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Claire Périlleux - One of the best experts on this subject based on the ideXlab platform.

  • vernalization induced repression of flowering locus c stimulates flowering in Sinapis alba and enhances plant responsiveness to photoperiod
    New Phytologist, 2008
    Co-Authors: Maria Daloia, Pierre Tocquin, Claire Périlleux
    Abstract:

    Summary • Of the Brassicaceae, Sinapis alba has been intensively studied as a physiological model of induction of flowering by a single long day (LD), while molecular-genetic analyses of Arabidopsis thaliana have disclosed complex interactions between pathways controlling flowering in response to different environmental cues, such as photoperiod and vernalization. The vernalization process in S. alba was therefore analysed here. • The coding sequence of S. alba SaFLC, which is orthologous to the A. thaliana floral repressor FLOWERING LOCUS C, was isolated and the transcript levels quantified in different conditions. • Two-week-old seedlings grown in noninductive short days (SDs) were vernalized for 1–6 wk. Down-regulation of SaFLC was already marked after 1 wk of cold but 2 wk was needed for a significant acceleration of flowering. Flower buds were initiated during vernalization. When vernalization was stopped after 1 wk, repression of SaFLC was not stable but a significant increase in plant responsiveness to 16-h LDs was observed when LDs followed immediately after the cold treatment. • These results suggest that vernalization does not only work when plants experience long exposure to cold during the winter: shorter cold periods might stimulate flowering of LD plants if they occur when photoperiod is increasing, such as in spring.

  • Gibberellins and the floral transition in Sinapis alba
    Physiologia Plantarum, 2004
    Co-Authors: Laurent Corbesier, Gaelle Kustermans, Claire Périlleux, Siegbert Melzer, Thomas Moritz, Andrée Havelange, Georges Bernier
    Abstract:

    The putative role of gibberellins in the transition to flowering was investigated in Sinapis alba, a caulescent long-day (LD) plant. It was observed that: (1) physiological doses of exogenous gibberellins (GA 1 , GA 3 , GA 9 ) do not cause the floral shift of the meristem when applied to plants grown in short days but have some positive effect on the flowering response to a suboptimal LD; no inhibition was observed in any case; (2) GA-biosynthesis inhibitors (prohexadione-Ca and paclobutrazol) considerably inhibit stem growth but have some negative effect on flowering only when a suboptimal LD is given; and (3) the floral transition induced by one 22-h LD does not correlate with any detectable change in GA content of the apical bud, of the leaves, and of the phloem exudate reaching the apex. Taken together, these results suggest that GAs do not act as a major signal for photoperiodic flower induction in Sinapis.

  • c n ratio increases in the phloem sap during floral transition of the long day plants Sinapis alba and arabidopsis thaliana
    Plant and Cell Physiology, 2002
    Co-Authors: Laurent Corbesier, Georges Bernier, Claire Périlleux
    Abstract:

    ;In plants of Sinapis alba and Arabidopsis thaliana, leaf exudate (phloem sap) was analysed during and after a single long day inducing flowering and in control short days. The amounts of carbohydrates and amino acids were measured to estimate the organic C : N ratio. In both species, the C : N ratio of the phloem sap increased markedly and early during the inductive treatment, suggesting that an inequality in organic C and N supply to the apical meristem may be important at floral transition.

  • n content of phloem and xylem exudates during the transition to flowering in Sinapis alba and arabidopsis thaliana
    Plant Cell and Environment, 2001
    Co-Authors: Laurent Corbesier, Pierre Lejeune, Georges Bernier, Andrée Havelange, Claire Périlleux
    Abstract:

