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Peter Roessingh - One of the best experts on this subject based on the ideXlab platform.
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Olfactory receptors on the maxillary palps of small ermine moth larvae: evolutionary history of benzaldehyde sensitivity
Journal of Comparative Physiology A, 2007Co-Authors: Peter Roessingh, Steph B. J. MenkenAbstract:In lepidopterous larvae the maxillary palps contain a large portion of the sensory equipment of the insect. Yet, knowledge about the sensitivity of these cells is limited. In this paper a morphological, behavioral, and electrophysiological investigation of the maxillary palps of Yponomeuta cagnagellus (Lepidoptera: Yponomeutidae) is presented. In addition to thermoreceptors, CO_2 receptors, and gustatory receptors, evidence is reported for the existence of two groups of receptor cells sensitive to plant volatiles. Cells that are mainly sensitive to ( E )-2-hexenal and hexanal or to ( Z )-3-hexen-1-ol and 1-hexanol were found. Interestingly, a high sensitivity for benzaldehyde was also found. This compound is not known to be present in Euonymus Europaeus , the host plant of the monophagous Yponomeuta cagnagellus , but it is a prominent compound in Rosaceae, the presumed hosts of the ancestors of Y. cagnagellus . To elucidate the evolutionary history of this sensitivity, and its possible role in host shifts, feeding responses of three Yponomeuta species to benzaldehyde were investigated. The results confirm the hypothesis that the sensitivity to benzaldehyde evolved during the ancestral shift from Celastraceae to Rosaceae and can be considered an evolutionary relict, retained in the recently backshifted Celastraceae-specialist Y. cagnagellus .
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Host acceptance behaviour of the small ermine moth Yponomeuta cagnagellus: larvae and adults use different stimuli.
Chemoecology, 2000Co-Authors: Peter Roessingh, Katja H. Hora, S. Ying Fung, Anja Peltenburg, Steph B. J. MenkenAbstract:The sugar alcohol dulcitol is a strong feeding stimulant for larvae of the small ermine moth Yponomeuta cagnagellus. In this paper we tested the hypothesis that dulcitol also acts as an oviposition stimulant for this species. We found that the sugar-alcohol dulcitol was present on the surface of the host Euonymus Europaeus. We also showed that (as yet unidentified compounds) can be systemically transferred (i.e. by uptake and transport via the vascular system) from E. Europaeus, to the non-host Crataegus monogyna and stimulate oviposition. However, no evidence was found that this stimulatory activity was due to dulcitol. Systemic enrichment of C. monogyna with dulcitol did not induce oviposition on this plant. Neither was the application of pure dulcitol on artificial twigs effective. In addition it was shown that when dulcitol was removed from host plant extracts, oviposition stimulatory activity was retained in the fraction without dulcitol. Synergism between dulcitol and other stimulants could not be demonstrated, however, high concentrations of dulcitol in combination with the main stimulant(s) showed a trend towards enhanced oviposition. It is concluded that the sugar alcohol dulcitol can only play a limited role in adult host acceptance behaviour. The hypothesis that a host shift in the genus Yponomeuta from Celastraceae to Rosaceae might have been facilitated by the presence of small amounts of dulcitol in Rosaceae therefore needs to be restricted to larval feeding behaviour.
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Oviposition in Yponomeuta cagnagellus: the importance of contact cues for host plant acceptance
Physiological Entomology, 1999Co-Authors: K.h. Hora, Peter RoessinghAbstract:Summary Small ermine moths (Yponomeutidae: Lepidoptera) are specialist herbivores. Species within the genus Yponomeuta are each specialized on a limited number of plant species, mainly within genera belonging to the Celastraceae. European Yponomeuta species have developed new specialized host affiliations, mainly on rosaceous hosts. Since these host shifts are reputed to be of consequence for speciation, the role of the ovipositing female is of particular interest. Study of the pre-oviposition behaviour of gravid Y. cagnagellus (Hb.) moths on host (Euonymus Europaeus), non-host (Crateagus monogyna) and artificial oviposition substrates, provided information on the nature of the cues used for host plant acceptance and the insect’s perception of these cues. Host selection by adult females occurs with contact chemoreceptors probably located on the antennae or tarsi. MeOH-soluble, non-volatile phytochemical compounds washed from the host plant’s surface and applied on an artificial twig are sufficient to stimulate a complete sequence of behavioural elements leading to oviposition. Volatiles do not have a large effect on the pre-oviposition behaviour.
