47 results on '"Colcombet, Jean"'
Search Results
2. The MKK3 MAPK cascade integrates temperature and after-ripening signals to modulate seed germination.
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Masahiko Otani, Ryo Tojo, Regnard, Sarah, Lipeng Zheng, Takumi Hoshi, Suzuha Ohmori, Natsuki Tachibana, Tomohiro Sano, Shizuka Koshimizu, Kazuya Ichimura, Colcombet, Jean, and Naoto Kawakami
- Subjects
GERMINATION ,SEED quality ,LOCUS (Genetics) ,MITOGEN-activated protein kinases ,GENE expression ,ABSCISIC acid - Abstract
The timing of seed germination is controlled by the combination of internal dormancy and external factors. Temperature is a major environmental factor for seed germination. The permissive temperature range for germination is narrow in dormant seeds and expands during after-ripening (AR) (dormancy release). Quantitative trait loci analyses of preharvest sprouting in cereals have revealed that MKK3, a mitogen-activated protein kinase (MAPK) cascade protein, is a negative regulator of grain dormancy. Here, we show that the MAPKKK19/20-MKK3-MPK1/2/7/14 cascade modulates the germination temperature range in Arabidopsis seeds by elevating the germinability of the seeds at sub-and supraoptimal temperatures. The expression of MAPKKK19 and MAPKKK20 is induced around optimal temperature for germination in after-ripened seeds but repressed in dormant seeds. MPK7 activation depends on the expression levels of MAPKKK19/20, with expression occurring under conditions permissive for germination. Abscisic acid (ABA) and gibberellin (GA) are two major phytohormones which are involved in germination control. Activation of the MKK3 cascade represses ABA biosynthesis enzyme gene expression and induces expression of ABA catabolic enzyme and GA biosynthesis enzyme genes, resulting in expansion of the germinable temperature range. Our data demonstrate that the MKK3 cascade integrates temperature and AR signals to phytohormone metabolism and seed germination. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Integrated multi‐omics and genetic analyses reveal molecular determinants underlying Arabidopsis snap33 mutant phenotype.
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Henchiri, Houda, Rayapuram, Naganand, Alhoraibi, Hanna M., Caïus, José, Paysant‐Le Roux, Christine, Citerne, Sylvie, Hirt, Heribert, Colcombet, Jean, Sturbois, Bénédicte, and Bigeard, Jean
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MULTIOMICS ,PHENOTYPES ,ARABIDOPSIS ,MESSENGER RNA ,SALICYLIC acid ,PROTEIN receptors - Abstract
SUMMARY: The secretory pathway is essential for plant immunity, delivering diverse antimicrobial molecules into the extracellular space. Arabidopsis thaliana soluble N‐ethylmaleimide‐sensitive‐factor attachment protein receptor SNAP33 is a key actor of this process. The snap33 mutant displays dwarfism and necrotic lesions, however the molecular determinants of its macroscopic phenotypes remain elusive. Here, we isolated several new snap33 mutants that exhibited constitutive cell death and H2O2 accumulation, further defining snap33 as an autoimmune mutant. We then carried out quantitative transcriptomic and proteomic analyses showing that numerous defense transcripts and proteins were up‐regulated in the snap33 mutant, among which genes/proteins involved in defense hormone, pattern‐triggered immunity, and nucleotide‐binding domain leucine‐rich‐repeat receptor signaling. qRT‐PCR analyses and hormone dosages supported these results. Furthermore, genetic analyses elucidated the diverse contributions of the main defense hormones and some nucleotide‐binding domain leucine‐rich‐repeat receptor signaling actors in the establishment of the snap33 phenotype, emphasizing the preponderant role of salicylic acid over other defense phytohormones. Moreover, the accumulation of pattern‐triggered immunity and nucleotide‐binding domain leucine‐rich‐repeat receptor signaling proteins in the snap33 mutant was confirmed by immunoblotting analyses and further shown to be salicylic acid‐dependent. Collectively, this study unveiled molecular determinants underlying the Arabidopsis snap33 mutant phenotype and brought new insights into autoimmunity signaling. Significance Statement: SNAP33 is a key actor of secretion and the snap33 mutant exhibits dwarfism and necrotic lesions. The snap33 mutant is here further defined as an autoimmune mutant and molecular determinants of its macroscopic phenotypes are unveiled. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Arabidopsis SOMATIC EMBRYOGENESIS RECEPTOR KINASES1 and 2 Are Essential for Tapetum Development and Microspore Maturation
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Colcombet, Jean, Boisson-Dernier, Aurélien, Ros-Palau, Roc, Vera, Carlos E., and Schroeder, Julian I.
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- 2005
5. Constitutively Active Arabidopsis MAP Kinase 3 Triggers Defense Responses Involving Salicylic Acid and SUMM2 Resistance Protein
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Genot, Baptiste, Lang, Julien, Berriri, Souha, Garmier, Marie, Gilard, Françoise, Pateyron, Stéphanie, Haustraete, Katrien, Van Der Streaten, Dominique, Hirt, Heribert, and Colcombet, Jean
- Published
- 2017
6. Sulfate Is Both a Substrate and an Activator of the Voltage-Dependent Anion Channel of Arabidopsis Hypocotyl Cells
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Frachisse, Jean-Marie, Thomine, Sébastien, Colcombet, Jean, Guern, Jean, and Barbier-Brygoo, Hélène
- Published
- 1999
7. The role of ABA and MAPK signaling pathways in plant abiotic stress responses
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Danquah, Agyemang, de Zelicourt, Axel, Colcombet, Jean, and Hirt, Heribert
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- 2014
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8. Constitutively Active Mitogen-Activated Protein Kinase Versions Reveal Functions of Arabidopsis MPK4 in Pathogen Defense Signaling
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Berriri, Souha, Garcia, Ana Victoria, dit Frey, Nicolas Frei, Rozhon, Wilfried, Pateyron, Stéphanie, Leonhardt, Nathalie, Montillet, Jean-Luc, Leung, Jeffrey, Hirt, Heribert, and Colcombet, Jean
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- 2012
9. The MAP Kinase MPK4 Is Required for Cytokinesis in Arabidopsis thaliana
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Kosetsu, Ken, Matsunaga, Sachihiro, Nakagami, Hirofumi, Colcombet, Jean, Sasabe, Michiko, Soyano, Takashi, Takahashi, Yuji, Hirt, Heribert, and Machida, Yasunori
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- 2010
10. Distinct pH regulation of slow and rapid anion channels at the plasma membrane of Arabidopsis thaliana hypocotyl cells
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Colcombet, Jean, Lelièvre, Françoise, Thomine, Sébastien, Barbier-Brygoo, Hélène, and Frachisse, Jean-Marie
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- 2005
11. Identification and characterization of an ABA-activated MAP kinase cascade in Arabidopsis thaliana
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Danquah, Agyemang, de Zélicourt, Axel, Boudsocq, Marie, Neubauer, Jorinde, dit Frey, Nicolas Frei, Leonhardt, Nathalie, Pateyron, Stephanie, Gwinner, Frederik, Tamby, Jean-Philippe, Ortiz-Masia, Dolores, Marcote, Maria J., Hirt, Heribert, and Colcombet, Jean
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- 2015
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12. MPK3 and MPK6 control salicylic acid signaling by up-regulating NLR receptors during pattern- and effector-triggered immunity.