    The involvement of nitrogenous substances in the transition to flowering was investigated in Sinapis alba and Arabidopsis thaliana (Columbia). Both species grown in short days (SD) are induced to flower by one long day (LD). In S. alba, the phloem sap (leaf and apical exudates) and the xylem sap (root exudate) were analysed in LD versus SD. In A. thaliana, only the leaf exudate could be analysed but an alternative system for inducing flowering without day-length extension was used: the displaced SD (DSD). Significant results are: (i) in both species, the leaf exudate was enriched in Gln during the inductive LD, at a time compatible with export of the floral stimulus; (ii) in S. alba, the root export of amino acids decreased in LD, whereas the nitrate remained unchanged – thus the extra-Gln found in the leaf exudate should originate from the leaves; (iii) extra-Gln was also found very early in the apical exudate of S. alba in LD, together with more Glu; (iv) in A. thaliana induced by one DSD, the leaf export of Asn increased sharply, instead of Gln in LD. This agrees with Asn prevalence in C-limited plants. The putative role of amino acids in the transition to flowering is discussed.

Georges Bernier - One of the best experts on this subject based on the ideXlab platform.

  • Gibberellins and the floral transition in Sinapis alba
    Physiologia Plantarum, 2004
    Co-Authors: Laurent Corbesier, Gaelle Kustermans, Claire Périlleux, Siegbert Melzer, Thomas Moritz, Andrée Havelange, Georges Bernier
    Abstract:

    The putative role of gibberellins in the transition to flowering was investigated in Sinapis alba, a caulescent long-day (LD) plant. It was observed that: (1) physiological doses of exogenous gibberellins (GA 1 , GA 3 , GA 9 ) do not cause the floral shift of the meristem when applied to plants grown in short days but have some positive effect on the flowering response to a suboptimal LD; no inhibition was observed in any case; (2) GA-biosynthesis inhibitors (prohexadione-Ca and paclobutrazol) considerably inhibit stem growth but have some negative effect on flowering only when a suboptimal LD is given; and (3) the floral transition induced by one 22-h LD does not correlate with any detectable change in GA content of the apical bud, of the leaves, and of the phloem exudate reaching the apex. Taken together, these results suggest that GAs do not act as a major signal for photoperiodic flower induction in Sinapis.

  • c n ratio increases in the phloem sap during floral transition of the long day plants Sinapis alba and arabidopsis thaliana
    Plant and Cell Physiology, 2002
    Co-Authors: Laurent Corbesier, Georges Bernier, Claire Périlleux
    Abstract:

    ;In plants of Sinapis alba and Arabidopsis thaliana, leaf exudate (phloem sap) was analysed during and after a single long day inducing flowering and in control short days. The amounts of carbohydrates and amino acids were measured to estimate the organic C : N ratio. In both species, the C : N ratio of the phloem sap increased markedly and early during the inductive treatment, suggesting that an inequality in organic C and N supply to the apical meristem may be important at floral transition.

  • in situ localisation of cytokinins in the shoot apical meristem of Sinapis alba at floral transition
    Planta, 2002
    Co-Authors: Annie Jacqmard, Nathalie Detry, W Dewitte, Harry Van Onckelen, Georges Bernier
    Abstract:

    In plants of Sinapis alba L. induced to flower by one long day (LD), previous work showed that the phloem sap feeding the shoot apex is enriched in cytokinins of the isopentenyladenine (iP)-type between 9 and 25 h after start of the LD [P. Lejeune et al. (1994) Physiol Plant 90:522–528]. We have checked the hypothesis that the cytokinin content of the shoot apical meristem (SAM) should increase in response to floral induction by one LD using histoimmunolocalisation techniques and rabbit antiserum against isopentenyladenosine or zeatin riboside. The free bases iP and zeatin are present only in apical tissues containing dividing cells. At 30 h after the start of an inductive LD, a markedly increased iP immune reaction is observed in SAM tissues while the level of zeatin is not modified. Our results are in line with the data obtained by analysis of phloem sap.

