The metabolic profile of the 14-3-3 repressed transgenic potato tubers

Abstract

Recently potato three transgenes were created, all with 14-3-3 repression. Two different isoforms were repressed, those previously called 29G (J5 line) and 20R (J4 line), and additionally transgenic plants with repression of both isoforms (G1 line) were created. The plants were analysed for enzyme activities and metabolite levels. Detailed analysis of those plants suggested that a function of the isolated 14-3-3 isoform is in the control of plant carbohydrate metabolism and nitrogen fixation. Sucrose phosphate synthase and nitrate reductase were the most highly affected of the enzymes measured in transgenic tubers and leaves, respectively. In in vitro experiment, these enzymes were also significantly affected by 14-3-3 proteins. Thus, the results obtained are consistent with those from transgenic plants analysis and the in vitro data can be directly transferred to in vivo situation. Of many measured metabolites the significant increase in sucrose, starch, aspartic and glutamic acids, glutamine, malic and citric acids was detected which suggest the potential role of 14-3-3 in TCA cycle regulation.