- Author
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Lang, Julien, Genot, Baptiste, Bigeard, Jean, and Colcombet, Jean
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SALICYLIC acid ,ARABIDOPSIS proteins ,MITOGEN-activated protein kinases ,IMMUNITY ,DISEASE resistance of plants - Abstract
Arabidopsis thaliana mitogen-activated protein kinases 3 and 6 (MPK3/6) are activated transiently during pathogen-associated molecular pattern-triggered immunity (PTI) and durably during effector-triggered immunity (ETI). The functional differences between these two kinds of activation kinetics and how they coordinate the two layers of plant immunity remain poorly understood. Here, by suppressor analyses, we demonstrate that ETI-mediating nucleotide-binding domain leucine-rich repeat receptors (NLRs) and the NLR signaling components NDR1 and EDS1 can promote the salicylic acid sector of defense downstream of MPK3 activity. Moreover, we provide evidence that both sustained and transient MPK3/6 activities positively control the expression of several NLR genes, including AT3G04220 and AT4G11170. We further show that NDR1 and EDS1 contribute to the up-regulation of these two NLRs in both an ETI and a PTI context. Remarkably, whereas in ETI MPK3/6 activities are dependent on NDR1 and EDS1, they are not in PTI, suggesting crucial differences in the two signaling pathways. Finally, we demonstrate that expression of the NLR AT3G04220 is sufficient to induce expression of defense genes from the salicylic acid branch. Overall, this study expands our knowledge of MPK3/6 functions during immunity and provides new insights into the intricate interplay of PTI and ETI. [ABSTRACT FROM AUTHOR]
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- 2022
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13. The Lys‐motif receptor LYK4 mediates Enterobacter sp. SA187 triggered salt tolerance in Arabidopsis thaliana.
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Rolli, Eleonora, de Zélicourt, Axel, Alzubaidy, Hanin, Karampelias, Michael, Parween, Sabiha, Rayapuram, Naganand, Han, Baoda, Froehlich, Katja, Abulfaraj, Aala A., Alhoraibi, Hanna, Mariappan, Kiruthiga, Andrés‐Barrao, Cristina, Colcombet, Jean, and Hirt, Heribert
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ENTEROBACTER ,PLANT-microbe relationships ,DISEASE resistance of plants ,SALT ,ROOT growth - Abstract
Summary: Root endophytes establish beneficial interactions with plants, improving holobiont resilience and fitness, but how plant immunity accommodates beneficial microbes is poorly understood. The multi‐stress tolerance‐inducing endophyte Enterobacter sp. SA187 triggers a canonical immune response in Arabidopsis only at high bacterial dosage (>108 CFUs ml−1), suggesting that SA187 is able to evade or suppress the plant defence system at lower titres. Although SA187 flagellin epitopes are recognized by the FLS2 receptor, SA187‐triggered salt tolerance functions independently of the FLS2 system. In contrast, overexpression of the chitin receptor components LYK4 and LYK5 compromised the beneficial effect of SA187 on Arabidopsis, while it was enhanced in lyk4 mutant plants. Transcriptome analysis revealed that the role of LYK4 is intertwined with a function in remodelling defence responses with growth and root developmental processes. LYK4 interferes with modification of plant ethylene homeostasis by Enterobacter SA187 to boost salt stress resistance. Collectively, these results contribute to unlock the crosstalk between components of the plant immune system and beneficial microbes and point to a new role for the Lys‐motif receptor LYK4 in beneficial plant–microbe interaction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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14. Characterization of a nitrate-permeable channel able to mediate sustained anion efflux in hypocotyl cells from Arabidopsis thaliana
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Frachisse, Jean-Marie, Colcombet, Jean, Guern, Jean, and Barbier-Brygoo, Hélène
- Published
- 2000
15. Biochemical and Genetic Interactions of Phospholipase D Alpha 1 and Mitogen-Activated Protein Kinase 3 Affect Arabidopsis Stress Response.
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Vadovič, Pavol, Šamajová, Olga, Takáč, Tomáš, Novák, Dominik, Zapletalová, Veronika, Colcombet, Jean, and Šamaj, Jozef
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PHOSPHOLIPASE D - Abstract
Phospholipase D alpha 1 (PLDα1, AT3G15730) and mitogen-activated protein kinases (MAPKs) participate on signaling-dependent events in plants. MAPKs are able to phosphorylate a wide range of substrates putatively including PLDs. Here we have focused on functional regulations of PLDα1 by interactions with MAPKs, their co-localization and impact on salt stress and abscisic acid (ABA) tolerance in Arabidopsis. Yeast two-hybrid and bimolecular fluorescent assays showed that PLDα1 interacts with MPK3. Immunoblotting analyses likewise confirmed connection between both these enzymes. Subcellularly we co-localized PLDα1 with MPK3 in the cortical cytoplasm close to the plasma membrane and in cytoplasmic strands. Moreover, genetic interaction studies revealed that pldα1mpk3 double mutant was resistant to a higher salinity and showed a higher tolerance to ABA during germination in comparison to single mutants and wild type. Thus, this study revealed importance of new biochemical and genetic interactions between PLDα1 and MPK3 for Arabidopsis stress (salt and ABA) response. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. Cellular Complexity in MAPK Signaling in Plants: Questions and Emerging Tools to Answer Them.
