Mitogen-Activated Protein Kinase hog1 in the Entomopathogenic Fungus Beauveria bassiana Regulates Environmental Stress Responses and Virulence to Insects

ABSTRACT Beauveria bassiana is an economically important insect-pathogenic fungus which is widely used as a biocontrol agent to control a variety of insect pests. However, its insecticide efficacy in the field is often influenced by adverse environmental factors. Thus, understanding the genetic regulatory processes involved in the response to environmental stress would facilitate engineering and production of a more efficient biocontrol agent. Here, a mitogen-activated protein kinase (MAPK)-encoding gene, Bbhog1, was isolated from B. bassiana and shown to encode a functional homolog of yeast HIGH-OSMOLARITY GLYCEROL 1 (HOG1). A Bbhog1 null mutation was generated in B. bassiana by targeted gene replacement, and the resulting mutants were more sensitive to hyperosmotic stress, high temperature, and oxidative stress than the wild-type controls. These results demonstrate the conserved function of HOG1 MAPKs in the regulation of abiotic stress responses. Interestingly, ΔBbhog1 mutants exhibited greatly reduced pathogenicity, most likely due to a decrease in spore viability, a reduced ability to attach to insect cuticle, and a reduction in appressorium formation. The transcript levels of two hydrophobin-encoding genes, hyd1 and hyd2, were dramatically decreased in a ΔBbhog1 mutant, suggesting that Bbhog1 may regulate the expression of the gene associated with hydrophobicity or adherence.

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Plant Mitogen-Activated Protein Kinase Cascades in Environmental Stresses

International Journal of Molecular Sciences ◽

10.3390/ijms22041543 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1543

Author(s):

Li Lin ◽

Jian Wu ◽

Mingyi Jiang ◽

Youping Wang

Keyword(s):

Protein Kinase ◽

Environmental Stress ◽

Stress Responses ◽

Extreme Temperature ◽

Environmental Stresses ◽

Mitogen Activated Protein Kinase ◽

Hormone Production ◽

Mapk Cascades ◽

Stress Signal ◽

Mitogen Activated Protein

Due to global warming and population growth, plants need to rescue themselves, especially in unfavorable environments, to fulfill food requirements because they are sessile organisms. Stress signal sensing is a crucial step that determines the appropriate response which, ultimately, determines the survival of plants. As important signaling modules in eukaryotes, plant mitogen-activated protein kinase (MAPK) cascades play a key role in regulating responses to the following four major environmental stresses: high salinity, drought, extreme temperature and insect and pathogen infections. MAPK cascades are involved in responses to these environmental stresses by regulating the expression of related genes, plant hormone production and crosstalk with other environmental stresses. In this review, we describe recent major studies investigating MAPK-mediated environmental stress responses. We also highlight the diverse function of MAPK cascades in environmental stress. These findings help us understand the regulatory network of MAPKs under environmental stress and provide another strategy to improve stress resistance in crops to ensure food security.

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Mitogen-Activated Protein Kinase Expression Profiling Revealed Its Role in Regulating Stress Responses in Potato (Solanum tuberosum)

Plants ◽

10.3390/plants10071371 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1371

Author(s):

Madiha Zaynab ◽

Athar Hussain ◽

Yasir Sharif ◽

Mahpara Fatima ◽

Mateen Sajid ◽

...

Keyword(s):