  • n content of phloem and xylem exudates during the transition to flowering in Sinapis alba and arabidopsis thaliana
    Plant Cell and Environment, 2001
    Co-Authors: Laurent Corbesier, Pierre Lejeune, Georges Bernier, Andrée Havelange, Claire Périlleux
    Abstract:

    The involvement of nitrogenous substances in the transition to flowering was investigated in Sinapis alba and Arabidopsis thaliana (Columbia). Both species grown in short days (SD) are induced to flower by one long day (LD). In S. alba, the phloem sap (leaf and apical exudates) and the xylem sap (root exudate) were analysed in LD versus SD. In A. thaliana, only the leaf exudate could be analysed but an alternative system for inducing flowering without day-length extension was used: the displaced SD (DSD). Significant results are: (i) in both species, the leaf exudate was enriched in Gln during the inductive LD, at a time compatible with export of the floral stimulus; (ii) in S. alba, the root export of amino acids decreased in LD, whereas the nitrate remained unchanged – thus the extra-Gln found in the leaf exudate should originate from the leaves; (iii) extra-Gln was also found very early in the apical exudate of S. alba in LD, together with more Glu; (iv) in A. thaliana induced by one DSD, the leaf export of Asn increased sharply, instead of Gln in LD. This agrees with Asn prevalence in C-limited plants. The putative role of amino acids in the transition to flowering is discussed.

  • Putrescine export from leaves in relation to floral transition in Sinapis alba
    Physiologia Plantarum, 1996
    Co-Authors: Andrée Havelange, Pierre Lejeune, Georges Bernier, Ravindar Kaur-sawhney, Arthur W. Galston
    Abstract:

    Sinapis alba L. was induced to flower by either a long day or a displaced short day. Following collection of leaf (phloem) and root (xylem) exudates from induced and non-induced plants, polyamines in the exudates were extracted, separated and analyzed quantitatively. The titers of free and conjugated putrescine, the major polyamine fractions in all samples, increased early and markedly in leaf exudates during the floral transition, coinciding closely with movement of the floral stimulus out of the induced leaf. By contrast, putrescine titer in the root exudate did not increase. A spray of difluoromethylornithine (DFMO), an irreversible inhibitor of the putrescine-biosynthetic enzyme ornithine decarboxylase, at hour 8 of the long day considerably reduced the titer of free and conjugated putrescine in leaf exudates, and at the same time, markedly decreased the flowering response of induced plants. This effect of DFMO on flowering was substantially reversed by a simultaneous application of putrescine to the roots. DFMO sprayed on induced plants also suppressed early activation of indices of both mitosis and DNA synthesis in the shoot apical meristem. These results support the view that the extra putrescine synthesized in induced leaves is a necessary component of the floral stimulus in Sinapis.

Laurent Corbesier - One of the best experts on this subject based on the ideXlab platform.

  • Gibberellins and the floral transition in Sinapis alba
    Physiologia Plantarum, 2004
    Co-Authors: Laurent Corbesier, Gaelle Kustermans, Claire Périlleux, Siegbert Melzer, Thomas Moritz, Andrée Havelange, Georges Bernier
    Abstract:

    The putative role of gibberellins in the transition to flowering was investigated in Sinapis alba, a caulescent long-day (LD) plant. It was observed that: (1) physiological doses of exogenous gibberellins (GA 1 , GA 3 , GA 9 ) do not cause the floral shift of the meristem when applied to plants grown in short days but have some positive effect on the flowering response to a suboptimal LD; no inhibition was observed in any case; (2) GA-biosynthesis inhibitors (prohexadione-Ca and paclobutrazol) considerably inhibit stem growth but have some negative effect on flowering only when a suboptimal LD is given; and (3) the floral transition induced by one 22-h LD does not correlate with any detectable change in GA content of the apical bud, of the leaves, and of the phloem exudate reaching the apex. Taken together, these results suggest that GAs do not act as a major signal for photoperiodic flower induction in Sinapis.

