Serge Delrot | Université de Bordeaux (original) (raw)
Papers by Serge Delrot
Http Dx Doi Org 10 1094 Mpmi 19 1103, Feb 14, 2007
Type I lipid transfer proteins (LTPs) are basic, 9-kDa cystein-rich proteins believed to be invol... more Type I lipid transfer proteins (LTPs) are basic, 9-kDa cystein-rich proteins believed to be involved in plant defense mechanisms. A 2,100-bp fragment containing the coding region of Vitis vinifera lipid transfer protein 1 (VvLTP1) and 1,420-bp of its promoter region was isolated by screening a grape genomic library. In silico analysis revealed several putative, defense-related, cis-regulatory elements such as W- and MYB-boxes, involved in the binding of WRKY and MYB transcription factors, respectively. The 5'-truncated versions of the VvLTP1 promoter were generated, cloned in front of the beta-glucuronidase (GUS) reporter gene, and introduced in tobacco plants and grapevine cell suspensions using Agrobacterium spp. Single MYB- and the W-boxes identified on the 0.250-kbp fragment were sufficient to induce GUS activity in transgenic tobacco plants after transient expression of MYB and WRKY. Ergosterol, a nonspecific fungal elicitor, induced GUS activity in transgenic grapevine cell suspensions transformed with the 1,420- and 750-bp promoter containing a palindromic arrangement of two W-boxes but not the 650- or 250-bp fragment, where only one W-box was present. Moreover, ergosterol triggered WRKY, VvLTP1, and stilbene synthase gene expression in grape plantlets and enhanced protection against Botrytis cinerea. The molecular basis of ergosterol-induced protection is discussed.
... Identifier: Bonnemain, J. L. ... Document details. Title Recent advances in phloem transport ... more ... Identifier: Bonnemain, J. L. ... Document details. Title Recent advances in phloem transport and assimilate compartmentation. Editors Bonnemain, JL;Delrot, S.;Lucas, WJ;Dainty, J. Book Recent advances in phloem transport and assimilate compartmentation. 1991 pp. xiv + 344 pp. ...
Comptes Rendus Des Seances De L Academie Des Sciences Serie Iii Sciences De La Vie, 1992
Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +/... more Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +//3-O-methylglucose (3-O-MeG) symport in liverworts. The effects of this compound on the uptake of (U-¹â´C) sucrose and of (¹â´C) 3-O-MeG by broadbean (Vicia faba L.) leaf discs were studied. Leaf discs without lower epidermis were preincubated in the dark for 30 min (fresh discs) or
Plant physiology
The transport of [''C]glycyl-glycine (Cly-Cly) has been characterized in leaf discs from mature e... more The transport of [''C]glycyl-glycine (Cly-Cly) has been characterized in leaf discs from mature exporting leaves of broad bean (Vicia faba 1.). In terms of glycine (Cly) equivalents, the rate of transport of Cly-Cly was similar to that of Cly uptake. Uptake of Cly-Cly was localized mainly in the mesophyll cells, with little accumulation in the veins. It was optimal at pH 6.0, sensitive to thiol reagents and metabolic inhibitors, and exhibited a single saturable phase with an apparent Michaelis constant of 16 mM. Cly-Cly did not inhibit the uptake of labeled Cly. Addition of Cly-Cly induced a concentration-dependent pH rise in the medium, showing that peptide uptake is mediated with proton co-transport. Cly-Gly also induced a concentration-dependent transmembrane depolarization of mesophyll cells with an apparent Michaelis constant of 15 mM. This depolarization was followed by a transient hyperpolarization. When present at a 10-fold excess, various peptides and tripeptides were able to inhibit Cly-Cly uptake with the following decreasing order of efficiency: Cly-Cly-Cly = leucine-Cly > Cly-tyrosine > Cly-glutamine = Cly-glutamic acid > Clyphenylalanine > Cly-threonine > Cly-aspartic acid = Cly-asparagine = aspartic acid-Cly. Cly inhibited the uptake of Cly-Gly only slightly, whereas tetraCly and the tripeptide glutathione were not inhibitory. The dipeptides inhibiting Gly-Gly uptake also induced changes in the transmembrane potential difference of mesophyll cells and were able to affect in a complex way the response normally induced by Cly-Cly. Altogether, the data demonstrate the existence of a low-affinity, broad-specificity H+/peptide co-transporter at the plasma membrane of mesophyll cells. The physiological importance of this transporter for the exchange of nitrogenous compounds in mature leaves remains to be determined, as do the details of the electrophysiological events induced by the dipeptides.
Planta, Jan 3, 2015
Light exclusion reduces the concentration and modifies the composition of grape anthocyanins, by ... more Light exclusion reduces the concentration and modifies the composition of grape anthocyanins, by altering the expression of genes involved in anthocyanin biosynthesis and transport, in a cultivar- and tissue-specific manner. Unlike most grapes, teinturier grapes accumulate anthocyanins both in skin and flesh. However, the concentration and composition of anthocyanins in both tissues differ, providing a valuable system to study tissue-specific regulation of anthocyanin synthesis. Furthermore, little is known about the mechanisms controlling the sensitivity of anthocyanin accumulation to light. Here, light was excluded from Gamay (white-fleshed) and Gamay Fréaux (teinturier mutant) berries throughout berry development. Under light-exposed conditions, the skin of Gamay Fréaux accumulated the highest level of anthocyanins, followed by the skin of Gamay, while the pulp of Gamay Fréaux had much lower anthocyanins than the skins. Network analysis revealed the same order on the number of si...