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Krysan, Patrick J. and Colcombet, Jean
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MITOGEN-activated protein kinases ,PLANT phosphorylation ,MICROSCOPY - Abstract
Mitogen activated protein kinase (MAPK) cascades play an important role in many aspects of plant growth, development, and environmental response. Because of their central role in many important processes, MAPKs have been extensively studied using biochemical and genetic approaches. This work has allowed for the identification of the MAPK genes and proteins involved in a number of different signaling pathways. Less well developed, however, is our understanding of how MAPK cascades and their corresponding signaling pathways are organized at subcellular levels. In this review, we will provide an overview of plant MAPK signaling, including a discussion of what is known about cellular mechanisms for achieving signaling specificity. Then we will explore what is currently known about the subcellular localization of MAPK proteins in resting conditions and after pathway activation. Finally, we will discuss a number of new experimental methods that have not been widely deployed in plants that have the potential to provide a deeper understanding of the spatial and temporal dynamics of MAPK signaling. [ABSTRACT FROM AUTHOR]
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- 2018
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17. Gene Expression Pattern and Protein Localization of Arabidopsis Phospholipase D Alpha 1 Revealed by Advanced Light-Sheet and Super-Resolution Microscopy.
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Novák, Dominik, Vadovič, Pavol, Ovečka, Miroslav, Šamajová, Olga, Komis, George, Colcombet, Jean, and Šamaj, Jozef
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ARABIDOPSIS ,PHOSPHOLIPASE D ,GENE expression in plants - Abstract
Phospholipase D alpha 1 (PLDα1, At3g15730) and its product phosphatidic acid (PA) are involved in a variety of cellular and physiological processes, such as cytoskeletal remodeling, regulation of stomatal closure and opening, as well as biotic and abiotic stress signaling. Here we aimed to study developmental expression patterns and subcellular localization of PLDα1 in Arabidopsis using advanced microscopy methods such as light-sheet fluorescencemicroscopy (LSFM) and structured illumination microscopy (SIM). We complemented two knockout pldα1 mutants with a YFP-tagged PLDα1 expressed under the PLDα1 native promoter in order to study developmental expression pattern and subcellular localization of PLDα1 in Arabidopsis thaliana under natural conditions. Imaging of tissue-specific and developmentally-regulated localization of YFP-tagged PLDα1 by LSFM in roots of growing seedlings showed accumulation of PLDα1-YFP in the root cap and the rhizodermis. Expression of PLDα1-YFP in the rhizodermis was considerably higher in trichoblasts before and during root hair formation and growth. Thus, PLDα1-YFP accumulated in emerging root hairs and in the tips of growing root hairs. PLDα1-YFP showed cytoplasmic subcellular localization in root cap cells and in cells of the root transition zone. In aerial parts of plants PLDα1-YFP was also localized in the cytoplasm showing enhanced accumulation in the cortical cytoplasmic layer of epidermal non-dividing cells of hypocotyls, leaves, and leaf petioles. However, in dividing cells of root apical meristem and leaf petiole epidermis PLDα1-YFP was enriched in mitotic spindles and phragmoplasts, as revealed by co-visualization with microtubules. Finally, super-resolution SIM imaging revealed association of PLDα1-YFP with both microtubules and clathrin-coated vesicles (CCVs) and pits (CCPs). In conclusion, this study shows the developmentally-controlled expression and subcellular localization of PLDα1 in dividing and non-dividing Arabidopsis cells. [ABSTRACT FROM AUTHOR]
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- 2018
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18. Ethylene induced plant stress tolerance by Enterobacter sp. SA187 is mediated by 2‐keto‐4‐methylthiobutyric acid production.
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de Zélicourt, Axel, Synek, Lukas, Saad, Maged M., Alzubaidy, Hanin, Jalal, Rewaa, Xie, Yakun, Andrés-Barrao, Cristina, Rolli, Eleonora, Guerard, Florence, Mariappan, Kiruthiga G., Daur, Ihsanullah, Colcombet, Jean, Benhamed, Moussa, Depaepe, Thomas, Van Der Straeten, Dominique, and Hirt, Heribert
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PHYSIOLOGICAL effects of ethylene ,PHYSIOLOGICAL stress ,ENTEROBACTER ,BUTYRIC acid ,PLANT species ,ABIOTIC stress - Abstract
Several plant species require microbial associations for survival under different biotic and abiotic stresses. In this study, we show that Enterobacter sp. SA187, a desert plant endophytic bacterium, enhances yield of the crop plant alfalfa under field conditions as well as growth of the model plant Arabidopsis thaliana in vitro, revealing a high potential of SA187 as a biological solution for improving crop production. Studying the SA187 interaction with Arabidopsis, we uncovered a number of mechanisms related to the beneficial association of SA187 with plants. SA187 colonizes both the surface and inner tissues of Arabidopsis roots and shoots. SA187 induces salt stress tolerance by production of bacterial 2-keto-4-methylthiobutyric acid (KMBA), known to be converted into ethylene. By transcriptomic, genetic and pharmacological analyses, we show that the ethylene signaling pathway, but not plant ethylene production, is required for KMBA-induced plant salt stress tolerance. These results reveal a novel molecular communication process during the beneficial microbe-induced plant stress tolerance. [ABSTRACT FROM AUTHOR]
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- 2018
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19. MAPK-triggered chromatin reprogramming by histone deacetylase in plant innate immunity.
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Latrasse, David, Jégu, Teddy, Huchen Li, de Zelicourt, Axel, Raynaud, Cécile, Legras, Stéphanie, Gust, Andrea, Samajova, Olga, Veluchamy, Alaguraj, Rayapuram, Naganand, Ramirez-Prado, Juan Sebastian, Kulikova, Olga, Colcombet, Jean, Bigeard, Jean, Genot, Baptiste, Bisseling, Ton, Benhamed, Moussa, and Hirt, Heribert
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- 2017
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20. Convergence of Multiple MAP3Ks on MKK3 Identifies a Set of Novel Stress MAPK Modules.
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Colcombet, Jean, Sözen, Cécile, and Hirt, Heribert
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MITOGEN-activated protein kinases ,PLANT adaptation ,GENETIC transcription - Abstract
Since its first description in 1995 and functional characterization 12 years later, plant MKK3-type MAP2Ks have emerged as important integrators in plant signaling. Although they have received less attention than the canonical stress-activated mitogen-activated protein kinases (MAPKs), several recent publications shed light on their important roles in plant adaptation to environmental conditions. Nevertheless, the MKK3-related literature is complicated. This review summarizes the current knowledge and discrepancies on MKK3 MAPK modules in plants and highlights the singular role of MKK3 in green plants. In the light of the latest data, we hypothesize a general model that all clade-III MAP3Ks converge on MKK3 and C-group MAPKs, thereby defining a set of novel MAPK modules which are activated by stresses and internal signals through the transcriptional regulation of MAP3K genes. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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21. The Role of MAPK Modules and ABA during Abiotic Stress Signaling.
