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Imposed glutathione-mediated redox switch modulates the tobacco wound-induced protein kinase and salicylic acid-induced protein kinase activation state and impacts on defence against Pseudomonas syringae.

Matern S, Peskan-Berghoefer T, Gromes R, Kiesel RV, Rausch T - J. Exp. Bot. (2015)

Bottom Line: Similarly, rapid activation of MAPKs could be induced in WT tobacco by exposure to either reduced or oxidized glutathione.When HGL plants were challenged with adapted or non-adapted Pseudomonas syringae pathovars, the cytosolic redox shift was further amplified and the defence response was markedly increased, showing a priming effect for SA and callose; however, the initial and transient hyperactivation of MAPK signalling was attenuated in HGLs.The results suggest that, in tobacco, MAPK and SA signalling may operate independently, both possibly being modulated by the glutathione redox potential.

View Article: PubMed Central - PubMed

Affiliation: Centre for Organismal Studies Heidelberg, Department of Plant Molecular Physiology, Heidelberg University, 69120 Heidelberg, Germany The Hartmut Hoffmann-Berling International Graduate School of Molecular and Cellular Biology (HBIGS), Heidelberg University, 69120 Heidelberg, Germany.

No MeSH data available.


Related in: MedlinePlus

Infiltration of GSH (10mM) or GSSG (1mM) into leaves of WT tobacco causes significant oxidative shifts in cytosolic redox potential and rapidly activates SIPK and WIPK. (A) GSH and GSSG solutions were infiltrated with a needleless syringe from the abaxial leaf side. After 30min, redox potentials were determined with GRX1-roGFP2 as sensor in three independent samples (see also Fig. 1). Student’s t-test was used to calculate significant differences (**P<0.01) between treatments. (B) Treatment with GSH or GSSG for 30min activates MAPK signalling. Pre-incubation with 10mM N-ethylmaleimide (NEM) for 20min blocked SIPK and WIPK activation in response to GSH, GSSG, or 100nM Flg22 (flagellin N-terminal epitope). (C) Time course of SIPK and WIPK activation with GSH and GSSG over a 2h incubation period compared with mock treatment. Fifteen micrograms of total protein was loaded per lane. For loading control, the membrane was stained with amido black. Experiments were repeated twice with similar results.
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Figure 3: Infiltration of GSH (10mM) or GSSG (1mM) into leaves of WT tobacco causes significant oxidative shifts in cytosolic redox potential and rapidly activates SIPK and WIPK. (A) GSH and GSSG solutions were infiltrated with a needleless syringe from the abaxial leaf side. After 30min, redox potentials were determined with GRX1-roGFP2 as sensor in three independent samples (see also Fig. 1). Student’s t-test was used to calculate significant differences (**P<0.01) between treatments. (B) Treatment with GSH or GSSG for 30min activates MAPK signalling. Pre-incubation with 10mM N-ethylmaleimide (NEM) for 20min blocked SIPK and WIPK activation in response to GSH, GSSG, or 100nM Flg22 (flagellin N-terminal epitope). (C) Time course of SIPK and WIPK activation with GSH and GSSG over a 2h incubation period compared with mock treatment. Fifteen micrograms of total protein was loaded per lane. For loading control, the membrane was stained with amido black. Experiments were repeated twice with similar results.

Mentions: To corroborate the assumption that the observed activation of SIPK and WIPK in HGLs is caused by the increase in cellular glutathione content and/or redox state, leaf discs of WT plants were treated with 10mM GSH or 1mM GSSG. Since GSH is not stable in aqueous solution (Yamamoto and Ishihara, 1994) and is expected to be further oxidized in the apoplast before uptake into the cytosol, treating leaf cells with GSH might, like GSSG, cause an oxidative shift of the cytosolic glutathione redox potential. To test this assumption, leaves of tobacco GRX1-roGFP2 transformants (in a WT background) were infiltrated with 10mM GSH or 1mM GSSG solution, and cytosolic glutathione redox potential was monitored over time. Indeed, both treatments caused shifts towards a more oxidized state (Fig. 3A).


