriptome data revealed that MoMsn2 modulates numerous genes participating in conidiation, infection, cell-wall integrity, and stress response. Collectively, our results led to a model in which MoMsn2 mediates a series of downstream genes that control aerial hyphal growth, conidiogenesis, appressorium formation, cell-wall biosynthesis, and infection and that also offer potential targets for the development of new disease management strategies.

scholarly journals TmkA, a Mitogen-Activated Protein Kinase of Trichoderma virens, Is Involved in Biocontrol Properties and Repression of Conidiation in the Dark

2003 ◽  
Vol 2 (3) ◽  
pp. 446-455 ◽  
Author(s):  
Prasun K. Mukherjee ◽  
Jagannathan Latha ◽  
Ruthi Hadar ◽  
Benjamin A. Horwitz
Keyword(s):  
Protein Kinase ◽  
Plant Pathogens ◽  
Sclerotium Rolfsii ◽  
Pathogenic Fungi ◽  
Mitogen Activated Protein Kinase ◽  
Trichoderma Virens ◽  
Loss Of Function ◽  
Wild Type ◽  
Mapk Cascades ◽  
Mitogen Activated Protein

ABSTRACT Trichoderma virens is a mycoparasitic fungus used in biocontrol of soilborne plant pathogens. It inhibits or kills plant-pathogenic fungi through production of antifungal antibiotics and parasitism of hyphae and sclerotia. Conidiation, or the production of asexual spores, an inducible process triggered by light or nutrient stress, is an important trait in survival and also development of formulation products. In many fungi, signaling pathways, including mitogen-activated protein kinase (MAPK) cascades, have been implicated in parasitism of host plants as well as in the production of asexual spores. Here, we have studied the role of a MAPK gene, that for TmkA, in conidiation and antagonistic properties of a biocontrol strain of T. virens. Through single- and double-crossover recombination, we obtained three tmkA loss-of-function mutants. The TmkA transcript was not detectable in these mutants. The mutants conidiated in the dark, although photoinduction was normal and the light sensitivities of the wild type and the mutant were the same. The mutants had, overall, normal colony morphology, but their radial growth rate was reduced by about 16%, with no decrease in biomass production. Against Rhizoctonia solani hyphae, the knockout mutants exhibited mycoparasitic coiling and lysis of host hyphae similar to that of the wild type. The mutants, however, were less effective in colonizing the sclerotia of R. solani. On Sclerotium rolfsii, the MAPK loss-of-function mutants had reduced antagonistic properties in confrontation assays and failed to parasitize the sclerotia. TmkA-dependent and -independent pathways are thus involved in antagonism against different hosts. Finally, in contrast to the case for other filamentous fungi studied so far, signaling through a MAPK represses, rather than induces, asexual sporulation.

scholarly journals A Novel Nitrogen and Carbon Metabolism Regulatory Cascade Is Implicated in Entomopathogenicity of the Fungus Metarhizium robertsii

mSystems ◽  
2021 ◽  
Author(s):  
Yamin Meng ◽  
Xing Zhang ◽  
Dan Tang ◽  
Xiaoxuan Chen ◽  
Dan Zhang ◽  
...  
Keyword(s):  
Carbon Metabolism ◽  
Hyphal Growth ◽  
Pathogenic Fungi ◽  
Mitogen Activated Protein Kinase ◽  
Physical Barrier ◽  
Metarhizium Robertsii ◽  
Content Type ◽  
Regulatory Cascade ◽  
Mitogen Activated Protein ◽  
Nutrient Selection

Penetration of the cuticle, the first physical barrier to pathogenic fungi, is the prerequisite for fungal infection of insects. In the entomopathogenic fungus Metarhizium robertsii , we found that the Fus3–mitogen-activated protein kinase (MAPK) and the transcription factor regulator of nutrient selection 1 (RNS1) constitute a novel cascade that controls cuticle penetration by regulating degradation of cuticular lipids, proteins, and chitin to obtain nutrients for hyphal growth and entry into the insect hemocoel.

scholarly journals NADPH Oxidase ClNOX2 Regulates Melanin-Mediated Development and Virulence in Curvularia lunata

2020 ◽  
Vol 33 (11) ◽  
pp. 1315-1329
Author(s):  
Fen Wang ◽  
Weida Gao ◽  
Jiaying Sun ◽  
Xiuwen Mao ◽  
Kexin Liu ◽  
...  
Keyword(s):  
Cell Wall ◽  
Signaling Pathway ◽  
Hyphal Growth ◽  
Conidial Germination ◽  
Mitogen Activated Protein Kinase ◽  
Ros Generation ◽  
Deletion Mutants ◽  
Curvularia Lunata ◽  
Kinase Gene ◽  
Melanin Biosynthesis