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de Zelicourt, Axel, Colcombet, Jean, and Hirt, Heribert
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MITOGEN-activated protein kinases , *ABSCISIC acid , *ABIOTIC stress , *PLANTS & the environment , *PLANT hormones , *PLANT physiology , *GENETIC regulation in plants - Abstract
To respond to abiotic stresses, plants have developed specific mechanisms that allow them to rapidly perceive and respond to environmental changes. The phytohormone abscisic acid (ABA) was shown to be a pivotal regulator of abiotic stress responses in plants, triggering major changes in plant physiology. The ABA core signaling pathway largely relies on the activation of SnRK2 kinases to mediate several rapid responses, including gene regulation, stomatal closure, and plant growth modulation. Mitogen-activated protein kinases (MAPKs) have also been implicated in ABA signaling, but an entire ABA-activated MAPK module was uncovered only recently. In this review, we discuss the evidence for a role of MAPK modules in the context of different plant ABA signaling pathways. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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22. Signaling Mechanisms in Pattern-Triggered Immunity (PTI).
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Bigeard, Jean, Colcombet, Jean, and Hirt, Heribert
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PROTEIN kinases , *HOST plants , *PLANT diseases , *IMMUNITY , *MITOGENS - Abstract
In nature, plants constantly have to face pathogen attacks. However, plant disease rarely occurs due to efficient immune systems possessed by the host plants. Pathogens are perceived by two different recognition systems that initiate the so-called pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), both of which are accompanied by a set of induced defenses that usually repel pathogen attacks. Here we discuss the complex network of signaling pathways occurring during PTI, focusing on the involvement of mitogen-activated protein kinases. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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23. The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells.
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Neumann, Christina, Fraiture, Malou, Hernàndez-Reyes, Casandra, Akum, Fidele N., Virlogeux-Payant, Isabelle, Ying Chen, Pateyron, Stephanie, Colcombet, Jean, Kogel, Karl-Heinz, Hirt, Heribert, Brunner, Frédéric, and Schikora, Adam
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SALMONELLA ,BACTERIAL proteins ,PHOSPHOTHREONINE ,PLANT cells & tissues ,FOOD poisoning ,IMMUNE system ,PLANT-pathogen relationships ,PROTEIN kinases - Abstract
Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6), thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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24. Functional analysis of Arabidopsis immune-related MAPKs uncovers a role for MPK3 as negative regulator of inducible defenses.
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Frei dit Frey, Nicolas, Garcia, Ana Victoria, Bigeard, Jean, Zaag, Rim, Bueso, Eduardo, Garmier, Marie, Pateyron, Stéphanie, de Tauzia-Moreau, Marie-Ludivine, Brunaud, Véronique, Balzergue, Sandrine, Colcombet, Jean, Aubourg, Sébastien, Martin-Magniette, Marie-Laure, and Hirt, Heribert
- Published
- 2014
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25. Systematic study of subcellular localization of Arabidopsis PPR proteins confirms a massive targeting to organelles.
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Colcombet, Jean, Lopez-Obando, Mauricio, Heurtevin, Laure, Bernard, Clément, Martin, Karine, Berthomé, Richard, and Lurin, Claire
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- 2013
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26. R type anion channel.
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Diatloff, Eugene, Peyronnet, Rémi, Colcombet, Jean, Thomine, Sébastien, Barbier-Brygoo, Hélène, and Frachisse, Jean-Marie
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- 2010
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27. MAP Kinase MPK4 Is Required for Cytokinesis in Arabidopsis thaliana.
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Kosetsu, Ken, Matsunaga, Sachihiro, Nakagami, Hirofumi, Colcombet, Jean, Sasabe, Michiko, Soyano, Takashi, Takahashi, Yuji, Hirt, Heribert, and Machida, Yasunori
- Subjects
MITOGEN-activated protein kinases ,CYTOKINESIS ,ARABIDOPSIS thaliana - Abstract
Cytokinesis in plants is achieved by the formation of the cell plate. A pathway that includes mitogen-activated protein (MAP) kinase kinase kinase and MAP kinase kinase (MAPKK) plays a key role in the control of plant cytokinesis. We show here that a MAP kinase, MPK4, is required for the formation of the cell plate in Arabidopsis thaliana. Single mutations in MPK4 caused dwarfism and characteristic defects in cytokinesis, such as immature cell plates, which became much more prominent upon introduction of a mutation in MKK6/ANQ , the MAPKK for cytokinesis, into mpk4. MKK6/ANQ strongly activated MPK4 in protoplasts, and kinase activity of MPK4 was detected in wild-type tissues that contained dividing cells but not in mkk6/anq mutants. Fluorescent protein–fused MPK4 localized to the expanding cell plates in cells of root tips. Expansion of the cell plates in mpk4 root tips appeared to be retarded. The level of MPK11 transcripts was markedly elevated in mpk4 plants, and defects in the mpk4 mpk11 double mutant with respect to growth and cytokinesis were more severe than in the corresponding single mutants. These results indicate that MPK4 is the downstream target of MKK6/ANQ in the regulation of cytokinesis in Arabidopsis and that MPK11 is also involved in cytokinesis. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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28. R-type anion channel activation is an essential step for ROS-dependent innate immune response in Arabidopsissuspension cells.
- Author
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Colcombet, Jean, Mathieu, Yves, Peyronnet, Remi, Agier, Nicolas, Lelièvre, Françoise, Barbier-Brygoo, Hélène, and Frachisse, Jean-Marie
- Subjects
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ARABIDOPSIS , *ION channels , *PLANT cells & tissues , *OXYGEN in the body , *PLANT immunology , *CELL suspensions , *PLANT adaptation , *EFFECT of stress on plants - Abstract
Plants are constantly exposed to environmental biotic and abiotic stresses. Plants cells perceive these factors and trigger early responses followed by delayed and complex adaptation processes. Using cell suspensions of Arabidopsis thaliana(L.) as a cellular model, we investigated the role of plasma membrane anion channels in Reactive Oxygen Species (ROS) production and in cell death which occurs during non-host pathogen infection. Protoplasts derived from Arabidopsissuspension cells display two anion currents with characteristics very similar to those of the slow nitrate-permeable (S-type) and rapid sulfate-permeable (R-type) channels previously characterised in hypocotyl cells and other cell types. Using seven inhibitors, we showed that the R-type channel and ROS formation in cell cultures present similar pharmacological profiles. The efficiency of anion channel blockers to inhibit ROS production was independent of the nature of the triggering signal (osmotic stress or general elicitors of plant defence), indicating that the R-type channel represents a crossroad in the signalling pathways leading to ROS production. In a second step, we show that treatment with R-type channel blockers accelerates cell death triggered by the non-specific plant pathogen Xanthomonas campestris. Finally, we discuss the hypothesis that the R-type channel is involved in innate immune response allowing cell defence via antibacterial ROS production. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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29. Characterization of nitrate-permeable channel able to mediate sustained anion efflux in hypocotyl cells from Arabidopsis thaliana.
