Jasmonates and Na-orthovanadate promote resveratrol production in Vitis vinifera cv. Barbera cell cultures.

Here the effect of jasmonic acid, methyljasmonate and Na-orthovanadate on the production of resveratrol was studied in Vitis vinifera cv. Barbera cell suspension cultures. Na-orthovanadate at 0.1 mm and 1 mm concentration was efficient in promoting the production and/or accumulation and release in the culture medium of cis-resveratrol while trans-resveratrol levels were not affected by this treatment. Methyljasmonate was highly effective in stimulating both trans- and cis-resveratrol endogenous accumulation, as well as their release into the culture medium. Cis-resveratrol was absent or detected in very low amounts in the controls. Jasmonic acid was less efficient than methyljasmonate in promoting endogenous resveratrol accumulation, but it stimulated the release in the culture medium especially of cis-resveratrol. Gel analysis was performed on control and 10 microm MeJA treated cell suspensions. Results showed an up-regulation of the stilbene synthase demonstrating that MeJA stimulated the synthesis ex-novo of this protein.

Expression proteomics identifies biochemical adaptations and defense responses in transgenic plants with perturbed polyamine metabolism.

Soluble proteins from leaves of transgenic tobacco plants with perturbed polyamine metabolism, caused by S-adenosylmethionine decarboxylase overexpression, were analysed by comparative proteomics. A group of proteins was found to be increasingly repressed, in parallel with the degree of polyamine perturbation, in each of the three independent transgenic lines. These were identified as isoforms of chloroplast ribonucleoproteins, known to be involved in chloroplast mRNA stability, processing and translation. Another group of eight proteins strongly induced in the most metabolically perturbed line was identified as multiple, uncharacterised isoforms of the defense protein PR-1, a known marker for systemic acquired resistance.