Imposed glutathione-mediated redox switch modulates the tobacco wound-induced protein kinase and salicylic acid-induced protein kinase activation state and impacts on defence against Pseudomonas syringae.

Matern S, Peskan-Berghoefer T, Gromes R, Kiesel RV, Rausch T - J. Exp. Bot. (2015)

Infiltration of GSH (10mM) or GSSG (1mM) into leaves of WT tobacco causes significant oxidative shifts in cytosolic redox potential and rapidly activates SIPK and WIPK. (A) GSH and GSSG solutions were infiltrated with a needleless syringe from the abaxial leaf side. After 30min, redox potentials were determined with GRX1-roGFP2 as sensor in three independent samples (see also Fig. 1). Student’s t-test was used to calculate significant differences (**P<0.01) between treatments. (B) Treatment with GSH or GSSG for 30min activates MAPK signalling. Pre-incubation with 10mM N-ethylmaleimide (NEM) for 20min blocked SIPK and WIPK activation in response to GSH, GSSG, or 100nM Flg22 (flagellin N-terminal epitope). (C) Time course of SIPK and WIPK activation with GSH and GSSG over a 2h incubation period compared with mock treatment. Fifteen micrograms of total protein was loaded per lane. For loading control, the membrane was stained with amido black. Experiments were repeated twice with similar results.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

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Show All Figures
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Figure 3: Infiltration of GSH (10mM) or GSSG (1mM) into leaves of WT tobacco causes significant oxidative shifts in cytosolic redox potential and rapidly activates SIPK and WIPK. (A) GSH and GSSG solutions were infiltrated with a needleless syringe from the abaxial leaf side. After 30min, redox potentials were determined with GRX1-roGFP2 as sensor in three independent samples (see also Fig. 1). Student’s t-test was used to calculate significant differences (**P<0.01) between treatments. (B) Treatment with GSH or GSSG for 30min activates MAPK signalling. Pre-incubation with 10mM N-ethylmaleimide (NEM) for 20min blocked SIPK and WIPK activation in response to GSH, GSSG, or 100nM Flg22 (flagellin N-terminal epitope). (C) Time course of SIPK and WIPK activation with GSH and GSSG over a 2h incubation period compared with mock treatment. Fifteen micrograms of total protein was loaded per lane. For loading control, the membrane was stained with amido black. Experiments were repeated twice with similar results.
Mentions: To corroborate the assumption that the observed activation of SIPK and WIPK in HGLs is caused by the increase in cellular glutathione content and/or redox state, leaf discs of WT plants were treated with 10mM GSH or 1mM GSSG. Since GSH is not stable in aqueous solution (Yamamoto and Ishihara, 1994) and is expected to be further oxidized in the apoplast before uptake into the cytosol, treating leaf cells with GSH might, like GSSG, cause an oxidative shift of the cytosolic glutathione redox potential. To test this assumption, leaves of tobacco GRX1-roGFP2 transformants (in a WT background) were infiltrated with 10mM GSH or 1mM GSSG solution, and cytosolic glutathione redox potential was monitored over time. Indeed, both treatments caused shifts towards a more oxidized state (Fig. 3A).

Bottom Line: Similarly, rapid activation of MAPKs could be induced in WT tobacco by exposure to either reduced or oxidized glutathione.When HGL plants were challenged with adapted or non-adapted Pseudomonas syringae pathovars, the cytosolic redox shift was further amplified and the defence response was markedly increased, showing a priming effect for SA and callose; however, the initial and transient hyperactivation of MAPK signalling was attenuated in HGLs.The results suggest that, in tobacco, MAPK and SA signalling may operate independently, both possibly being modulated by the glutathione redox potential.

View Article: PubMed Central - PubMed

Affiliation: Centre for Organismal Studies Heidelberg, Department of Plant Molecular Physiology, Heidelberg University, 69120 Heidelberg, Germany The Hartmut Hoffmann-Berling International Graduate School of Molecular and Cellular Biology (HBIGS), Heidelberg University, 69120 Heidelberg, Germany.

No MeSH data available.


Related in: MedlinePlus