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A Novel Bioassay for Yponomeuta cagnagellus Oviposition in Response to Extracts of Host and Nonhost Plant Surface Compounds
Journal of Chemical Ecology, 1999Co-Authors: K.h. Hora, Peter RoessinghAbstract:Yponomeuta cagnagellus is a phytophagous moth species specialized on Euonymus Europaeus. Host discrimination by the adult female is an important aspect of host specialization and is based mainly on the distinctive secondary chemistry of host and nonhosts. This paper describes a bioassay that was developed to study the effect of isolated plant surface compounds on Yponomeuta oviposition. Adult moths recognize their hosts through chemical stimuli on the leaf or twig surface. Relatively apolar compounds extracted from the host twig surface by washing in dichlormethane do not stimulate oviposition. More polar, methanol-soluble compounds do, and this stimulation is dose dependent. Moths are able to recognize hosts solely by their surface compounds: females show a strong preference for artificial twigs treated with methanolic extracts of their hosts compared to those treated with methanolic extracts of nonhosts Crataegus monogyna and Prunus spinosa (both of which are hosts for closely related Y. padellus). Shape and surface characteristics of the oviposition substrate also influence oviposition. The substrate needs to resemble the basic form of a twig (i.e., cylindrical), and females prefer a coarse surface with irregularities over a smooth one.
Willy J Peumans - One of the best experts on this subject based on the ideXlab platform.
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The “Old” Euonymus Europaeus Agglutinin Represents a Novel Family of Ubiquitous Plant Proteins
Plant Physiology, 2008Co-Authors: Elke Fouquaert, Willy J Peumans, Savvas N. Savvides, Paul Proost, David F Smith, Els J. M. Van DammeAbstract:Molecular cloning of the “old” but still unclassified Euonymus Europaeus agglutinin (EEA) demonstrated that the lectin is a homodimeric protein composed of 152 residue subunits. Analysis of the deduced sequence indicated that EEA is synthesized without a signal peptide and undergoes no posttranslational processing apart from the removal of a six-residue N-terminal peptide. Glycan array screening confirmed the previously reported high reactivity of EEA toward blood group B oligosaccharides but also revealed binding to high mannose N-glycans, providing firm evidence for the occurrence of a plant carbohydrate-binding domain that can interact with structurally different glycans. Basic Local Alignment Search Tool searches indicated that EEA shares no detectable sequence similarity with any other lectin but is closely related evolutionarily to a domain that was first identified in some abscisic acid- and salt stress-responsive rice (Oryza sativa) proteins, and, according to the available sequence data, might be ubiquitous in Spermatophyta. Hence, EEA can be considered the prototype of a novel family of presumably cytoplasmic/nuclear proteins that are apparently ubiquitous in plants. Taking into account that some of these proteins are definitely stress related, the present identification of the EEA lectin domain might be a first step in the recognition of the involvement and importance of protein-glycoconjugate interactions in some essential cellular processes in Embryophyta.
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Synergistic antifungal activity of two chitin-binding proteins from spindle tree (Euonymus Europaeus L.)
Planta, 2004Co-Authors: Karolien P. B. Bergh, Willy J Peumans, Paul Proost, Jozef Coosemans, Pierre Rougé, Tanya Krouglova, Yves Engelborghs, Els J. M. Van DammeAbstract:Two structurally different chitin-binding proteins were isolated from bark and leaves of the spindle tree ( Euonymus Europaeus L.). Both the small hevein-like chitin-binding protein (Ee-CBP) and the classical class-I chitinase (Ee-chitinase) possess antifungal properties, Ee-CBP being far more potent than Ee-chitinase. In addition, Ee-CBP and Ee-chitinase display a pronounced synergistic effect when added together in the test medium. Determination of the biological activities indicates that the synergism between Ee-CBP and Ee-chitinase relies on a different mode of action. Cloning and sequencing of the corresponding genes further revealed that Ee-CBP and Ee-chitinase are simultaneously expressed in bark and leaf tissues, and hence can act synergistically in planta . Moreover, analysis of the deduced sequences allowed the exact relationship between the structurally different Ee-CBP and Ee-chitinase to be corroborated. Both proteins are synthesized as similar chimeric precursors consisting of an N-terminal hevein domain linked to a C-terminal chitinase-like domain by a hinge region. However, whereas in the case of Ee-chitinase the C-terminal chitinase domain remains linked to the N-terminal hevein domain, the corresponding domain is cleaved from the Ee-CBP-precursor resulting in the formation of the hevein-type Ee-CBP. Since both precursors are—apart from the hinge region between the hevein and chitinase domains—very similar, the Ee-CBP/Ee-chitinase system offers a unique opportunity to study the importance of sequence and/or structural information comprised in the hinge region for the posttranslational processing of the respective precursor proteins.
