Prescha A, Swiedrych A, Biernat J, Szopa J
Department of Food Science and Nutrition, Medical University, Nankiera 1, 50-140 Wrocław, Poland.
J Agric Food Chem. 2001 Aug;49(8):3638-43. doi: 10.1021/jf010258o.
Recently, transgenic potato plants were created with overexpression of the 14-3-3 protein derived from Cucurbita pepo. Detailed analysis of those plants suggested that the function of the isolated 14-3-3 isoform is in the control of carbohydrate and lipid metabolism in the plants. 14-3-3 protein overexpression gave rise to an increase in soluble sugar and catecholamine contents in both leaves and tubers. It is proposed that 14-3-3 protein affects carbohydrate metabolism in potato plants via regulation of catecholamine synthesis. Furthermore, genetically modified potato tubers with 14-3-3 protein overexpression showed changes in lipid content and composition. The transgenic potato tubers contained 69% more total fat compared to the wild-type plant. Separation of tuber lipids into polar and nonpolar fractions revealed that the transgenic potato tubers contained almost 3 times more nonpolar lipids than the control. Analysis of fatty acid composition, conducted by the means of gas chromatography, showed that linoleic acid was the main fatty acid present in the tubers of both modified and control potato plants. In the nonpolar fraction of the fat of the transgenic tubers the unsaturated fatty acids exhibited a higher participation in the sum of all fatty acids.
最近，通过过量表达源自西葫芦的14-3-3蛋白培育出了转基因马铃薯植株。对这些植株的详细分析表明，分离出的14-3-3同工型的功能在于控制植物中的碳水化合物和脂质代谢。14-3-3蛋白的过量表达导致叶片和块茎中可溶性糖和儿茶酚胺含量增加。有人提出，14-3-3蛋白通过调节儿茶酚胺合成来影响马铃薯植株中的碳水化合物代谢。此外，过量表达14-3-3蛋白的转基因马铃薯块茎在脂质含量和组成上出现了变化。与野生型植株相比，转基因马铃薯块茎的总脂肪含量多69%。将块茎脂质分离为极性和非极性部分显示，转基因马铃薯块茎的非极性脂质含量几乎是对照的3倍。通过气相色谱法进行的脂肪酸组成分析表明，亚油酸是改良马铃薯植株和对照马铃薯植株块茎中的主要脂肪酸。在转基因块茎脂肪的非极性部分中，不饱和脂肪酸在所有脂肪酸总量中的占比更高。