Solanum Tuberosum ◽

Protein Kinase ◽

Stress Responses ◽

Expression Profiling ◽

Regulatory Elements ◽

Mitogen Activated Protein Kinase ◽

High Expression ◽

Primary Data ◽

A Genome ◽

Mitogen Activated Protein

Mitogen-activated protein kinase (MAPK) cascades are the universal signal transduction networks that regulate cell growth and development, hormone signaling, and other environmental stresses. However, their essential contribution to plant tolerance is very little known in the potato (Solanum tuberosum) plant. The current study carried out a genome-wide study of StMAPK and provided a deep insight using bioinformatics tools. In addition, the relative expression of StMAPKs was also assessed in different plant tissues. The similarity search results identified a total of 22 StMAPK genes in the potato genome. The sequence alignment also showed conserved motif TEY/TDY in most StMAPKs with conserved docking LHDXXEP sites. The phylogenetic analysis divided all 22 StMAPK genes into five groups, i.e., A, B, C, D, and E, showing some common structural motifs. In addition, most of the StMAPKs were found in a cluster form at the terminal of chromosomes. The promoter analysis predicted several stress-responsive Cis-acting regulatory elements in StMAPK genes. Gene duplication under selection pressure also indicated several purifying and positive selections in StMAPK genes. In potato, StMAPK2, StMAPK6, and StMAPK19 showed a high expression in response to heat stress. Under ABA and IAA treatment, the expression of the total 20 StMAPK genes revealed that ABA and IAA played an essential role in this defense process. The expression profiling and real-time qPCR (RT-qPCR) exhibited their high expression in roots and stems compared to leaves. These results deliver primary data for functional analysis and provide reference data for other important crops.

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Cell Cycle Arrest and Reversion of Ras-Induced Transformation by a Conditionally Activated Form of Mitogen-Activated Protein Kinase Kinase Kinase 3

Molecular and Cellular Biology ◽

10.1128/mcb.19.5.3857 ◽

1999 ◽

Vol 19 (5) ◽

pp. 3857-3868 ◽

Cited By ~ 57

Author(s):

Heidrun Ellinger-Ziegelbauer ◽

Kathleen Kelly ◽

Ulrich Siebenlist

Keyword(s):

Cell Cycle ◽

Protein Kinase ◽

Cyclin D1 ◽

Stress Responses ◽

Cell Cycle Progression ◽

Cellular Transformation ◽

Mitogen Activated Protein Kinase ◽

Cycle Progression ◽

Mapk Kinase ◽

Mitogen Activated Protein

ABSTRACT Signal-induced proliferation, differentiation, or stress responses of cells depend on mitogen-activated protein kinase (MAPK) cascades, the core modules of which consist of members of three successively acting kinase families (MAPK kinase kinase [MAP3K], MAPK kinase, and MAPK). It is demonstrated here that the MEKK3 kinase inhibits cell proliferation, a biologic response not commonly associated with members of the MAP3K family of kinases. A conditionally activated form of MEKK3 stably expressed in fibroblasts arrests these cells in early G1. MEKK3 critically blocks mitogen-driven expression of cyclin D1, a cyclin which is essential for progression of fibroblasts through G1. The MEKK3-induced block of cyclin D1 expression and of cell cycle progression may be mediated via p38 MAPK, a downstream effector of MEKK3. The MEKK3-mediated block of proliferation also reverses Ras-induced cellular transformation, suggesting possible tumor-suppressing functions for this kinase. Together, these results suggest an involvement of the MEKK3 kinase in negative regulation of cell cycle progression, and they provide the first insights into biologic activities of this kinase.

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Stress-Activated Protein Kinase Pathway Functions To Support Protein Synthesis and Translational Adaptation in Response to Environmental Stress in Fission Yeast

Eukaryotic Cell ◽

10.1128/ec.4.11.1785-1793.2005 ◽

2005 ◽

Vol 4 (11) ◽

pp. 1785-1793 ◽

Cited By ~ 39

Author(s):

Isabelle Dunand-Sauthier ◽

Carol A. Walker ◽

Jana Narasimhan ◽

Amanda K. Pearce ◽

Ronald C. Wek ◽

...