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five disulfide bridges stabilize a hevein type antimicrobial peptide from the bark of spindle tree Euonymus Europaeus l
FEBS Letters, 2002Co-Authors: Karolien Van Den Bergh, Paul Proost, Jo Van Damme, Jozef Coosemans, Els J M Van Damme, Willy J PeumansAbstract:A small 45 amino acid residue antifungal polypeptide was isolated from the bark of spindle tree (Euonymus Europaeus L.). Though the primary structure of this so-called E. Europaeus chitin-binding protein or Ee-CBP is highly similar to the hevein domain, it distinguishes itself from most previously identified hevein-type antimicrobial peptides (AMP) by the presence of two extra cysteine residues that form an extra disulfide bond. Due to these five disulfide bonds Ee-CBP is a remarkably stable protein. Agar diffusion and microtiterplate assays demonstrated that Ee-CBP is a potent antimicrobial protein. IC50-values as low as 1 μg/ml were observed for the fungus Botrytis cinerea. Comparative assays further demonstrated that Ee-CBP is a stronger inhibitor of fungal growth than Ac-AMP2 from Amaranthus caudatus seeds, which is considered one of the most potent antifungal hevein-type plant proteins.
D. Schlüter - One of the best experts on this subject based on the ideXlab platform.
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Wie werden Wachstumsparameter von Gehölzen auf unterschiedlichen Standorten durch das Verschulen beeinflusst?
Erwerbs-Obstbau, 2005Co-Authors: Heike Bohne, Andrea Bremer, Bettina Baldin, D. SchlüterAbstract:Auf drei Standorten, die sich hinsichtlich Klima- und Bodeneigenschaften unterscheiden, wurde für die Kulturen Carpinus betulus , Quercus robur , Euonymus Europaeus am Ende des zweiten Standjahres untersucht, wie sich das Verschulen auf das Längen- und Dickenwachstum des Sprosses, auf die Sortierung und auf das Wurzelwachstum ausgewirkt hat. Das Pflanzenwachstum wurde zusätzlich durch das Spross-Wurzel-Verhältnis, das Verhältnis Trieblänge zu Wurzelhalsdurchmesser und Anteile an Grob- und Feinwurzeln charakterisiert. Die Bedeutung der Wachstumsparameter als Kriterium für den Anwachserfolg und die Überlebensrate wird diskutiert. Das Verschulen hat das Sprosswachstum stärker als das Wurzelwachstum beeinflusst. Es bestehen große Wachstumsunterschiede zwischen den Standorten. Das Verschulen hat sich auf dem Standort mit den besten Bedingungen für die Wasser- und N-Versorgung der Kulturen am stärksten positiv auf das Sprosswachstum ausgewirkt. Auf dem Standort mit der schlechtesten Wasserversorgung blieb ein Effekt des Verschulens auf die Sortierung aus. The influence of transplanting on height, root neck diameter, and grading was investigated for Carpinus betulus , Quercus robur , and Euonymus Europaeus on three sites with different climate and soil properties. Additionally, plant growth was characterized by the shoot-to-root ratio, height-to-root neck diameter, and proportions of coarse and fine roots. The significance of the growth parameters as criteria for survival is discussed. Transplanting influenced shoot growth more than root growth. The growth of the plants was highly site-dependent. Transplanting increased growth most on the site with the best conditions for water and N supply. Transplanting had no effect on grading for the site with the worst water supply.
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Wie werden Wachstumsparameter von Gehölzen auf unterschiedlichen Standorten durch das Verschulen beeinflusst
Erwerbs-Obstbau, 2005Co-Authors: Heike Bohne, Andrea Bremer, Bettina Baldin, D. SchlüterAbstract:Auf drei Standorten, die sich hinsichtlich Klima- und Bodeneigenschaften unterscheiden, wurde fur die Kulturen Carpinus betulus, Quercus robur, Euonymus Europaeus am Ende des zweiten Standjahres untersucht, wie sich das Verschulen auf das Langen- und Dickenwachstum des Sprosses, auf die Sortierung und auf das Wurzelwachstum ausgewirkt hat. Das Pflanzenwachstum wurde zusatzlich durch das Spross-Wurzel-Verhaltnis, das Verhaltnis Trieblange zu Wurzelhalsdurchmesser und Anteile an Grob- und Feinwurzeln charakterisiert. Die Bedeutung der Wachstumsparameter als Kriterium fur den Anwachserfolg und die Uberlebensrate wird diskutiert.