  • c n ratio increases in the phloem sap during floral transition of the long day plants Sinapis alba and arabidopsis thaliana
    Plant and Cell Physiology, 2002
    Co-Authors: Laurent Corbesier, Georges Bernier, Claire Périlleux
    Abstract:

    ;In plants of Sinapis alba and Arabidopsis thaliana, leaf exudate (phloem sap) was analysed during and after a single long day inducing flowering and in control short days. The amounts of carbohydrates and amino acids were measured to estimate the organic C : N ratio. In both species, the C : N ratio of the phloem sap increased markedly and early during the inductive treatment, suggesting that an inequality in organic C and N supply to the apical meristem may be important at floral transition.

  • n content of phloem and xylem exudates during the transition to flowering in Sinapis alba and arabidopsis thaliana
    Plant Cell and Environment, 2001
    Co-Authors: Laurent Corbesier, Pierre Lejeune, Georges Bernier, Andrée Havelange, Claire Périlleux
    Abstract:

    The involvement of nitrogenous substances in the transition to flowering was investigated in Sinapis alba and Arabidopsis thaliana (Columbia). Both species grown in short days (SD) are induced to flower by one long day (LD). In S. alba, the phloem sap (leaf and apical exudates) and the xylem sap (root exudate) were analysed in LD versus SD. In A. thaliana, only the leaf exudate could be analysed but an alternative system for inducing flowering without day-length extension was used: the displaced SD (DSD). Significant results are: (i) in both species, the leaf exudate was enriched in Gln during the inductive LD, at a time compatible with export of the floral stimulus; (ii) in S. alba, the root export of amino acids decreased in LD, whereas the nitrate remained unchanged – thus the extra-Gln found in the leaf exudate should originate from the leaves; (iii) extra-Gln was also found very early in the apical exudate of S. alba in LD, together with more Glu; (iv) in A. thaliana induced by one DSD, the leaf export of Asn increased sharply, instead of Gln in LD. This agrees with Asn prevalence in C-limited plants. The putative role of amino acids in the transition to flowering is discussed.

Joanna Szpunar - One of the best experts on this subject based on the ideXlab platform.

  • A chemical speciation insight into the palladium( ii ) uptake and metabolism by Sinapis alba . Exposure to Pd induces the synthesis of a Pd–histidine complex
    Metallomics, 2019
    Co-Authors: Katarzyna Kińska, Beata Krasnodębska-ostręga, Joanna Kowalska, Katarzyna Bierla, Simon Godin, Hugues Preud'homme, Ryszard Lobinski, Joanna Szpunar
    Abstract:

    Palladium is recognized as a technologically critical element (TCE) because of its massive use in automobile exhaust gas catalytic converters. The release of Pd into the environment in the form of nanoparticles of various size and chemical composition requires an understanding of their metabolism by leaving organisms. We provide here for the first time a chemical speciation insight into the identity of the ligands produced or used by a plant Sinapis alba L. exposed in hydropony to Pd nanoparticles and soluble Pd (nitrate). The analytical method developed was based on the concept of 2D HPLC with parallel inductively coupled plasma mass spectrometry (ICP MS) and electrospray MS detection. Size exclusion chromatography – ICP MS of the plant extracts showed no difference between the speciation of Pd after the exposure to nanoparticles and after that to Pd2+ which indicated the reactivity and dissolution of Pd nanoparticles. A comparative investigation of the Pd speciation in a control plant extract spiked with Pd2+ and of an extract of a plant having metabolized palladium indicated the response of the Sinapis alba by the formation of a Pd–histidine complex. The complex was identified via Orbitrap MS; the HPLC-MS chromatogram produced two peaks at m/z 415.0341 each corresponding to a Pd–His2 complex. An investigation by ion-mobility MS revealed a difference in their collision cross section indicating that the complexes present varied in terms of spatial conformation. A number of other Pd complexes with different ligands (including nicotianamine) circulating in the plant were detected but these ligands were already observed in a control plant and their concentrations were not affected by the exposure to Pd.