Keyword(s):

Protein Synthesis ◽

Protein Kinase ◽

Osmotic Stress ◽

Environmental Stress ◽

Fission Yeast ◽

Translation Initiation ◽

Mitogen Activated Protein Kinase ◽

Wild Type ◽

Eif2α Phosphorylation ◽

Mitogen Activated Protein

ABSTRACT The stress-activated protein kinase (SAPK) pathway plays a central role in coordinating gene expression in response to diverse environmental stress stimuli. We examined the role of this pathway in the translational response to stress in Schizosaccharomyces pombe. Exposing wild-type cells to osmotic stress (KCl) resulted in a rapid but transient reduction in protein synthesis. Protein synthesis was further reduced in mutants disrupting the SAPK pathway, including the mitogen-activated protein kinase Wis1 or the mitogen-activated protein kinase Spc1/Sty1, suggesting a role for these stress response factors in this translational control. Further polysome analyses revealed a role for Spc1 in supporting translation initiation during osmotic stress, and additionally in facilitating translational adaptation. Exposure to oxidative stress (H2O2) resulted in a striking reduction in translation initiation in wild-type cells, which was further reduced in spc1 − cells. Reduced translation initiation correlated with phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α) in wild-type cells. Disruption of Wis1 or Spc1 kinase or the downstream bZip transcription factors Atf1 and Pap1 resulted in a marked increase in eIF2α phosphorylation which was dependent on the eIF2α kinases Hri2 and Gcn2. These findings suggest a role for the SAPK pathway in supporting translation initiation and facilitating adaptation to environmental stress in part through reducing eIF2α phosphorylation in fission yeast.

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Characterization of a mitogen-activated protein kinase fromPneumocystis carinii

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1998.275.1.l193 ◽

1998 ◽

Vol 275 (1) ◽

pp. L193-L199 ◽

Cited By ~ 5

Author(s):

Charles F. Thomas ◽

Theodore J. Kottom ◽

Edward B. Leof ◽

Andrew H. Limper

Keyword(s):

Signal Transduction ◽

Protein Kinase ◽

Cell Biology ◽

Pathogenic Fungus ◽

Pneumocystis Carinii ◽

Severe Pneumonia ◽

Mitotic Cell ◽

Mitogen Activated Protein Kinase ◽

Signal Transduction Cascade ◽

Mitogen Activated Protein

The pathogenic fungus Pneumocystis carinii causes severe pneumonia in patients with impaired immunity, particularly patients with acquired immunodeficiency syndrome. The life cycle of P. carinii is poorly understood, and the inability to continuously culture P. carinii is a major limitation in understanding its cell biology. In fungi homologous to P. carinii, pheromone mating factors signal through a mitogen-activated protein kinase (MAPK) signal transduction cascade, resulting in mitotic cell cycle arrest and entry into a pathway of conjugation, cellular differentiation, and proliferation. Using degenerate PCR and library screening, we have identified a MAPK cDNA in P. carinii that is highly homologous to fungal MAPKs involved in the pheromone mating signal transduction cascade, and we demonstrate MAPK activity in P. carinii lysates with a specific antiserum derived from the translated P. carinii MAPK cDNA sequence.

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The rice germin-like protein OsGLP1 participates in acclimation to UV-B radiation

Plant Physiology ◽

10.1093/plphys/kiab125 ◽

2021 ◽

Author(s):

Zhi-dan He ◽

Mi-lin Tao ◽

David W M Leung ◽

Xiao-yu Yan ◽

Long Chen ◽

...

Keyword(s):

