References of "Périlleux, Claire"
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See detailCytokinin levels in leaves, leaf exudate and shoot apical meristem of Arabidopsis thaliana during floral transition
Corbesier, Laurent; Prinsen, Els; Jacqmard, Annie ULg et al

in Journal of Experimental Botany (2003), 54(392), 2511-2517

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis ... [more ▼]

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis thaliana has been successfully used to unravel signalling pathways by genetic and molecular approaches, but analyses are still required to determine the physiological signals involved in the control of floral transition. In this work, the putative role of cytokinins was investigated using vegetative plants of Arabidopsis (Columbia) induced to flower synchronously by a single 22 h long day. Cytokinins were analysed in leaf extracts, leaf phloem exudate and in the shoot apical meristem at different times during floral transition. It was found that, in both the leaf tissues and leaf exudate, isopentenyladenine forms of cytokinins increased from 16 h after the start of the long day. At 30 h, the shoot apical meristem of induced plants contained more isopentenyladenine and zeatin than vegetative controls. These cytokinin increases correlate well with the early events of floral transition. [less ▲]

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See detailC : N ratio increases in the phloem sap during floral transition of the long-day plants Sinapis alba and Arabidopsis thaliana
Corbesier, Laurent; Bernier, Georges ULg; Périlleux, Claire ULg

in Plant & Cell Physiology (2002), 43(6), 684-688

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 ... [more ▼]

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. [less ▲]

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See detailThe control of flowering: do genetical and physiological approaches converge ?
Périlleux, Claire ULg; Bernier, Georges ULg

in O'Neill, S. D.; Roberts, J. A. (Eds.) Plant Reproduction (2002)

Since the early 1990s, Arabidopsis thaliana has been studied as the species of choice of 'flowering geneticists'. Several pathways that either repress or promote flowering have been identified on the ... [more ▼]

Since the early 1990s, Arabidopsis thaliana has been studied as the species of choice of 'flowering geneticists'. Several pathways that either repress or promote flowering have been identified on the basis of (1) the flowering response of different genotypes to environmental factors (vernalization and photoperiod), (2) epistasis analyses, and (3) expression patterns of cloned genes in various backgrounds. Models attempting to include all information have been proposed repeatedly and their complexity is increasing with the bulk of data. In this review, we shall attempt to integrate into this genetical framework the physiological knowledge accumulated on a variety of plants by generations of researchers before the amost overnight breakthrough of Arabidopsis. [less ▲]

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See detailThe flowering process: On the track of controlling factors in Sinapis alba
Bernier, Georges ULg; Corbesier, Laurent; Périlleux, Claire ULg

in Russian Journal of Plant Physiology (2002), 49(4, JUL-AUG), 445-450

The major physiological theories of the control of the flowering process are first presented and their inferences tested in the long-day plant Sinapis alba. Then, the genetic analyses of the control of ... [more ▼]

The major physiological theories of the control of the flowering process are first presented and their inferences tested in the long-day plant Sinapis alba. Then, the genetic analyses of the control of flowering time in Arabidopsis thaliana are also summarized with a brief overview of the several pathways, each including several genes, identified. Clearly, both the experimental data of physiological experiments and the multiplicity of interacting genetic pathways best support the theory of the multifactorial control of flowering. This is further shown by the fact that a critical gene expressed in the shoot meristem at floral transition in S. alba, MADS A (orthologous to A. thaliana SOC1), can be upregulated by a single dose of a cytokinin or a gibberellin, without leading to flowering. This indicates that the floral shift requires upregulation of other genes by other factors. [less ▲]

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See detailN content of phloem and xylem exudates during the transition to flowering in Sinapis alba and Arabidopsis thaliana
Corbesier, Laurent; Havelange, Andrée ULg; Lejeune, Pierre et al

in Plant, Cell & Environment (2001), 24

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 ... [more ▼]

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. [less ▲]

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See detailSuppressor mutagenesis of over-expression of the CONSTANS gene in Arabidopsis
Onouchi, Hitoshi; Samach, Alon; Igeño, Isabel et al

in Plant & Cell Physiology (2000), 41(supplement), 127

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See detailChanges in amino acid content during floral induction in the leaf exudate collected form the long day plant Arabidopsis thaliana
Corbesier, Laurent; Lejeune, Pierre; Bernier, Georges et al

