Antony Buchala | University of Fribourg (original) (raw)
Papers by Antony Buchala
Plant Physiology, 1997
The possible role of the octadecanoid signaling pathway with jasmonic acid (JA) as the central co... more The possible role of the octadecanoid signaling pathway with jasmonic acid (JA) as the central component in defense-gene regulation of pathogen-attacked rice was studied. Rice (Oryza sativa L.) seedlings were treated with JA or inoculated with the rice blast fungus Magnaporthe grisea (Hebert) Barr., and gene-expression patterns were compared between the two treatments. JA application induced the accumulation of a number of pathogenesis-related (PR) gene products at the mRNA and protein levels, but pathogen attack did not enhance the levels of (-)-JA during the time required for PR gene expression. Pathogen-induced accumulation of PR1-like proteins was reduced in plants treated with tetcyclacis, a novel inhibitor of jasmonate biosynthesis. There was an additive and negative interaction between JA and an elicitor from M. grisea with respect to induction of PR1-like proteins and of an abundant JA-and wound-induced protein of 26 kD, respectively. Finally, activation of the octadecanoid ...
![Research paper thumbnail of Methyl jasmonate protects Norway spruce [Picea abies (L.) Karst.] seedlings against Pythium ultimum Trow](https://attachments.academia-assets.com/85091832/thumbnails/1.jpg)
](Physiological and Molecular Plant Pathology, 1999
The effect of methyl jasmonate (MeJA) was tested on the resistance of Picea abies seedlings again... more The effect of methyl jasmonate (MeJA) was tested on the resistance of Picea abies seedlings against Pythium ultimum. Treatments with volatile MeJA during 3 days (25 µl 100 l −" air) protected seedlings up to 75 %. This effect was unlikely to result from a direct fungitoxic effect of MeJA, as under the same conditions of treatment, growth in itro of Pythium ultimum was not affected. Observations of possible changes on histological barriers such as lignin deposits showed no differences between control and treated plants. MeJA induced the accumulation of free salicylic acid (SA) in all parts of the seedlings, whereas bound SA only increased in hypocotyls and cotyledons. An increase in chitinase activity was detected in cotyledons already 2 days after exposure to MeJA. The results suggest that MeJA acts by stimulating defence responses of the host plant. No increase in endogenous jasmonic acid was found in spruce seedlings inoculated with Pythium nor MeJA.
The Plant Journal, 2002
In Arabidopsis, the rhizobacterial strain Pseudomonas¯uorescens WCS417r triggers jasmonate (JA)-a... more In Arabidopsis, the rhizobacterial strain Pseudomonas¯uorescens WCS417r triggers jasmonate (JA)-and ethylene (ET)-dependent induced systemic resistance (ISR) that is effective against different pathogens. Arabidopsis genotypes unable to express rhizobacteria-mediated ISR against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) exhibit enhanced disease susceptibility towards this pathogen. To identify novel components controlling induced resistance, we tested 11 Arabidopsis mutants with enhanced disease susceptibility (eds) to pathogenic P. syringae bacteria for WCS417rmediated ISR and pathogen-induced systemic acquired resistance (SAR). Mutants eds4-1, eds8-1 and eds10-1 failed to develop WCS417r-mediated ISR, while mutants eds5-1 and eds12-1 failed to express pathogen-induced SAR. Whereas eds5-1 is known to be blocked in salicylic acid (SA) biosynthesis, analysis of eds12-1 revealed that its impaired SAR response is caused by reduced sensitivity to this molecule. Analysis of the ISR-impaired eds mutants revealed that they are non-responsive to induction of resistance by methyl jasmonate (MeJA) (eds4-1, eds8-1 and eds10-1), or the ET precursor 1aminocyclopropane-1-carboxylate (ACC) (eds4-1 and eds10-1). Moreover, eds4-1 and eds8-1 showed reduced expression of the plant defensin gene PDF1.2 after MeJA and ACC treatment, which was associated with reduced sensitivity to either ET (eds4-1) or MeJA (eds8-1). Although blocked in WCS417r-, MeJA-and ACC-induced ISR, eds10-1 behaved normally for several other responses to MeJA or ACC. The results indicate that EDS12 is required for SAR and acts downstream of SA, whereas EDS4, EDS8 and EDS10 are required for ISR acting either in JA signalling (EDS8), ET signalling (EDS4), or downstream JA and ET signalling (EDS10) in the ISR pathway.
