Molecular Basis of Plant Defense Responses to Fungal Infections

Hahlbrock, Klaus; Groß, Petra; Colling, Christiane; Scheel, Dierk

doi:10.1007/978-1-4615-3304-7_15

Cited by 3 publications

(2 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our experiments confirmed that larvae of the colorado beetle can feed on tomato leaves. Plants may acquire resistance to fungi or even insects [8,26], although the time-consuming selection or breeding processes cannot be readily applied to plants of agricultural importance. The transfer of a resistance gene into tomato plants is therefore a direct way in plant protection against Coleoptera.…”

Section: Discussionmentioning

confidence: 99%

Development of insect resistance in tomato plants expressing the δ-endotoxin gene ofBacillus thuringiensis subsp.tenebrionis

et al. 1995

View full text Add to dashboard Cite

A crystal ~-endotoxin gene of Bacillus thuringiensis subsp, tenebrionis (B.t.t.) encoding a coleopteran insect-specific toxin was used to construct a chimeric gene which expressed the toxin in plant cells. Via an Agrobacterium tumefaciens binary vector system, the toxin gene was transferred into tomato cells. From leaf disks recombinant plants were regenerated. Hybridization experiments demonstrated that these plants synthesized toxin-specific mRNA of the expected size. Transgenic tomato plants with the chimeric B.t.t. toxin gene contained a 74 kDa protein which cross-reacted with toxin antibodies. The expression caused a significant insecticidal activity of the transgenic tomato plants against Colorado potato beetle larvae.

show abstract

Section: Discussionmentioning

confidence: 99%

Development of insect resistance in tomato plants expressing the δ-endotoxin gene ofBacillus thuringiensis subsp.tenebrionis

et al. 1995

View full text Add to dashboard Cite

show abstract

“…Most microorganisms are unsuccessful in establishing themselves as plant parasites due to defense mechanisms controlled by the host during the invasion process. These mechanisms are stimulated by molecules of microorganism origin, generically termed elicitors (Dixon & Lamb, 1990;Hahlbrock et al, 1990), which induce reaction cascades usually resulting in a necrotic hypersensitive response within the host cell (Anderson et al, 1991). Elicitins are both a novel class of protein elicitors and an original family of proteins secreted by the phytopathogenic fungi belonging to the genus Phytophthora (Pernollet et al, 1993).…”

mentioning

confidence: 99%

1H and 15N Resonance Assignment and Secondary Structure of Capsicein, an .alpha.-Elicitin, Determined by Three-Dimensional Heteronuclear NMR

Bouaziz¹,

Heijenoort²,

Huet³

et al. 1994

Biochemistry

View full text Add to dashboard Cite

The backbone 1H and 15N resonance assignments and solution secondary structure determination of capsicein, a protein of 98 residues with a molecular mass of 10161 Da, are presented. Capsicein belongs to the elicitin family, elicitor molecules having toxic and signaling properties that are secreted by Phytophthora fungi, responsible for the incompatible hypersensitive reaction of diverse plant species leading to resistance against fungal or bacterial plant pathogens. The protein was uniformly labeled with 15N to overcome spectral overlap of the proton resonances. A combination of 3D HOHAHA-HMQC and 3D NOESY-HMOC experiments allowed the identification of spin systems with through-bond correlations, which were in turn correlated by through-space connections. The sequential assignment was obtained for main- and side-chain resonances and led to the identification of all secondary structures. A 3D HMQC-NOESY-HMQC experiment was performed which characterized the NH(i)-NH(i+1) connections specific to alpha-helical structures. This proved particularly useful for the assignment of degenerate amide protons of successive residues in alpha-helical structures. The data show five alpha-helical regions comprising residues 5-18, 26-33, 44-58, 59-67, and 86-98 and a two-stranded antiparallel beta-sheet involving residues 70-75 and 80-85, packed around a hydrophobic core grouping all of the aromatic residues. The C-terminal secondary structure motifs of capsicein evoke phospholipase structural features, which suggests that elicitins might interact with the lipidic molecules of the plasma membrane.

show abstract

Mapping the Elicitor and Necrotic Sites of Phytophthora Elicitins with Synthetic Peptides and Reporter Genes Controlled by Tobacco Defense Gene Promoters

Pérez

Huet²,

Nespoulous³

et al. 1997

MPMI

View full text Add to dashboard Cite

Elicitins are 10-kDa proteins secreted by Phytophthora and Pythium fungi that elicit a hypersensitive-like necrotic reaction, leading to resistance against fungal and bacterial plant pathogens. Induction of necrosis and resistance were previously shown to be borne by different sites of the molecule. Furthermore, sequence comparison indicated several potential residues necessary for necrosis. The role of one of these residues was previously evidenced with site-directed mutagenesis. In order to locate other necrosis-determining sites and reveal the defense-eliciting sites, we synthesized a series of synthetic peptides. Tests were performed on two types of transgenic tobacco plants, both transformed with a construction containing the beta-glucuronidase reporter gene, in one case controlled by the promoter of the multiple stimulus response gene str 246C and in the other by the promoter of the pathogenesis-related gene PR1a. We report that only certain peptides were found to be active. Whereas PR1a induction was consistently correlated with induction of necrosis, four peptides were observed to induce only str 246C expression without necrosis, which led to differentiate the defense-eliciting sites from the necrotic sites. From the structure-function relationship thus obtained, two different defense pathways were inferred to be independently induced by elicitins.

show abstract

Molecular Basis of Plant Defense Responses to Fungal Infections

Cited by 3 publications

References 10 publications

Development of insect resistance in tomato plants expressing the δ-endotoxin gene ofBacillus thuringiensis subsp.tenebrionis

Development of insect resistance in tomato plants expressing the δ-endotoxin gene ofBacillus thuringiensis subsp.tenebrionis

1H and 15N Resonance Assignment and Secondary Structure of Capsicein, an .alpha.-Elicitin, Determined by Three-Dimensional Heteronuclear NMR

Mapping the Elicitor and Necrotic Sites of Phytophthora Elicitins with Synthetic Peptides and Reporter Genes Controlled by Tobacco Defense Gene Promoters

Contact Info

Product

Resources

About