Poster (2000)

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See detailMutagenesis of plants overexpressing CONSTANS demonstrates novel interactions among Arabidopsis flowering-time genes.
Onouchi, Hitoshi; Igeno, M. Isabel; Périlleux, Claire ULg et al

in Plant Cell (2000), 12(6), 885-900

CONSTANS (CO) promotes flowering of Arabidopsis in response to long photoperiods. Transgenic plants carrying CO fused with the cauliflower mosaic virus 35S promoter (35S::CO) flowered earlier than did the ... [more ▼]

CONSTANS (CO) promotes flowering of Arabidopsis in response to long photoperiods. Transgenic plants carrying CO fused with the cauliflower mosaic virus 35S promoter (35S::CO) flowered earlier than did the wild type and were almost completely insensitive to length of day. Genes required for CO to promote flowering were identified by screening for mutations that suppress the effect of 35S::CO. Four mutations were identified that partially suppressed the early-flowering phenotype caused by 35S::CO. One of these mutations, suppressor of overexpression of CO 1 (soc1), defines a new locus, demonstrating that the mutagenesis approach is effective in identifying novel flowering-time mutations. The other three suppressor mutations are allelic with previously described mutations that cause late flowering. Two of them are alleles of ft, indicating that FT is required for CO to promote early flowering and most likely acts after CO in the hierarchy of flowering-time genes. The fourth suppressor mutation is an allele of fwa, and fwa soc1 35S::CO plants flowered at approximately the same time as co mutants, suggesting that a combination of fwa and soc1 abolishes the promotion of flowering by CO. Besides delaying flowering, fwa acted synergistically with 35S::CO to repress floral development after bolting. The latter phenotype was not shown by any of the progenitors and was most probably caused by a reduction in the function of LEAFY. These genetic interactions suggest models for how CO, FWA, FT, and SOC1 interact during the transition to flowering. [less ▲]

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See detailAre CAB gene expression and flowering under the control of the same clock in Lolium temulentum Ceres ?
Hustin, Cécile; Bernier, Georges ULg; Périlleux, Claire ULg

in Biological Rhythm Research (1999), 30

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See detailGuide des travaux pratiques de Physiologie végétale
Périlleux, Claire ULg

Learning material (1999)

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See detailPhysiological analysis of the floral transition
Bernier, Georges ULg; Corbesier, Laurent; Périlleux, Claire ULg et al

in Cockshull, K. E.; Gray, D.; Seymour, G. B. (Eds.) et al Genetic and Environmental Manipulation of Horticultural Crops (1998)

This chapter summarizes the changes in contents of the phloem sap that were found at the time of floral induction in different photoperiodic species: Arabidopsis thaliana, Sinapis alba, Lolium temulentum ... [more ▼]

This chapter summarizes the changes in contents of the phloem sap that were found at the time of floral induction in different photoperiodic species: Arabidopsis thaliana, Sinapis alba, Lolium temulentum and Xanthium strumarium. Changes affecting contents in carbohydrates, cytokinins, amino acids, polyamines and inorganis ions are discussed in the context of 'florigen quest'. [less ▲]

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See detailLeaf carbohydrate status in Lolium temulentum during the induction of flowering
Périlleux, Claire ULg; Bernier, Georges ULg

in New Phytologist (1997), 135(1), 59-66

Unifoliated plants of Lolium temulentum L. ev. Ceres, a qualitative long-day grass, were induced to flower by one 24-h long day (LD) or by one 8-h short day (SD) advanced by 1 2 h in the normal regime, so ... [more ▼]