Planta, 2002
When seedlings of barley (Hordeum vulgare L.) were transferred from a natural light/dark cycle in... more When seedlings of barley (Hordeum vulgare L.) were transferred from a natural light/dark cycle into darkness, (1fi3,1fi4)-b-D-glucan endohydrolase (EC 3.2.1.73) activity in leaf extracts increased 3-to 4-fold after 2 days. Activity decreased to normal levels within a day if the light/dark cycle was restored. Although there are two (1fi3,1fi4)-b-D-glucan endohydrolase isoenzymes in barley, the increased enzyme activity in dark-grown seedlings was attributable entirely to increases in isoenzyme EI. Northern hybridization analyses confirmed that mRNA transcripts encoding (1fi3,1fi4)-b-D-glucan endohydrolase isoenzyme EI accumulated in the leaves of dark-incubated seedlings; no isoenzyme EII mRNA was detected. Activity of b-Dglucan glucohydrolases also increased 10-fold after 2 days of dark treatment. The latter, broad-specificity enzymes release glucose from (1fi3,1fi4)-b-D-glucans and from b-D-oligoglucosides released by (1fi3,1fi4)-b-D-glucan endohydrolases. Consistent with the activity patterns of these enzymes, the (1fi3,1fi4)-b-D-glucan content of leaf cell walls decreased by about 30% when barley seedlings were transferred into darkness. Soluble sugars in the leaves decreased by about 60% during the same period. Because no measurable leaf elongation was detected during the various light/dark treatments, the enzymes were unlikely to be participating in wall loosening and cell elongation. Instead, the results suggest that cell wall (1fi3,1fi4)-b-D-glucans can be re-mobilized in the non-elongating, dark-incubated leaves and the glucose so generated could serve as an energy source under conditions of sugar depletion. Keywords Cell wall AE Dark induction AE (1fi3,1fi4)-b-D-Glucan AE (1fi3, 1fi4)-b-D-Glucan endohydrolase AE b-D-Glucan glucohydrolase AE Hordeum (cell wall)
We are interested in the role of indole glucosinolates (iGS) and the phytoalexin camalexin in dis... more We are interested in the role of indole glucosinolates (iGS) and the phytoalexin camalexin in diseases resistance of Arabidopsis to the oomycete pathogen Phytophthora brassicae. Transcript profiling revealed that many genes involved in iGS or camalexin biosynthesis are up-regulated upon inoculation. Mutants with defects in either iGS metabolism or camalexin accumulation remain resistant to P. brassicae. Interestingly, the combined deficiency in iGS and camalexin in the double mutants cyp79B2 cyp79B3 and pen2-1 pad3-1 results in susceptibility. Hence, Arabidopsis defence against P. brassicae relies on the combined action of iGS and camalexin. The constitutively produced iGS appear to play an early role in penetration resistance whereas the inducible camalexin is important at later stages of the infection.