The role of NADPH oxidases (NOXs) in pathogenesis and development in the Curvularia leaf spot agent Curvularia lunata remains poorly understood. In this study, we identified C. lunata ClNOX2, which localized to the plasma membrane and was responsible for reactive oxygen species (ROS) generation. Scavenging the ROS production inhibited the conidial germination and appressorial formation. The ClNOX2 and ClBRN1 deletion mutants were defective in 1,8-dihydroxynaphthalene (DHN) melanin accumulation, appressorial formation, and cellulase synthesis and exhibited lower virulence. However, disruption of the ClNOX2 and ClBRN1 genes facilitated hyphal growth, enhanced stress adaptation to cell-wall-disrupting agents, and promoted developmental processes such as conidiation, conidial germination, and pseudothecium and ascus formation. Interestingly, loss of ClM1, the cell wall integrity (CWI) mitogen-activated protein kinase gene in C. lunata, led to morphology and pathogenicity phenotypes similar to ClNOX2 and ClBRN1 deletion mutants such as abnormal conidia, fewer appressoria, less melanin, increased hyphal growth, and enhanced tolerance to Congo red (CR). These results indicated that the ClNOX2 gene plays an important role in C. lunata development and virulence via regulating intracellular DHN melanin biosynthesis. Quantitative reverse-transcription PCR revealed that the ClNOX2-related ROS signaling pathway and ClM1-mediated CWI signaling pathway are cross-linked in regulating DHN melanin biosynthesis. Our findings provide new insights into how ClNOX2 participates in pathogenesis and development in hemibiotrophic plant fungal pathogens. [Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

scholarly journals Differential Role of Threonine and Tyrosine Phosphorylation in the Activation and Activity of the Yeast MAPK Slt2

2021 ◽  
Vol 22 (3) ◽  
pp. 1110
Author(s):  
Gema González-Rubio ◽  
Ángela Sellers-Moya ◽  
Humberto Martín ◽  
María Molina
Keyword(s):  
Cell Wall ◽  
Biological Activity ◽  
Biological Significance ◽  
Mitogen Activated Protein Kinase ◽  
Activation Loop ◽  
High Increase ◽  
Dual Specificity ◽  
Mitogen Activated Protein ◽  
Full Activation

The Mitogen-Activated Protein Kinase (MAPK) Slt2 is central to signaling through the yeast Cell Wall Integrity (CWI) pathway. MAPKs are regulated by phosphorylation at both the threonine and tyrosine of the conserved TXY motif within the activation loop (T190/Y192 in Slt2). Since phosphorylation at both sites results in the full activation of MAPKs, signaling through MAPK pathways is monitored with antibodies that detect dually phosphorylated forms. However, most of these antibodies also recognize monophosphorylated species, whose relative abundance and functionality are diverse. By using different phosphospecific antibodies and phosphate-affinity (Phos-tag) analysis on distinct Slt2 mutants, we determined that Y192- and T190-monophosphorylated species coexist with biphosphorylated Slt2, although most of the Slt2 pool remains unphosphorylated following stress. Among the monophosphorylated forms, only T190 exhibited biological activity. Upon stimulation, Slt2 is first phosphorylated at Y192, mainly by the MAPKK Mkk1, and this phosphorylation is important for the subsequent T190 phosphorylation. Similarly, dephosphorylation of Slt2 by the Dual Specificity Phosphatase (DSP) Msg5 is ordered, with dephosphorylation of T190 depending on previous Y192 dephosphorylation. Whereas Y192 phosphorylation enhances the Slt2 catalytic activity, T190 is essential for this activity. The conserved T195 residue is also critical for Slt2 functionality. Mutations that abolish the activity of Slt2 result in a high increase in inactive Y192-monophosphorylated Slt2. The coexistence of different Slt2 phosphoforms with diverse biological significance highlights the importance of the precise detection of the Slt2 phosphorylation status.

scholarly journals Exercise-induced mitogen-activated protein kinase signalling in skeletal muscle

2004 ◽  
Vol 63 (2) ◽  
pp. 227-232 ◽  
Author(s):  
Yun Chau Long ◽  
Ulrika Widegren ◽  
Juleen R. Zierath
Keyword(s):  
Skeletal Muscle ◽  
Protein Kinase ◽  
Muscle Contraction ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Cascades ◽  
Extracellular Signal ◽  
Mapk Signalling ◽  
Mitogen Activated Protein ◽  
Exercise Induced ◽  
Response To Exercise

Exercise training improves glucose homeostasis through enhanced insulin sensitivity in skeletal muscle. Muscle contraction through physical exercise is a physiological stimulus that elicits multiple biochemical and biophysical responses and therefore requires an appropriate control network. Mitogen-activated protein kinase (MAPK) signalling pathways constitute a network of phosphorylation cascades that link cellular stress to changes in transcriptional activity. MAPK cascades are divided into four major subfamilies, including extracellular signal-regulated kinases 1 and 2, p38 MAPK, c-Jun NH2-terminal kinase and extracellular signal-regulated kinase 5. The present review will present the current understanding of parallel MAPK signalling in human skeletal muscle in response to exercise and muscle contraction, with an emphasis on identifying potential signalling mechanisms responsible for changes in gene expression.

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