Unifoliated plants of Lolium temulentum L. ev. Ceres, a qualitative long-day grass, were induced to flower by one 24-h long day (LD) or by one 8-h short day (SD) advanced by 1 2 h in the normal regime, so-called 'displaced short day' (DSD). Standard light for SD and DSD was a mixture of fluorescence and incandescence at 400 µmol m2 s-1 whereas the extension period of the 24-h LD was solely incandescence at 10-15 µmol m2 s-1. The DSD system was first characterized by the timings of floral induction, stimulus translocation and apical development. Carbohydrates in the blade tissues and in leaf exudate were analysed comparatively in vegetative and induced plants. Fructans were not detected in the leaf tissues whereas sucrose and starch were found to be present in similar amounts. In SD, their contents exhibited a diurnal fluctuation and were not in large excess. The common change observed during the two inductive treatments was that starch remained at a high level during the LD extension, even though the lighting was unsuitable for photosynthesis, and increased transiently in DSD. Sucrose was the major sugar contained in the leaf exudate. Its content increased when flowering was induced, but not at the same time in the two systems. In LD, sucrose exudation rose when plants were returned to standard light after the inductive cycle, i.e. after the LD stimulus had left the leaf blade. By contrast, during the DSD, sucrose was transported at the same time as the floral stimulus. Results are discussed together with the methods used to time stimulus translocation and their implications. [less ▲]

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See detailBiological clock and photoperiodism in Lolium temulentum Ceres
Périlleux, Claire ULg; Hustin, Cécile; Bernier, Georges ULg

in Journal of Experimental Botany (1997), 48

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See detailDarkness promotes flowering in the absolute long-day requiring plant, Lolium temulentum L. Ceres
Périlleux, Claire ULg; Bernier, Georges ULg; Kinet, Jean-Marie

in Journal of Experimental Botany (1997), 48(307), 349--351

Vegetative plants of the long-day grass Lolium temulentum L. Ceres were exposed to threshold long days or light breaks. Protracted darkness given just afterwards clearly promoted flowering and was weakly ... [more ▼]

Vegetative plants of the long-day grass Lolium temulentum L. Ceres were exposed to threshold long days or light breaks. Protracted darkness given just afterwards clearly promoted flowering and was weakly inductive on its own. The promotive effect of darkness was restricted to floral induction since further apical development was weak. [less ▲]

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See detailChanges in gene expression in the leaf of Lolium temulentum L. Ceres during the photoperiodic induction of flowering
Périlleux, Claire ULg; Ongena, Philippe; Bernier, Georges ULg

in Planta (1996), 200(1), 32-40

Unifoliated plants of Lolium temulentum L. Ceres were induced to flower by a unique 24-h long day (LD) consisting of the extension of the regular 8-h short day (SD) (400 µmol photons·m-2·s-1, fluorescence ... [more ▼]

Unifoliated plants of Lolium temulentum L. Ceres were induced to flower by a unique 24-h long day (LD) consisting of the extension of the regular 8-h short day (SD) (400 µmol photons·m-2·s-1, fluorescence + incandescence) with incandescence at 10–15 µmol photonsm -2·s-1. The polyadenylated-RNA complement of leaf blade tissues was analysed at 4-h intervals during the photoperiod extension in LD vs. SD, by using two-dimensional polyacrylamide gel electrophoresis to resolve in-vitro-translated products. Of the 991 spots that were analysed, none appeared or disappeared during the inductive cycle, i.e. no qualitative effect of floral induction was detected, at any time. Sixty-eight spots were found whose intensity was influenced by lengthening of the photoperiod; 50 of them, i.e. ca. 5 of the population analysed, were affected before the end of the extension period and were thus potentially related to floral induction. Many of these RNAs were not quantitatively constant during a 24-h cycle in SD. Seven of them oscillated according to the ‘light-on’ and the ‘light-off’ signals, among which three seemed to be controlled by phytochrome since their relative amount increased under the standard light conditions but decreased under incandescence even faster than in darkness. The large majority of other RNAs varied with a timing that was not clearly driven by the alternation of light and darkness, indicating that genes related to the biological clock may be especially sensitive to the lengthening of the photoperiod. Furthermore, seven spots were observed that underwent a phase-shift in LD, which consisted, for six of them, of a phase advance of 4–8 h. The steady-state level of CAB mRNA was analysed because the CAB gene family (encoding the chlorophyll a/b-binding proteins of the light-harvesting complexes) is known to be controlled both by the biological clock and phytochrome. In SD, the level was high in the light and low in darkness; the fluctuation was conducted by a circadian rhythm. When plants were exposed to the inductive LD, the peak of mRNA accumulation that was expected according to the endogenous rhythmicity was abolished, possibly because of the change in light quality during the LD extension. [less ▲]

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