Adipose tissue plasticity during catch-up fat driven by thrifty metabolism: Relevance for muscle-... more Adipose tissue plasticity during catch-up fat driven by thrifty metabolism: Relevance for muscle-adipose glucose redistribution during catch-up growth
Alois Schweighofer,a Vaiva Kazanaviciute,a Elisabeth Scheikl,a Markus Teige,a Robert Doczi,a Heri... more Alois Schweighofer,a Vaiva Kazanaviciute,a Elisabeth Scheikl,a Markus Teige,a Robert Doczi,a Heribert Hirt,a Manfred Schwanninger,b Merijn Kant,c Robert Schuurink,c Felix Mauch,d Antony Buchala,d Francesca Cardinale,e and Irute Meskienea,1 a Max F. Perutz Laboratories of the University of Vienna, 1030 Vienna, Austria b Department of Chemistry, University of Natural Resources and Applied Life Sciences, 1190 Vienna, Austria c Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 SM Amsterdam, The Netherlands d Département de Biologie, Université de Fribourg, CH-1700 Fribourg, Switzerland e Dipartimento di Valorizzazione e Protezione delle Risorse Agroforestali, Plant Pathology, University of Turin, I-10095 Grugliasco, Italy
International Symposium on Natural Phenols in Plant Resistance, 1994
BMC Plant Biology, 2015
Background: An important signal transduction pathway in plant defence depends on the accumulation... more Background: An important signal transduction pathway in plant defence depends on the accumulation of salicylic acid (SA). SA is produced in chloroplasts and the multidrug and toxin extrusion transporter ENHANCED DISEASE SUSCEPTIBILITY5 (EDS5; At4g39030) is necessary for the accumulation of SA after pathogen and abiotic stress. EDS5 is localized at the chloroplast and functions in transporting SA from the chloroplast to the cytoplasm. EDS5 has a homologue called EDS5H (EDS5 HOMOLOGUE; At2g21340) but its relationship to EDS5 has not been described and its function is not known. Results: EDS5H exhibits about 72 % similarity and 59 % identity to EDS5. In contrast to EDS5 that is induced after pathogen inoculation, EDS5H was constitutively expressed in all green tissues, independently of pathogen infection. Both transporters are located at the envelope of the chloroplast, the compartment of SA biosynthesis. EDS5H is not involved with the accumulation of SA after inoculation with a pathogen or exposure to UV stress. A phylogenetic analysis supports the hypothesis that EDS5H may be an H + /organic acid antiporter like EDS5. Conclusions: The data based on genetic and molecular studies indicate that EDS5H despite its homology to EDS5 does not contribute to pathogen-induced SA accumulation like EDS5. EDS5H most likely transports related substances such as for example phenolic acids, but unlikely SA.
Plant Physiology, 1997
The possible role of the octadecanoid signaling pathway with jasmonic acid (JA) as the central co... more The possible role of the octadecanoid signaling pathway with jasmonic acid (JA) as the central component in defense-gene regulation of pathogen-attacked rice was studied. Rice (Oryza sativa L.) seedlings were treated with JA or inoculated with the rice blast fungus Magnaporthe grisea (Hebert) Barr., and gene-expression patterns were compared between the two treatments. JA application induced the accumulation of a number of pathogenesis-related (PR) gene products at the mRNA and protein levels, but pathogen attack did not enhance the levels of (-)-JA during the time required for PR gene expression. Pathogen-induced accumulation of PR1-like proteins was reduced in plants treated with tetcyclacis, a novel inhibitor of jasmonate biosynthesis. There was an additive and negative interaction between JA and an elicitor from M. grisea with respect to induction of PR1-like proteins and of an abundant JA-and wound-induced protein of 26 kD, respectively. Finally, activation of the octadecanoid ...
Physiological and Molecular Plant Pathology, 1999
The effect of methyl jasmonate (MeJA) was tested on the resistance of Picea abies seedlings again... more The effect of methyl jasmonate (MeJA) was tested on the resistance of Picea abies seedlings against Pythium ultimum. Treatments with volatile MeJA during 3 days (25 µl 100 l −" air) protected seedlings up to 75 %. This effect was unlikely to result from a direct fungitoxic effect of MeJA, as under the same conditions of treatment, growth in itro of Pythium ultimum was not affected. Observations of possible changes on histological barriers such as lignin deposits showed no differences between control and treated plants. MeJA induced the accumulation of free salicylic acid (SA) in all parts of the seedlings, whereas bound SA only increased in hypocotyls and cotyledons. An increase in chitinase activity was detected in cotyledons already 2 days after exposure to MeJA. The results suggest that MeJA acts by stimulating defence responses of the host plant. No increase in endogenous jasmonic acid was found in spruce seedlings inoculated with Pythium nor MeJA.