  • single particle icp ms characterization of platinum nanoparticles uptake and bioaccumulation by lepidium sativum and Sinapis alba plants
    Journal of Analytical Atomic Spectrometry, 2016
    Co-Authors: Javier Jimenezlamana, Monika Asztemborska, Justyna Wojcieszek, Malgorzata Jakubiak, Joanna Szpunar
    Abstract:

    The increasing use of platinum in different forms including engineered nanoparticles (PtNPs) in a wide range of industrial applications and in particular in automotive catalysts is leading to a rising concern about their release and fate in the environment. This study investigates for the first time the uptake and fate of PtNPs by plants. Two model organisms Lepidium sativum and Sinapis alba were exposed to 70 nm PtNPs. An enzymatic digestion method was developed in order to extract intact PtNPs from the different plant tissues, optimizing different parameters in order to obtain the highest number of nanoparticles. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was developed to provide information about nanoparticle size, nanoparticle number concentration and the presence of dissolved platinum in the samples. The enzymatic treatment allowed the extraction of PtNPs from the different tissues without changing their oxidation or aggregation state. The presence of PtNPs at the nominal size in all tissues from both plants was observed. PtNPs with higher sizes than the nominal one were observed as well, suggesting the occurrence of an aggregation process. The presence of platinum in the dissolved form was not detected.

Youping Wang - One of the best experts on this subject based on the ideXlab platform.

  • molecular and cytological characterization of introgression lines in yellow seed derived from somatic hybrids between brassica napus and Sinapis alba
    Molecular Breeding, 2012
    Co-Authors: Jinjin Jiang, Yongtai Zhang, Rod J. Snowdon, Guohua Liang, Youping Wang
    Abstract:

    Polymerase chain reaction and genomic in situ hybridization techniques were conducted to demonstrate the genomic introgressions in somatic hybrid progenies between Brassica napus and Sinapis alba. With minisatellite core sequence 33.6 as primer, an S. alba-specific band (288 bp) was amplified in yellow seed progenies. No hybridization signals were found using the genomic DNA of S. alba as probe. In addition, degenerate primers were used for the detection of related genes based on the genes related to flavonoid biosynthesis of the model plant Arabidopsis thaliana. Sequencing results show that flavonoid pathway genes are highly conserved in A. thaliana, S. alba and B. napus, and present subtle differences because of genetic evolution. A specific band (1,672 bp) consistent with S. alba was characterized in the yellow seed lines. This study demonstrates that the new yellow seed germplasms, derived from backcrossed and self-crossed progenies of B. napus–S. alba hybrids, are stable and homozygous introgression lines with yellow seed color, and differ from existing yellow seed materials.

  • Phenotypic variation in progenies from somatic hybrids between Brassica napus and Sinapis alba
    Euphytica, 2009
    Co-Authors: Cunxu Wei, Jinjin Jiang, Yongtai Zhang, Rod J. Snowdon, Youping Wang
    Abstract:

    A number of variant phenotypes, such as long siliques, high density of pods, increased seed number per pod and yellow seed color resembling Sinapis alba, were selected from intergeneric somatic hybrids between Brassica napus and Sinapis alba through successive backcrosses. Resistance to Sclerotinia sclerotiorum among 24 BCF4 lines was also tested by inoculation with mycelia, and four lines showed stronger resistance than the resistant rapeseed variety ‘Zhongshuang 9’. Comparative anatomy studies on mature seed revealed that the seed coat pigments were mainly distributed in the palisade layer, which is considerably thinner in S. alba compared to B. napus. The area index of protein bodies in cotyledon cells was highest in S. alba, lowest in B. napus and intermediate in the intergeneric progenies. This study demonstrates that wide hybridization can enable exploitation of valuable trait diversity from S. alba for broadening the genetic basis for rapeseed breeding.

  • intergeneric somatic hybridization between brassica napus l and Sinapis alba l
    Journal of Integrative Plant Biology, 2005
    Co-Authors: Youping Wang, Karin Sonntag, Eicke Rudloff, Jianmin Chen
    Abstract:

    : Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%. ( Managing editor: Wei WANG)