Protein Kinase ◽

White Light ◽

Stress Responses ◽

Ultraviolet B ◽

Mitogen Activated Protein Kinase ◽

Leaf Angle ◽

Resistance Locus ◽

Expression Levels ◽

Natural Sunlight ◽

Mitogen Activated Protein

Abstract Exposure to ultraviolet B radiation (UV-B) stress can have serious effects on the growth and development of plants. Germin-like proteins (GLPs) may be involved in different abiotic and biotic stress responses in different plants, but little is known about the role of GLPs in UV-B stress response and acclimation in plants. In the present study, knockout of germin-like protein 8-14 (OsGLP1) using the CRISPR/Cas9 system resulted in mutant rice (Oryza sativa L.) plants (herein called glp1) that exhibited UV-B-dependent formation of lesion mimic in leaves. Moreover, glp1 grown under solar radiation (including UV-B) showed decreased plant height and increased leaf angle, but we observed no significant differences in phenotypes between wild-type (WT) plants and glp1 grown under artificial light lacking UV-B. Fv/Fm, Y (II) and the expression of many genes, based on RNA-seq analysis, related to photosynthesis were also only reduced in glp1, but not in WT, after transfer from a growth cabinet illuminated with artificial white light lacking UV-B to growth under natural sunlight. The genes-associated with flavonoid metabolism as well as UV RESISTANCE LOCUS 8 (OsUVR8), PHYTOCHROME INTERACTING FACTOR-LIKE 15-like (OsPIF3), pyridoxal 5'-phosphate synthase subunit PDX1.2 (OsPDX1.2), deoxyribodipyrimidine photolyase (OsPHR) and deoxyribodipyrimidine photolyase family protein-like (OsPHRL) exhibited lower expression levels, while higher expression levels of mitogen-activated protein kinase 5-like (OsMPK3), mitogen-activated protein kinase 13-like (OsMPK13) and transcription factor MYB4-like (OsMYB4) were observed in glp1 than in WT after transfer from a growth cabinet illuminated with artificial white light to growth under natural sunlight. Therefore, mutations in OsGLP1 resulted in rice plants more sensitive to UV-B and reduced expression of some genes for UV-B protection, suggesting that OsGLP1 is involved in acclimation to UV-B radiation.

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Identification and Characterization of 12 Mitogen-activated Protein Kinase Genes Implicated in Stress Responses in Cherry Rootstocks

Journal of the American Society for Horticultural Science ◽

10.21273/jashs03816-16 ◽

2016 ◽

Vol 141 (5) ◽

pp. 490-497 ◽

Cited By ~ 1

Author(s):

Xiaojuan Zong ◽

Jiawei Wang ◽

Li Xu ◽

Hairong Wei ◽

Xin Chen ◽

...

Keyword(s):

Protein Kinase ◽

Stress Responses ◽

Prunus Avium ◽

Expression Profiles ◽

Mitogen Activated Protein Kinase ◽

Biotic Stresses ◽

Mitogen Activated Protein ◽

Genetic Transformation System ◽

Cherry Rootstocks ◽

Gisela 6

Improving the poor resistance to environmental stress and the weak development of roots system in the cherry (Prunus) rootstock ‘Gisela 6’ (Prunus cerasus × Prunus canescens) is of great importance for sustainable sweet cherry (Prunus avium) production. Although a stable genetic transformation system has been developed for ‘Gisela 6’ rootstock, there is little information on the identification of genes involved in stress resistance. Using the cherry rootstock cultivar Gisela 6, we identified a total of 12 novel mitogen-activated protein kinase (MAPK) genes, designated PcMPKs. Phylogenetic analysis revealed that the PcMPKs could be divided into four groups, designated A, B, C, and D. In addition, an intron–exon structure analysis for the PcMPKs was conducted to help further understand the structure–function relationships within the cherry family. The expression profiles of PcMPKs in response to abiotic and biotic stresses were characterized using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Five PcMPKs (i.e., PcMPK4-1, PcMPK4-2, PcMPK3, PcMPK6, and PcMPK18) exhibited differential expression, and suggested their potential roles in plant responding to various stresses. This study provides the basis for further analysis on the physiological functions of PcMPKs in environmental tolerance in cherry rootstocks.

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Identification of a novel mitogen-activated protein kinase kinase gene (MKK2) in the oilseed rape Brassica campestris

Biologia ◽

10.2478/s11756-014-0455-8 ◽

2014 ◽

Vol 69 (11) ◽

Author(s):

Teng Zhang ◽

Yuan Wang ◽

Juan Wang ◽

Xiao Xia ◽

Ning Yang ◽

...