- Author
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Frachisse, Jean-Marie, Colcombet, Jean, Guern, Jean, and Barbier-Brygoo, Helene
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ION channels , *ARABIDOPSIS thaliana - Abstract
Examines the characterization of anionic channel in hypocotyl cells of Arabidopsis thaliana. Need of cytosolic adenosine triphosphate for the activation of the channel; Inhibition of the current by staurosporin; Ability of the channel to mediate anion efflux.
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- 2000
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30. Sustained Incompatibility between MAPK Signaling and Pathogen Effectors.
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Lang, Julien and Colcombet, Jean
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MITOGEN-activated protein kinases , *CHEMICAL plants , *ABIOTIC stress , *PATHOGENIC microorganisms , *PHYTOPATHOGENIC microorganisms , *PLANT defenses - Abstract
In plants, Mitogen-Activated Protein Kinases (MAPKs) are important signaling components involved in developemental processes as well as in responses to biotic and abiotic stresses. In this review, we focus on the roles of MAPKs in Effector-Triggered Immunity (ETI), a specific layer of plant defense responses dependent on the recognition of pathogen effector proteins. Having inspected the literature, we synthesize the current state of knowledge concerning this topic. First, we describe how pathogen effectors can manipulate MAPK signaling to promote virulence, and how in parallel plants have developed mechanisms to protect themselves against these interferences. Then, we discuss the striking finding that the recognition of pathogen effectors can provoke a sustained activation of the MAPKs MPK3/6, extensively analyzing its implications in terms of regulation and functions. In line with this, we also address the question of how a durable activation of MAPKs might affect the scope of their substrates, and thereby mediate the emergence of possibly new ETI-specific responses. By highlighting the sometimes conflicting or missing data, our intention is to spur further research in order to both consolidate and expand our understanding of MAPK signaling in immunity. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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31. MAP4K4 associates with BIK1 to regulate plant innate immunity.
- Author
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Jiang, Yunhe, Han, Baoda, Zhang, Huoming, Mariappan, Kiruthiga G, Bigeard, Jean, Colcombet, Jean, and Hirt, Heribert
- Abstract
To perceive pathogens, plants employ pattern recognition receptor (PRR) complexes, which then transmit these signals via the receptor‐like cytoplasmic kinase BIK1 to induce defense responses. How BIK1 activity and stability are controlled is still not completely understood. Here, we show that the Hippo/STE20 homolog MAP4K4 regulates BIK1‐mediated immune responses. MAP4K4 associates and phosphorylates BIK1 at Ser233, Ser236, and Thr242 to ensure BIK1 stability and activity. Furthermore, MAP4K4 phosphorylates PP2C38 at Ser77 to enable flg22‐induced BIK1 activation. Our results uncover that a Hippo/STE20 homolog, MAP4K4, maintains the homeostasis of the central immune component BIK1. Synopsis: The receptor‐like cytoplasmic kinase BIK1 serves as a central signaling hub during PAMP‐triggered immunity in plants. The kinase MAP4K4 targets and phosphorylates BIK1, thereby stabilizing the protein, and promoting BIK1 activation. MAP4K4 is required for flg22‐triggered immune responses.MAP4K4 binds and phosphorylates BIK1 at Ser233, Ser236 and Thr242 to promote its stability and activity.MAP4K4 phosphorylates PP2C38 at Ser77 to promote flg22‐induced BIK1 activation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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32. Constitutive activity of the Arabidopsis MAP Kinase 3 confers resistance to Pseudomonas syringae and drives robust immune responses.
- Author
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Lang, Julien, Genot, Baptiste, Hirt, Heribert, and Colcombet, Jean
- Published
- 2017
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33. Constitutively active MPK4 helps to clarify its role in plant immunity.
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Colcombet, Jean, Berriri, Souha, and Hirt, Heribert
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- 2013
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34. Plant MAPK cascades: Just rapid signaling modules?
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Boudsocq, Marie, Danquah, Agyemang, de Zélicourt, Axel, Hirt, Heribert, and Colcombet, Jean
- Published
- 2015
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- View/download PDF
35. PlantACT! – how to tackle the climate crisis.
- Author
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Hirt, Heribert, Al-Babili, Salim, Almeida-Trapp, Marilia, Martin, Antoine, Aranda, Manuel, Bartels, Dorothea, Bennett, Malcolm, Blilou, Ikram, Boer, Damian, Boulouis, Alix, Bowler, Chris, Brunel-Muguet, Sophie, Chardon, Fabien, Colcombet, Jean, Colot, Vincent, Daszkowska-Golec, Agata, Dinneny, Jose R., Field, Ben, Froehlich, Katja, and Gardener, Catherine H.
- Subjects
- *
BOTANISTS , *SUSTAINABLE agriculture , *CLIMATE change mitigation , *GREENHOUSE gases , *FERTILIZERS , *PADDY fields - Abstract
Agriculture contributes to global climate change by producing 20–25% of greenhouse gases (GHGs). CO 2 is released from deforestation and land conversion, methane from rice paddy fields, and nitrous oxides from overfertilization. An increasing world population requires a change in the agro food systems, including a reduction in chemical fertilizers and pesticides as well as the production and access to food. Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Arabidopsis SOMATIC EMBRYOGENESIS RECEPTOR KINASES1 and 2 Are Essential for Tapetum Development and Microspore Maturation[W],[OA].
- Author
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Colcombet, Jean, Boisson-Dernier, Aurélien, Ros-Palau, Roc, Vera, Carlos E., and Schroeder, Julian I.