Paul Proost - One of the best experts on this subject based on the ideXlab platform.
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Lectin activity of the nucleocytoplasmic EUL protein from Arabidopsis thaliana.
Biochemical and biophysical research communications, 2011Co-Authors: Jonas Van Hove, Paul Proost, David F Smith, Elke Fouquaert, Els J M Van DammeAbstract:The Euonymus lectin (EUL) domain was recognized as the structural motif for a novel class of putative carbohydrate binding proteins. Confocal microscopy demonstrated that the lectin from Euonymus Europaeus (EEA) as well as the EUL protein from Arabidopsis thaliana (ArathEULS3) are located in the nucleocytoplasmic compartment of the plant cell. ArathEULS3 as well as its EUL domain were successfully expressed in Pichia pastoris and purified. The EUL domain from Arabidopsis interacts with glycan structures containing Lewis Y, Lewis X and lactosamine, indicating that it can be considered a true lectin domain. Despite the high sequence identity between the EUL domains in EEA and ArathEULS3, both domains recognize different carbohydrate structures.
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The “Old” Euonymus Europaeus Agglutinin Represents a Novel Family of Ubiquitous Plant Proteins
Plant Physiology, 2008Co-Authors: Elke Fouquaert, Willy J Peumans, Savvas N. Savvides, Paul Proost, David F Smith, Els J. M. Van DammeAbstract:Molecular cloning of the “old” but still unclassified Euonymus Europaeus agglutinin (EEA) demonstrated that the lectin is a homodimeric protein composed of 152 residue subunits. Analysis of the deduced sequence indicated that EEA is synthesized without a signal peptide and undergoes no posttranslational processing apart from the removal of a six-residue N-terminal peptide. Glycan array screening confirmed the previously reported high reactivity of EEA toward blood group B oligosaccharides but also revealed binding to high mannose N-glycans, providing firm evidence for the occurrence of a plant carbohydrate-binding domain that can interact with structurally different glycans. Basic Local Alignment Search Tool searches indicated that EEA shares no detectable sequence similarity with any other lectin but is closely related evolutionarily to a domain that was first identified in some abscisic acid- and salt stress-responsive rice (Oryza sativa) proteins, and, according to the available sequence data, might be ubiquitous in Spermatophyta. Hence, EEA can be considered the prototype of a novel family of presumably cytoplasmic/nuclear proteins that are apparently ubiquitous in plants. Taking into account that some of these proteins are definitely stress related, the present identification of the EEA lectin domain might be a first step in the recognition of the involvement and importance of protein-glycoconjugate interactions in some essential cellular processes in Embryophyta.
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Synergistic antifungal activity of two chitin-binding proteins from spindle tree (Euonymus Europaeus L.)
Planta, 2004Co-Authors: Karolien P. B. Bergh, Willy J Peumans, Paul Proost, Jozef Coosemans, Pierre Rougé, Tanya Krouglova, Yves Engelborghs, Els J. M. Van DammeAbstract:Two structurally different chitin-binding proteins were isolated from bark and leaves of the spindle tree ( Euonymus Europaeus L.). Both the small hevein-like chitin-binding protein (Ee-CBP) and the classical class-I chitinase (Ee-chitinase) possess antifungal properties, Ee-CBP being far more potent than Ee-chitinase. In addition, Ee-CBP and Ee-chitinase display a pronounced synergistic effect when added together in the test medium. Determination of the biological activities indicates that the synergism between Ee-CBP and Ee-chitinase relies on a different mode of action. Cloning and sequencing of the corresponding genes further revealed that Ee-CBP and Ee-chitinase are simultaneously expressed in bark and leaf tissues, and hence can act synergistically in planta . Moreover, analysis of the deduced sequences allowed the exact relationship between the structurally different Ee-CBP and Ee-chitinase to be corroborated. Both proteins are synthesized as similar chimeric precursors consisting of an N-terminal hevein domain linked to a C-terminal chitinase-like domain by a hinge region. However, whereas in the case of Ee-chitinase the C-terminal chitinase domain remains linked to the N-terminal hevein domain, the corresponding domain is cleaved from the Ee-CBP-precursor resulting in the formation of the hevein-type Ee-CBP. Since both precursors are—apart from the hinge region between the hevein and chitinase domains—very similar, the Ee-CBP/Ee-chitinase system offers a unique opportunity to study the importance of sequence and/or structural information comprised in the hinge region for the posttranslational processing of the respective precursor proteins.