The Plant Journal, 2002
In Arabidopsis, the rhizobacterial strain Pseudomonas¯uorescens WCS417r triggers jasmonate (JA)-a... more In Arabidopsis, the rhizobacterial strain Pseudomonas¯uorescens WCS417r triggers jasmonate (JA)-and ethylene (ET)-dependent induced systemic resistance (ISR) that is effective against different pathogens. Arabidopsis genotypes unable to express rhizobacteria-mediated ISR against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) exhibit enhanced disease susceptibility towards this pathogen. To identify novel components controlling induced resistance, we tested 11 Arabidopsis mutants with enhanced disease susceptibility (eds) to pathogenic P. syringae bacteria for WCS417rmediated ISR and pathogen-induced systemic acquired resistance (SAR). Mutants eds4-1, eds8-1 and eds10-1 failed to develop WCS417r-mediated ISR, while mutants eds5-1 and eds12-1 failed to express pathogen-induced SAR. Whereas eds5-1 is known to be blocked in salicylic acid (SA) biosynthesis, analysis of eds12-1 revealed that its impaired SAR response is caused by reduced sensitivity to this molecule. Analysis of the ISR-impaired eds mutants revealed that they are non-responsive to induction of resistance by methyl jasmonate (MeJA) (eds4-1, eds8-1 and eds10-1), or the ET precursor 1aminocyclopropane-1-carboxylate (ACC) (eds4-1 and eds10-1). Moreover, eds4-1 and eds8-1 showed reduced expression of the plant defensin gene PDF1.2 after MeJA and ACC treatment, which was associated with reduced sensitivity to either ET (eds4-1) or MeJA (eds8-1). Although blocked in WCS417r-, MeJA-and ACC-induced ISR, eds10-1 behaved normally for several other responses to MeJA or ACC. The results indicate that EDS12 is required for SAR and acts downstream of SA, whereas EDS4, EDS8 and EDS10 are required for ISR acting either in JA signalling (EDS8), ET signalling (EDS4), or downstream JA and ET signalling (EDS10) in the ISR pathway.
Planta, 2002
When seedlings of barley (Hordeum vulgare L.) were transferred from a natural light/dark cycle in... more When seedlings of barley (Hordeum vulgare L.) were transferred from a natural light/dark cycle into darkness, (1fi3,1fi4)-b-D-glucan endohydrolase (EC 3.2.1.73) activity in leaf extracts increased 3-to 4-fold after 2 days. Activity decreased to normal levels within a day if the light/dark cycle was restored. Although there are two (1fi3,1fi4)-b-D-glucan endohydrolase isoenzymes in barley, the increased enzyme activity in dark-grown seedlings was attributable entirely to increases in isoenzyme EI. Northern hybridization analyses confirmed that mRNA transcripts encoding (1fi3,1fi4)-b-D-glucan endohydrolase isoenzyme EI accumulated in the leaves of dark-incubated seedlings; no isoenzyme EII mRNA was detected. Activity of b-Dglucan glucohydrolases also increased 10-fold after 2 days of dark treatment. The latter, broad-specificity enzymes release glucose from (1fi3,1fi4)-b-D-glucans and from b-D-oligoglucosides released by (1fi3,1fi4)-b-D-glucan endohydrolases. Consistent with the activity patterns of these enzymes, the (1fi3,1fi4)-b-D-glucan content of leaf cell walls decreased by about 30% when barley seedlings were transferred into darkness. Soluble sugars in the leaves decreased by about 60% during the same period. Because no measurable leaf elongation was detected during the various light/dark treatments, the enzymes were unlikely to be participating in wall loosening and cell elongation. Instead, the results suggest that cell wall (1fi3,1fi4)-b-D-glucans can be re-mobilized in the non-elongating, dark-incubated leaves and the glucose so generated could serve as an energy source under conditions of sugar depletion. Keywords Cell wall AE Dark induction AE (1fi3,1fi4)-b-D-Glucan AE (1fi3, 1fi4)-b-D-Glucan endohydrolase AE b-D-Glucan glucohydrolase AE Hordeum (cell wall)