- Subjects
- *
ARABIDOPSIS thaliana , *SOMATIC embryogenesis , *PLANT cell culture , *SEED pods , *POLLEN - Abstract
Among the >200 members of the leucine-rich repeat receptor kinase family in Arabidopsis thaliana, only a few have been functionally characterized. Here, we report a critical function in anther development for the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 (SERK1) and SERK2 genes. Both SERK1 and SERK2 are expressed widely in locules until stage 6 anthers and are more concentrated in the tapetal cell layer later. Whereas serk1 and serk2 single insertion mutants did not show developmental phenotypes, serk1 serk2 double mutants were not able to produce seeds because of a lack of pollen development in mutant anthers. In young buds, double mutant anthers developed normally, but serk1 serk2 microsporangia produced more sporogenous cells that were unable to develop beyond meiosis. Furthermore, serk1 serk2 double mutants developed only three cell layers surrounding the sporogenous cell mass, whereas wild-type anthers developed four cell layers. Further confocal microscopic and molecular analyses showed that serk1 serk2 double mutant anthers lack development of the tapetal cell layer, which accounts for the microspore abortion and male sterility. Taken together, these findings demonstrate that the SERK1 and SERK2 receptor kinases function redundantly as an important control point for sporophytic development controlling male gametophyte prod [ABSTRACT FROM AUTHOR]
- Published
- 2005
37. Arabidopsis SOMATIC EMBRYOGENESIS RECEPTOR KINASES1 and 2 Are Essential for Tapetum Development and Microspore Maturation[W],[OA].
- Author
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Colcombet, Jean, Boisson-Dernier, Aurélien, Ros-Palau, Roc, Vera, Carlos E., and Schroeder, Julian I.
- Subjects
ARABIDOPSIS thaliana ,SOMATIC embryogenesis ,PLANT cell culture ,SEED pods ,POLLEN - Abstract
Among the >200 members of the leucine-rich repeat receptor kinase family in Arabidopsis thaliana, only a few have been functionally characterized. Here, we report a critical function in anther development for the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 (SERK1) and SERK2 genes. Both SERK1 and SERK2 are expressed widely in locules until stage 6 anthers and are more concentrated in the tapetal cell layer later. Whereas serk1 and serk2 single insertion mutants did not show developmental phenotypes, serk1 serk2 double mutants were not able to produce seeds because of a lack of pollen development in mutant anthers. In young buds, double mutant anthers developed normally, but serk1 serk2 microsporangia produced more sporogenous cells that were unable to develop beyond meiosis. Furthermore, serk1 serk2 double mutants developed only three cell layers surrounding the sporogenous cell mass, whereas wild-type anthers developed four cell layers. Further confocal microscopic and molecular analyses showed that serk1 serk2 double mutant anthers lack development of the tapetal cell layer, which accounts for the microspore abortion and male sterility. Taken together, these findings demonstrate that the SERK1 and SERK2 receptor kinases function redundantly as an important control point for sporophytic development controlling male gametophyte prod [ABSTRACT FROM AUTHOR]
- Published
- 2005
38. Review: Mitogen-Activated Protein Kinases in nutritional signaling in Arabidopsis.
- Author
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Chardin, Camille, Schenk, Sebastian T., Hirt, Heribert, Colcombet, Jean, and Krapp, Anne
- Subjects
- *
MITOGEN-activated protein kinases , *ARABIDOPSIS , *PLANT nutrition , *EUKARYOTIC cells , *PHYSIOLOGICAL stress , *PLANT development , *GENE expression in plants - Abstract
Mitogen-Activated Protein Kinase (MAPK) cascades are functional modules widespread among eukaryotic organisms. In plants, these modules are encoded by large multigenic families and are involved in many biological processes ranging from stress responses to cellular differentiation and organ development. Furthermore, MAPK pathways are involved in the perception of environmental and physiological modifications. Interestingly, some MAPKs play a role in several signaling networks and could have an integrative function for the response of plants to their environment. In this review, we describe the classification of MAPKs and highlight some of their biochemical actions. We performed an in silico analysis of MAPK gene expression in response to nutrients supporting their involvement in nutritional signaling. While several MAPKs have been identified as players in sugar, nitrogen, phosphate, iron and potassium-related signaling pathways, their biochemical functions are yet mainly unknown. The integration of these regulatory cascades in the current understanding of nutrient signaling is discussed and potential new avenues for approaches toward plants with higher nutrient use efficiencies are evoked. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
39. In vivo identification of putative CPK5 substrates in Arabidopsis thaliana.
- Author
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Yip Delormel, Tiffany, Avila-Ospina, Liliana, Davanture, Marlène, Zivy, Michel, Lang, Julien, Valentin, Nicolas, Rayapuram, Naganand, Hirt, Heribert, Colcombet, Jean, and Boudsocq, Marie
- Subjects
- *
ARABIDOPSIS thaliana , *PROTEIN kinases , *ABIOTIC stress , *GENE expression , *PHOSPHOPEPTIDES - Abstract
• Transgenic lines expressing a constitutively active form of AtCPK5 induce cell death and target gene expression. • Five new putative AtCPK5 substrates were identified by a phosphoproteomic approach. • The 5 candidates were validated as direct targets of AtCPK5 by in vitro kinase assays. • AtCPK5 interacted with the candidates in cytosol, membranes or nucleus. Calcium signaling mediates most developmental processes and stress responses in plants. Among plant calcium sensors, the calcium-dependent protein kinases display a unique structure harboring both calcium sensing and kinase responding activities. AtCPK5 is an essential member of this family in Arabidopsis that regulates immunity and abiotic stress tolerance. To understand the underlying molecular mechanisms, we implemented a biochemical approach to identify in vivo substrates of AtCPK5. We generated transgenic lines expressing a constitutively active form of AtCPK5 under the control of a dexamethasone-inducible promoter. Lines expressing a kinase-dead version were used as a negative control. By comparing the phosphoproteome of the kinase-active and kinase-dead lines upon dexamethasone treatment, we identified 5 phosphopeptides whose abundance increased specifically in the kinase-active lines. Importantly, we showed that all 5 proteins were phosphorylated in vitro by AtCPK5 in a calcium-dependent manner, suggesting that they are direct targets of AtCPK5. We also detected several interaction patterns between the kinase and the candidates in the cytosol, membranes or nucleus, consistent with the ubiquitous localization of AtCPK5. Finally, we further validated the two phosphosites S245 and S280 targeted by AtCPK5 in the E3 ubiquitin ligase ATL31. Altogether, those results open new perspectives to decipher AtCPK5 biological functions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