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five disulfide bridges stabilize a hevein type antimicrobial peptide from the bark of spindle tree Euonymus Europaeus l
FEBS Letters, 2002Co-Authors: Karolien Van Den Bergh, Paul Proost, Jo Van Damme, Jozef Coosemans, Els J M Van Damme, Willy J PeumansAbstract:A small 45 amino acid residue antifungal polypeptide was isolated from the bark of spindle tree (Euonymus Europaeus L.). Though the primary structure of this so-called E. Europaeus chitin-binding protein or Ee-CBP is highly similar to the hevein domain, it distinguishes itself from most previously identified hevein-type antimicrobial peptides (AMP) by the presence of two extra cysteine residues that form an extra disulfide bond. Due to these five disulfide bonds Ee-CBP is a remarkably stable protein. Agar diffusion and microtiterplate assays demonstrated that Ee-CBP is a potent antimicrobial protein. IC50-values as low as 1 μg/ml were observed for the fungus Botrytis cinerea. Comparative assays further demonstrated that Ee-CBP is a stronger inhibitor of fungal growth than Ac-AMP2 from Amaranthus caudatus seeds, which is considered one of the most potent antifungal hevein-type plant proteins.
Heike Bohne - One of the best experts on this subject based on the ideXlab platform.
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Wie werden Wachstumsparameter von Gehölzen auf unterschiedlichen Standorten durch das Verschulen beeinflusst?
Erwerbs-Obstbau, 2005Co-Authors: Heike Bohne, Andrea Bremer, Bettina Baldin, D. SchlüterAbstract:Auf drei Standorten, die sich hinsichtlich Klima- und Bodeneigenschaften unterscheiden, wurde für die Kulturen Carpinus betulus , Quercus robur , Euonymus Europaeus am Ende des zweiten Standjahres untersucht, wie sich das Verschulen auf das Längen- und Dickenwachstum des Sprosses, auf die Sortierung und auf das Wurzelwachstum ausgewirkt hat. Das Pflanzenwachstum wurde zusätzlich durch das Spross-Wurzel-Verhältnis, das Verhältnis Trieblänge zu Wurzelhalsdurchmesser und Anteile an Grob- und Feinwurzeln charakterisiert. Die Bedeutung der Wachstumsparameter als Kriterium für den Anwachserfolg und die Überlebensrate wird diskutiert. Das Verschulen hat das Sprosswachstum stärker als das Wurzelwachstum beeinflusst. Es bestehen große Wachstumsunterschiede zwischen den Standorten. Das Verschulen hat sich auf dem Standort mit den besten Bedingungen für die Wasser- und N-Versorgung der Kulturen am stärksten positiv auf das Sprosswachstum ausgewirkt. Auf dem Standort mit der schlechtesten Wasserversorgung blieb ein Effekt des Verschulens auf die Sortierung aus. The influence of transplanting on height, root neck diameter, and grading was investigated for Carpinus betulus , Quercus robur , and Euonymus Europaeus on three sites with different climate and soil properties. Additionally, plant growth was characterized by the shoot-to-root ratio, height-to-root neck diameter, and proportions of coarse and fine roots. The significance of the growth parameters as criteria for survival is discussed. Transplanting influenced shoot growth more than root growth. The growth of the plants was highly site-dependent. Transplanting increased growth most on the site with the best conditions for water and N supply. Transplanting had no effect on grading for the site with the worst water supply.
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Wie werden Wachstumsparameter von Gehölzen auf unterschiedlichen Standorten durch das Verschulen beeinflusst
Erwerbs-Obstbau, 2005Co-Authors: Heike Bohne, Andrea Bremer, Bettina Baldin, D. SchlüterAbstract:Auf drei Standorten, die sich hinsichtlich Klima- und Bodeneigenschaften unterscheiden, wurde fur die Kulturen Carpinus betulus, Quercus robur, Euonymus Europaeus am Ende des zweiten Standjahres untersucht, wie sich das Verschulen auf das Langen- und Dickenwachstum des Sprosses, auf die Sortierung und auf das Wurzelwachstum ausgewirkt hat. Das Pflanzenwachstum wurde zusatzlich durch das Spross-Wurzel-Verhaltnis, das Verhaltnis Trieblange zu Wurzelhalsdurchmesser und Anteile an Grob- und Feinwurzeln charakterisiert. Die Bedeutung der Wachstumsparameter als Kriterium fur den Anwachserfolg und die Uberlebensrate wird diskutiert.