Http Dx Doi Org 10 1094 Mpmi 19 1103, Feb 14, 2007
Type I lipid transfer proteins (LTPs) are basic, 9-kDa cystein-rich proteins believed to be invol... more Type I lipid transfer proteins (LTPs) are basic, 9-kDa cystein-rich proteins believed to be involved in plant defense mechanisms. A 2,100-bp fragment containing the coding region of Vitis vinifera lipid transfer protein 1 (VvLTP1) and 1,420-bp of its promoter region was isolated by screening a grape genomic library. In silico analysis revealed several putative, defense-related, cis-regulatory elements such as W- and MYB-boxes, involved in the binding of WRKY and MYB transcription factors, respectively. The 5'-truncated versions of the VvLTP1 promoter were generated, cloned in front of the beta-glucuronidase (GUS) reporter gene, and introduced in tobacco plants and grapevine cell suspensions using Agrobacterium spp. Single MYB- and the W-boxes identified on the 0.250-kbp fragment were sufficient to induce GUS activity in transgenic tobacco plants after transient expression of MYB and WRKY. Ergosterol, a nonspecific fungal elicitor, induced GUS activity in transgenic grapevine cell suspensions transformed with the 1,420- and 750-bp promoter containing a palindromic arrangement of two W-boxes but not the 650- or 250-bp fragment, where only one W-box was present. Moreover, ergosterol triggered WRKY, VvLTP1, and stilbene synthase gene expression in grape plantlets and enhanced protection against Botrytis cinerea. The molecular basis of ergosterol-induced protection is discussed.
... Identifier: Bonnemain, J. L. ... Document details. Title Recent advances in phloem transport ... more ... Identifier: Bonnemain, J. L. ... Document details. Title Recent advances in phloem transport and assimilate compartmentation. Editors Bonnemain, JL;Delrot, S.;Lucas, WJ;Dainty, J. Book Recent advances in phloem transport and assimilate compartmentation. 1991 pp. xiv + 344 pp. ...
Comptes Rendus Des Seances De L Academie Des Sciences Serie Iii Sciences De La Vie, 1992
Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +/... more Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +//3-O-methylglucose (3-O-MeG) symport in liverworts. The effects of this compound on the uptake of (U-¹â´C) sucrose and of (¹â´C) 3-O-MeG by broadbean (Vicia faba L.) leaf discs were studied. Leaf discs without lower epidermis were preincubated in the dark for 30 min (fresh discs) or
Plant physiology
The transport of [''C]glycyl-glycine (Cly-Cly) has been characterized in leaf discs from mature e... more The transport of [''C]glycyl-glycine (Cly-Cly) has been characterized in leaf discs from mature exporting leaves of broad bean (Vicia faba 1.). In terms of glycine (Cly) equivalents, the rate of transport of Cly-Cly was similar to that of Cly uptake. Uptake of Cly-Cly was localized mainly in the mesophyll cells, with little accumulation in the veins. It was optimal at pH 6.0, sensitive to thiol reagents and metabolic inhibitors, and exhibited a single saturable phase with an apparent Michaelis constant of 16 mM. Cly-Cly did not inhibit the uptake of labeled Cly. Addition of Cly-Cly induced a concentration-dependent pH rise in the medium, showing that peptide uptake is mediated with proton co-transport. Cly-Gly also induced a concentration-dependent transmembrane depolarization of mesophyll cells with an apparent Michaelis constant of 15 mM. This depolarization was followed by a transient hyperpolarization. When present at a 10-fold excess, various peptides and tripeptides were able to inhibit Cly-Cly uptake with the following decreasing order of efficiency: Cly-Cly-Cly = leucine-Cly > Cly-tyrosine > Cly-glutamine = Cly-glutamic acid > Clyphenylalanine > Cly-threonine > Cly-aspartic acid = Cly-asparagine = aspartic acid-Cly. Cly inhibited the uptake of Cly-Gly only slightly, whereas tetraCly and the tripeptide glutathione were not inhibitory. The dipeptides inhibiting Gly-Gly uptake also induced changes in the transmembrane potential difference of mesophyll cells and were able to affect in a complex way the response normally induced by Cly-Cly. Altogether, the data demonstrate the existence of a low-affinity, broad-specificity H+/peptide co-transporter at the plasma membrane of mesophyll cells. The physiological importance of this transporter for the exchange of nitrogenous compounds in mature leaves remains to be determined, as do the details of the electrophysiological events induced by the dipeptides.
Planta, Jan 3, 2015
Light exclusion reduces the concentration and modifies the composition of grape anthocyanins, by ... more Light exclusion reduces the concentration and modifies the composition of grape anthocyanins, by altering the expression of genes involved in anthocyanin biosynthesis and transport, in a cultivar- and tissue-specific manner. Unlike most grapes, teinturier grapes accumulate anthocyanins both in skin and flesh. However, the concentration and composition of anthocyanins in both tissues differ, providing a valuable system to study tissue-specific regulation of anthocyanin synthesis. Furthermore, little is known about the mechanisms controlling the sensitivity of anthocyanin accumulation to light. Here, light was excluded from Gamay (white-fleshed) and Gamay Fréaux (teinturier mutant) berries throughout berry development. Under light-exposed conditions, the skin of Gamay Fréaux accumulated the highest level of anthocyanins, followed by the skin of Gamay, while the pulp of Gamay Fréaux had much lower anthocyanins than the skins. Network analysis revealed the same order on the number of si...