40. The MKK3 MAPK cascade integrates temperature and after-ripening signals to modulate seed germination.
- Author
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Otani M, Tojo R, Regnard S, Zheng L, Hoshi T, Ohmori S, Tachibana N, Sano T, Koshimizu S, Ichimura K, Colcombet J, and Kawakami N
- Subjects
- MAP Kinase Kinase 3 metabolism, MAP Kinase Kinase 3 genetics, MAP Kinase Signaling System physiology, Mitogen-Activated Protein Kinases metabolism, Mitogen-Activated Protein Kinases genetics, Plant Dormancy genetics, Plant Dormancy physiology, Signal Transduction, Temperature, Arabidopsis genetics, Arabidopsis metabolism, Arabidopsis growth & development, Arabidopsis Proteins metabolism, Arabidopsis Proteins genetics, Gene Expression Regulation, Plant, Germination, Seeds growth & development, Seeds metabolism, Seeds genetics
- Abstract
The timing of seed germination is controlled by the combination of internal dormancy and external factors. Temperature is a major environmental factor for seed germination. The permissive temperature range for germination is narrow in dormant seeds and expands during after-ripening (AR) (dormancy release). Quantitative trait loci analyses of preharvest sprouting in cereals have revealed that MKK3, a mitogen-activated protein kinase (MAPK) cascade protein, is a negative regulator of grain dormancy. Here, we show that the MAPKKK19/20-MKK3-MPK1/2/7/14 cascade modulates the germination temperature range in Arabidopsis seeds by elevating the germinability of the seeds at sub- and supraoptimal temperatures. The expression of MAPKKK19 and MAPKKK20 is induced around optimal temperature for germination in after-ripened seeds but repressed in dormant seeds. MPK7 activation depends on the expression levels of MAPKKK19/20 , with expression occurring under conditions permissive for germination. Abscisic acid (ABA) and gibberellin (GA) are two major phytohormones which are involved in germination control. Activation of the MKK3 cascade represses ABA biosynthesis enzyme gene expression and induces expression of ABA catabolic enzyme and GA biosynthesis enzyme genes, resulting in expansion of the germinable temperature range. Our data demonstrate that the MKK3 cascade integrates temperature and AR signals to phytohormone metabolism and seed germination., Competing Interests: Competing interests statement:The authors declare no competing interest.
- Published
- 2024
- Full Text
- View/download PDF
41. The MKK3 module integrates nitrate and light signals to modulate secondary dormancy in Arabidopsis thaliana .
- Author
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Regnard S, Otani M, Keruzore M, Teinturier A, Blondel M, Kawakami N, Krapp A, and Colcombet J
- Subjects
- Abscisic Acid metabolism, Light, Seeds growth & development, Seeds genetics, Signal Transduction, Arabidopsis genetics, Arabidopsis metabolism, Arabidopsis physiology, Arabidopsis Proteins metabolism, Arabidopsis Proteins genetics, Gene Expression Regulation, Plant, Germination genetics, MAP Kinase Kinase 3 metabolism, MAP Kinase Kinase 3 genetics, Nitrates metabolism, Plant Dormancy genetics
- Abstract
Seed dormancy corresponds to a reversible blockage of germination. Primary dormancy is established during seed maturation, while secondary dormancy is set up on the dispersed seed, following an exposure to unfavorable factors. Both dormancies are relieved in response to environmental factors, such as light, nitrate, and coldness. Quantitive Trait Locus (QTL) analyses for preharvest sprouting identified MKK3 kinase in cereals as a player in dormancy control. Here, we showed that MKK3 also plays a role in secondary dormancy in Arabidopsis within a signaling module composed of MAP3K13/14/19/20, MKK3, and clade-C MAPKs. Seeds impaired in this module acquired heat-induced secondary dormancy more rapidly than wild-type (WT) seeds, and this dormancy is less sensitive to nitrate, a signal able to release dormancy. We also demonstrated that MPK7 was strongly activated in the seed during dormancy release, especially in response to light and nitrate. This activation was greatly reduced in map3 k13/14/19/20 and mkk3 mutants. Finally, we showed that the module was not regulated and apparently did not regulate the genes controlling abscisic acid/gibberellin acid hormone balance, one of the crucial mechanisms of seed dormancy control. Overall, our work identified a MAPK module controlling seed germination and enlarged the panel of functions of the MKK3-related modules in plants., Competing Interests: Competing interests statement:The authors declare no competing interest.
- Published
- 2024
- Full Text
- View/download PDF
42. Wounding and Insect Feeding Trigger Two Independent MAPK Pathways with Distinct Regulation and Kinetics.
- Author
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Sözen C, Schenk ST, Boudsocq M, Chardin C, Almeida-Trapp M, Krapp A, Hirt H, Mithöfer A, and Colcombet J
- Subjects
- Animals, Arabidopsis genetics, Arabidopsis Proteins genetics, Cyclopentanes metabolism, Gene Expression Regulation, Plant genetics, Gene Expression Regulation, Plant physiology, Kinetics, Mitogen-Activated Protein Kinases genetics, Oxylipins metabolism, Signal Transduction genetics, Signal Transduction physiology, Spodoptera pathogenicity, Nicotiana genetics, Nicotiana metabolism, Arabidopsis metabolism, Arabidopsis Proteins metabolism, Mitogen-Activated Protein Kinases metabolism
- Abstract
Abiotic and biotic factors cause plant wounding and trigger complex short- and long-term responses at the local and systemic levels. These responses are under the control of complex signaling pathways, which are still poorly understood. Here, we show that the rapid activation of clade-A mitogen-activated protein kinases (MAPKs) MPK3 and MPK6 by wounding depends on the upstream MAPK kinases MKK4 and MKK5 but is independent of jasmonic acid (JA) signaling. In addition, this fast module does not control wound-triggered JA accumulation in Arabidopsis ( Arabidopsis thaliana ), unlike its orthologs in tobacco. We also demonstrate that a second MAPK module, composed of MKK3 and the clade-C MAPKs MPK1/2/7, is activated by wounding in a MKK4/5-independent manner. We provide evidence that the activation of this MKK3-MPK1/2/7 module occurs mainly through wound-induced JA production via the transcriptional regulation of upstream clade-III MAP3Ks, particularly MAP3K14. We show that mkk3 mutant plants are more susceptible to herbivory from larvae of the generalist lepidopteran herbivore Spodoptera littoralis , indicating that the MKK3-MPK1/2/7 module is involved in counteracting insect feeding., (© 2020 American Society of Plant Biologists. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
