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Asma Ben Ghnaya Annick Hourmant Stéphane Cerantola Nelly Kervarec Jean Yves Cabon Michel Branchard Gilbert Charles 《Plant Cell, Tissue and Organ Culture》2010,102(2):191-197
To gain more insight into the impact of zinc on the primary metabolites in rapeseed, plants were regenerated in vitro in the
presence of zinc (0.1–1 mM), acclimatized, transferred to a greenhouse, and treated with 2 mM ZnSO4. The main metabolites, including soluble carbohydrates and free amino acids, were analyzed by nuclear magnetic resonance
spectroscopy, and further confirmed by spectrophotometry and enzymatic analyses. Exposure of these greenhouse-grown plants
to ZnSO4 led to both a significant rise of the total amino acid level and an increase of proline accumulation in the different tissues.
Moreover, the control plants, regenerated without zinc stress, exhibited a significant reduction of soluble carbohydrate levels,
whereas the plants derived from Zn-treated regenerants exhibited significantly higher levels of both glucose and sucrose.
These levels increased proportionally with the Zn concentration in the regeneration step. 相似文献
894.
Veronique van den Berghe Elke Stappers Bram Vandesande Jordane Dimidschstein Roel Kroes Annick Francis Andrea Conidi Flore Lesage Ruben Dries Silvia Cazzola Geert Berx Nicoletta Kessaris Pierre Vanderhaeghen Wilfred van IJcken Frank G. Grosveld Steven Goossens Jody J. Haigh Gord Fishell Eve Seuntjens 《Neuron》2013,77(1):70-82
895.
Simon Vitecek Annick Maria Catherine Blais Line Duportets Cyril Gaertner Marie-Cécile Dufour David Siaussat Stéphane Debernard Christophe Gadenne 《Hormones and behavior》2013,63(5):700-708
In many animals, male copulation is dependent on the detection and processing of female-produced sex pheromones, which is generally followed by a sexual refractory post-ejaculatory interval (PEI). In the male moth, Agrotis ipsilon, this PEI is characterized by a transient post-mating inhibition of behavioral and central nervous responses to sex pheromone, which prevents males from re-mating until they have refilled their reproductive tracts for a potential new ejaculate. However, the timing and possible factors inducing this rapid olfactory switch-off are still unknown. Here, we determined the initial time delay and duration of the PEI. Moreover, we tested the hypothesis that the brain, the testis and/or the sex accessory glands (SAGs) could produce a factor inducing the PEI. Lastly, we investigated the possible involvement of ecdysteroids, hormones essential for development and reproduction in insects, in this olfactory plasticity. Using brain and SAG cross-injections in virgin and newly-mated males, surgical treatments, wind tunnel behavioral experiments and EIA quantifications of ecdysteroids, we show that the PEI starts very shortly after the onset of copulation, and that SAGs contain a factor, which is produced/accumulated after copulation to induce the PEI. Moreover, SAGs were found to be the main source of ecdysteroids, whose concentration decreased after mating, whereas it increased in the haemolymph. 20-Hydroxyecdysone (20E) was identified as the major ecdysteroid in SAGs of A. ipsilon males. Finally, 20E injections did not reduce the behavioral pheromone response of virgin males. Altogether our data indicate that 20E is probably not involved in the PEI. 相似文献