Mechanisms of survival of necrotrophic fungal plant pathogens in hosts expressing the hypersensitive response

Mayer, Alfred M.; Staples, Richard C.; Gil-ad, Nir L.

doi:10.1016/s0031-9422(01)00187-x

Cited by 173 publications

(120 citation statements)

References 60 publications

Supporting

Mentioning

113

Contrasting

Unclassified

Order By: Relevance

“…Browning of infested roots in several host-pathogen interactions has been associated with increased accumulation of phenolic compounds in affected tissues [51,52]. These phenolic compounds are considered to be involved in plant defense responses [53] such as the hypersensitive reaction in which host cells undergo programmed cell death to block pathogen advance. However, root browning and phenolic compound accumulation in infested roots has also been associated with root necrosis [54,55].…”

Section: Discussionmentioning

confidence: 99%

Root Dynamics of Peach Replant Tolerant and Susceptible Rootstocks in Soilswith Different Cropping History

Atucha¹

2017

J Hortic

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Root Dynamics of Peach Replant Tolerant and Susceptible Rootstocks in Soilswith Different Cropping History

Atucha¹

2017

J Hortic

View full text Add to dashboard Cite

“…For reference, the sycamore maple and E. coli LMCO proteins migrate with apparent molecular masses of 97.4 and 54 kDa, respectively, in denaturing SDS-PAGE gels [20,34]. 29 [27][28][29][30][31][32][33] must have been retained in an intracellular compartment of the transgenic tobacco cells. If this intracellular localization results in a Ltlacc2.2 enzyme having little or no glycosylation, it could help explain the observation that in SDS-PAGE gels the Ltlacc2.2 enzyme had a migration rate closer to the E. coli yacK MCO than the Aplacc1.1 enzyme (Fig.…”

Section: Discussionmentioning

confidence: 99%

“…Sequence alignment and modeling of the Ltlacc2.2 LMCO identified a region of the protein that may be influential in conferring ferroxidase activity to these enzymes [27][28][29][30][31][32][33] ( Fig. 3).…”

Section: Jt Hoopes Jfd Dean / Plant Physiology and Biochemistrymentioning

confidence: 99%

“…Following the traditions of enzyme nomenclature, more descriptive names may be assigned once specific catalytic reactions and metabolic functions are defined for the various LMCOs. LMCOs have been identified in bacteria, fungi and animals [28], where they function in metal oxidation [6,7,20] and lignin degradation [12], as well as detoxification of antimicrobial agents [27]. Additional LMCOs have been cloned and characterized from several plant species [19,22,23,32], yet their physiological functions in these organisms remain unclear [5].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of Laccase-like Multicopper Oxidases (LMCOs) in Arabidopsis thaliana