43. Plant Immunity: The MTI-ETI Model and Beyond.
- Author
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Alhoraibi H, Bigeard J, Rayapuram N, Colcombet J, and Hirt H
- Subjects
- Biomarkers, Models, Biological, Pathogen-Associated Molecular Pattern Molecules metabolism, Plants genetics, Plants immunology, Plants metabolism, Plants microbiology, Signal Transduction, Host Microbial Interactions immunology, Plant Immunity, Plant Physiological Phenomena
- Abstract
In plant-microbe interactions, a pathogenic microbe initially has to overcome preformed and subsequently induced plant defenses. One of the initial host-induced defense responses is microbe-associated molecular pattern (MAMP)-triggered immunity (MTI). Successful pathogens attenuate MTI by delivering various effectors that result in effector-triggered susceptibility and disease. However, some host plants developed mechanisms to detect effectors and can trigger effector-triggered immunity (ETI), thereby abrogating pathogen infection and propagation. Despite the wide acceptance of the above concepts, more and more accumulating evidence suggests that the distinction between MAMPs and effectors and MTI and ETI is often not given. This review discusses the complexity of MTI and ETI signaling networks and elaborates the current state of the art of defining MAMPs versus effectors and MTI versus ETI, but also discusses new findings that challenge the current dichotomy of these concepts.
- Published
- 2019
- Full Text
- View/download PDF
44. Auxin efflux by PIN-FORMED proteins is activated by two different protein kinases, D6 PROTEIN KINASE and PINOID.
- Author
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Zourelidou M, Absmanner B, Weller B, Barbosa IC, Willige BC, Fastner A, Streit V, Port SA, Colcombet J, de la Fuente van Bentem S, Hirt H, Kuster B, Schulze WX, Hammes UZ, and Schwechheimer C
- Subjects
- Animals, Biological Transport, Cell Membrane metabolism, Microscopy, Confocal, Mutation, Oocytes cytology, Oocytes metabolism, Phosphorylation, Xenopus, Arabidopsis metabolism, Arabidopsis Proteins metabolism, Indoleacetic Acids chemistry, Protein Kinases metabolism, Protein Serine-Threonine Kinases metabolism
- Abstract
The development and morphology of vascular plants is critically determined by synthesis and proper distribution of the phytohormone auxin. The directed cell-to-cell distribution of auxin is achieved through a system of auxin influx and efflux transporters. PIN-FORMED (PIN) proteins are proposed auxin efflux transporters, and auxin fluxes can seemingly be predicted based on the--in many cells--asymmetric plasma membrane distribution of PINs. Here, we show in a heterologous Xenopus oocyte system as well as in Arabidopsis thaliana inflorescence stems that PIN-mediated auxin transport is directly activated by D6 PROTEIN KINASE (D6PK) and PINOID (PID)/WAG kinases of the Arabidopsis AGCVIII kinase family. At the same time, we reveal that D6PKs and PID have differential phosphosite preferences. Our study suggests that PIN activation by protein kinases is a crucial component of auxin transport control that must be taken into account to understand auxin distribution within the plant.
- Published
- 2014
- Full Text
- View/download PDF
45. Protein complexes characterization in Arabidopsis thaliana by tandem affinity purification coupled to mass spectrometry analysis.
- Author
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Bigeard J, Pflieger D, Colcombet J, Gérard L, Mireau H, and Hirt H
- Subjects
- Chemical Precipitation, Nickel chemistry, Proteolysis, Trypsin metabolism, Arabidopsis metabolism, Arabidopsis Proteins isolation & purification, Arabidopsis Proteins metabolism, Chromatography, Affinity methods, Mass Spectrometry methods
- Abstract
Proteins are major elements participating in all the key functions of the cells. They rarely fulfill their physiological roles in an autonomous way but rather act as part of more complex cellular machines. Indeed they can bind different types of molecules (proteins, nucleic acids, metabolites, etc.), via stable or transient interactions, depending on their nature and functions. The identification of the molecular partners of a given protein is hence essential to better understand its roles, regulation, and mechanisms of action.This chapter describes the use of a tandem affinity purification approach followed by mass spectrometry analysis to try to identify and characterize the proteins involved in protein complexes in Arabidopsis thaliana and decipher some mechanisms of regulation of the modules. Important elements to consider in such an approach are first extensively exposed in the introduction. This technique, in combination with complementary approaches like yeast two-hybrid and bimolecular fluorescence complementation, can be an interesting source of data to identify and characterize in vivo protein complexes.
- Published
- 2014
- Full Text
- View/download PDF
46. Identification of constitutively active AtMPK6 mutants using a functional screen in Saccharomyces cerevisiae.
- Author
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Hudik E, Berriri S, Hirt H, and Colcombet J
- Subjects
- Arabidopsis genetics, Plasmids genetics, Saccharomyces cerevisiae drug effects, Saccharomyces cerevisiae growth & development, Salts pharmacology, Transformation, Genetic, Arabidopsis enzymology, Arabidopsis Proteins genetics, Genetic Engineering methods, Mitogen-Activated Protein Kinases genetics, Mutation, Saccharomyces cerevisiae genetics
- Abstract
MAPK (Mitogen-Activated Protein Kinases) mutants which are active independently of phosphorylation by upstream MAPK Kinases (MAPKKs) help to clarify signal transduction processes through MAPK modules and provide a useful tool to understand MAPK roles in the cell. The identification of such mutations is tricky. In this chapter, we provide a detailed protocol for their screening, taking advantage of a functional expression assay in yeast.
- Published
- 2014
- Full Text
- View/download PDF
47. Arabidopsis MAPKs: a complex signalling network involved in multiple biological processes.
- Author
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Colcombet J and Hirt H
- Subjects
- Arabidopsis Proteins metabolism, Cytoplasm metabolism, Flagellin metabolism, Immunity, Innate, MAP Kinase Signaling System, Mitogen-Activated Protein Kinases metabolism, Models, Biological, Models, Genetic, Osmosis, Ozone, Phosphorylation, Pollen metabolism, Virulence Factors metabolism, Arabidopsis genetics, Arabidopsis metabolism, Gene Expression Regulation, Plant, Signal Transduction
- Abstract
Many changes in environmental conditions and hormones are mediated by MAPK (mitogen-activated protein kinase) cascades in all eukaryotes, including plants. Studies of MAPK pathways in genetic model organisms are especially informative in revealing the molecular mechanisms by means of which MAPK cascades are controlled and modulate cellular processes. The present review highlights recent insights into MAPK-based signalling in Arabidopsis thaliana (thale cress), revealing the complexity and future challenges to understanding signal-transduction networks on a global scale.
- Published
- 2008
- Full Text
- View/download PDF
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