Keyword(s):

Protein Kinase ◽

Stress Responses ◽

Brassica Campestris ◽

Plant Stress ◽

Mitogen Activated Protein Kinase ◽

Biotic And Abiotic Stress ◽

Kinase Gene ◽

Isolation And Characterization ◽

Mapk Cascades ◽

Mitogen Activated Protein

AbstractMitogen-activated protein kinase (MAPK) cascades participate in various processes, including plant growth and development as well as biotic and abiotic stress responses. MAPK kinases (MKKs), which link MPKs and MPKK kinases, are involved in MAPK cascades by mediating various plant stress responses. However, only a few MKKs from Brassica campestris (rape) have been functionally characterized. This study delivers the results from isolation and characterization of a novel gene, MKK2, from rape. Bioinformatics analysis revealed that the cDNA length of MKK2 is 1,344 bp with an open reading frame of 1,068 bp, which encodes a polypeptide containing 355 amino acids. The obtained MKK2 exhibited a predicted molecular mass of 39.3 kDa and an isoelectric point of 6.8. Quantitative real-time polymerase chain reaction analysis revealed that MKK2 expression can be induced by cold and salt. Western blot analysis revealed that MKK2 protein expression can be induced by cold, salt, and UV-B radiation. The MKK2 protein was localized in the nucleus. These results suggest that MKK2 is important for the regulation of cold- and salt-stress responses in plants.

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3pK, a novel mitogen-activated protein (MAP) kinase-activated protein kinase, is targeted by three MAP kinase pathways.

Molecular and Cellular Biology ◽

10.1128/mcb.16.12.6687 ◽

1996 ◽

Vol 16 (12) ◽

pp. 6687-6697 ◽

Cited By ~ 128

Author(s):

S Ludwig ◽

K Engel ◽

A Hoffmeyer ◽

G Sithanandam ◽

B Neufeld ◽

...

Keyword(s):

Protein Kinase ◽

Map Kinase ◽

Stress Responses ◽

Specific Inhibitor ◽

Mitogen Activated Protein Kinase ◽

Mapk Cascades ◽

Mitogen Activated Protein ◽

Stimulation Of

Recently we have identified a mitogen-activated protein kinase (MAPK)-activated protein kinase, named 3pK (G. Sithanandam, F. Latif, U. Smola, R. A. Bernal, F.-M. Duh, H. Li, I. Kuzmin, V. Wixler, L. Geil, S. Shresta, P. A. Lloyd, S. Bader, Y. Sekido, K. D. Tartof, V. I. Kashuba, E. R. Zabarovsky, M. Dean, G. Klein, B. Zbar, M. I. Lerman, J. D. Minna, U. R. Rapp, and A. Allikmets, Mol. Cell. Biol. 16:868-876, 1996). In vitro characterization of the kinase revealed that 3pK is activated by ERK. It was further shown that 3pK is phosphorylated in vivo after stimulation of cells with serum. However, the in vivo relevance of this observation in terms of involvement of the Raf/MEK/ERK cascade has not been established. Here we show that 3pK is activated in vivo by the growth inducers serum and tetradecanoyl phorbol acetate in promyelocytic HL60 cells and transiently transfected embryonic kidney 293 cells. Activation of 3pK was Raf dependent and was mediated by the Raf/MEK/ERK kinase cascade. 3pK was also shown to be activated after stress stimulation of cells. In vitro studies with recombinant proteins demonstrate that in addition to ERK, members of other subgroups of the MAPK family, namely, p38RK and Jun-N-terminal kinases/stress-activated protein kinases, were also able to phosphorylate and activate 3pK. Cotransfection experiments as well as the use of a specific inhibitor of p38RK showed that these in vitro upstream activators also function in vivo, identifying 3pK as the first kinase to be activated through all three MAPK cascades. Thus, 3pK is a novel convergence point of different MAPK pathways and could function as an integrative element of signaling in both mitogen and stress responses.

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