We are interested in the role of indole glucosinolates (iGS) and the phytoalexin camalexin in dis... more We are interested in the role of indole glucosinolates (iGS) and the phytoalexin camalexin in diseases resistance of Arabidopsis to the oomycete pathogen Phytophthora brassicae. Transcript profiling revealed that many genes involved in iGS or camalexin biosynthesis are up-regulated upon inoculation. Mutants with defects in either iGS metabolism or camalexin accumulation remain resistant to P. brassicae. Interestingly, the combined deficiency in iGS and camalexin in the double mutants cyp79B2 cyp79B3 and pen2-1 pad3-1 results in susceptibility. Hence, Arabidopsis defence against P. brassicae relies on the combined action of iGS and camalexin. The constitutively produced iGS appear to play an early role in penetration resistance whereas the inducible camalexin is important at later stages of the infection.
Adipose tissue plasticity during catch-up fat driven by thrifty metabolism: Relevance for muscle-... more Adipose tissue plasticity during catch-up fat driven by thrifty metabolism: Relevance for muscle-adipose glucose redistribution during catch-up growth
Alois Schweighofer,a Vaiva Kazanaviciute,a Elisabeth Scheikl,a Markus Teige,a Robert Doczi,a Heri... more Alois Schweighofer,a Vaiva Kazanaviciute,a Elisabeth Scheikl,a Markus Teige,a Robert Doczi,a Heribert Hirt,a Manfred Schwanninger,b Merijn Kant,c Robert Schuurink,c Felix Mauch,d Antony Buchala,d Francesca Cardinale,e and Irute Meskienea,1 a Max F. Perutz Laboratories of the University of Vienna, 1030 Vienna, Austria b Department of Chemistry, University of Natural Resources and Applied Life Sciences, 1190 Vienna, Austria c Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 SM Amsterdam, The Netherlands d Département de Biologie, Université de Fribourg, CH-1700 Fribourg, Switzerland e Dipartimento di Valorizzazione e Protezione delle Risorse Agroforestali, Plant Pathology, University of Turin, I-10095 Grugliasco, Italy
International Symposium on Natural Phenols in Plant Resistance, 1994
BMC Plant Biology, 2015
Background: An important signal transduction pathway in plant defence depends on the accumulation... more Background: An important signal transduction pathway in plant defence depends on the accumulation of salicylic acid (SA). SA is produced in chloroplasts and the multidrug and toxin extrusion transporter ENHANCED DISEASE SUSCEPTIBILITY5 (EDS5; At4g39030) is necessary for the accumulation of SA after pathogen and abiotic stress. EDS5 is localized at the chloroplast and functions in transporting SA from the chloroplast to the cytoplasm. EDS5 has a homologue called EDS5H (EDS5 HOMOLOGUE; At2g21340) but its relationship to EDS5 has not been described and its function is not known. Results: EDS5H exhibits about 72 % similarity and 59 % identity to EDS5. In contrast to EDS5 that is induced after pathogen inoculation, EDS5H was constitutively expressed in all green tissues, independently of pathogen infection. Both transporters are located at the envelope of the chloroplast, the compartment of SA biosynthesis. EDS5H is not involved with the accumulation of SA after inoculation with a pathogen or exposure to UV stress. A phylogenetic analysis supports the hypothesis that EDS5H may be an H + /organic acid antiporter like EDS5. Conclusions: The data based on genetic and molecular studies indicate that EDS5H despite its homology to EDS5 does not contribute to pathogen-induced SA accumulation like EDS5. EDS5H most likely transports related substances such as for example phenolic acids, but unlikely SA.