Dean¹

2008

View full text Add to dashboard Cite

Significant Findings:1. The At2g30210 LMCO harbors strong phenoloxidase activity, but no detectable ferroxidase or other metal oxidase activity. At the time the original proposal was submitted we had demonstrated expression of the At2g30210 protein to high levels in E. coli. However, we were not able to recover active enzyme, nor were we able to reconstitute activity in the heterologously expressed protein using protocols developed for metal-replacement studies of Rhus vernicifera laccase, the archetype LMCO. We subsequently prepared appropriate constructs for expression of the gene in plant cells, and isolated several lines of transgenic tobacco (BY2) cells that produced measurable amounts of active phenoloxidase. None of the cell lines produced large quantities of the enzyme or secreted freely soluble enzyme to the medium. After considerable effort, we were able to recover cellular extracts several tens of micrograms of partially purified enzyme that were tested using multiple assays for phenoloxidase, as well as ferroxidase and metal oxidase, activities. Although the enzyme proved highly active as a phenoloxidase ( Fig. 1), no ferroxidase, copper oxidase or manganese oxidase activity was detected, even when the enzyme was added to the assays in great excess over the positive controls. Although the remote possibility remains that the At2g30210 LMCO might be able to oxidize metal ion substrates if properly assisted by unknown ancillary proteins, the simplest explanation of our results is that the enzyme is primarily a phenoloxidase and carries out its physiological function(s) in Arabidopsis via this activity. coli LMCO, CueO, harboring an equivalent level of phenoloxidase activity (Lane cueO) provided a positive control for ferroxidase activity. Cleared zones representing ferroxidase activity were visualized by applying the ferrous ion chelator, 3-(2-pyridyl)-5,6-bis (4-phenylsulfonic acid)-1,2,4-triazine (ferrozine). At LMCOcueO At LMCO 2. T-DNA knockouts of At2g30210 show reduced growth, altered root morphology, and a response to sucrose. Among the most useful resources available for the study of Arabidopsis genes are the collections of T-DNA insert lines developed and cataloged at the Salk Institute and the gene-trap lines developed at Cold Spring Harbor Laboratory. A line was identified in the Salk collection as having an insert in the last intron of the At2g30210 gene. Upon obtaining a homozygous line for the insert, we found the mutation to be leaky, ostensibly because the T-DNA was spliced out of mature transcripts at a low, but sufficient, frequency for phenotypic escape. However, levels of mature transcript were always less than 30% of levels seen in wild-type Arabidopsis. In the course of working with the Salk T-DNA line, a second insertion mutant was identified among the gene-trap lines produced at CSHL (GT7855). This insertion was in the second exon of the gene, where it resulted in a "strong" allele from which no mature transcripts for At2g30210 could be detected in homozygous lines. Both knockout...

show abstract

“…At the initial stage of pathogenesis L. maculans is a necrotroph and it benefits from the overproduction of ROS, which are toxic to the plant cellular structures, including the photosynthetic apparatus (Mayer et al 2001). In our previous work we described the changes in the activity of the photosynthetic apparatus and chlorophyll content in the cotyledons of winter rape growing on an agar medium containing a toxic culture of L. maculans / L. biglobosa filtrates (Hura et al 2014b, c).…”

Section: Introductionmentioning

confidence: 99%

Carbohydrate, phenolic and antioxidant level in relation to chlorophyll a content in oilseed winter rape (Brassica napus L.) inoculated with Leptosphaeria maculans

Hura

Dziurka

et al. 2015

Eur J Plant Pathol

View full text Add to dashboard Cite

The relationships between the level of chlorophyll a, and the content of soluble carbohydrates, phenolics and low molecular antioxidants in the leaves of three oilseed winter rape varieties with different resistance to Leptosphaeria maculans were determined. During pathogenesis, an increase in the content of chlorophyll a in the resistant and medium-sensitive rape varieties was observed. In these varieties, the level of chlorophyll a significantly correlated with the content of primary metabolites in the form of soluble sugars, as well as with the level of free and cell wall-bound phenolics, and lowmolecular antioxidants. In contrast, a decrease in soluble carbohydrates, observed during the pathogenesis in the susceptible variety, was accompanied by lower level of chlorophyll a and with high activity of reactive oxygen species. Significant correlations were also confirmed for the cell wall-bound phenolics and water content in the leaves of the resistant and medium-sensitive variety.

show abstract

Mechanisms of survival of necrotrophic fungal plant pathogens in hosts expressing the hypersensitive response

Cited by 173 publications

References 60 publications

Root Dynamics of Peach Replant Tolerant and Susceptible Rootstocks in Soilswith Different Cropping History

Root Dynamics of Peach Replant Tolerant and Susceptible Rootstocks in Soilswith Different Cropping History

Characterization of Laccase-like Multicopper Oxidases (LMCOs) in Arabidopsis thaliana

Carbohydrate, phenolic and antioxidant level in relation to chlorophyll a content in oilseed winter rape (Brassica napus L.) inoculated with Leptosphaeria maculans

Contact Info

Product

Resources

About