National Institute of Plant Genome Research, New Delhi 110067, India.
Proc Natl Acad Sci U S A. 2010 Oct 12;107(41):17533-8. doi: 10.1073/pnas.1006265107. Epub 2010 Sep 20.
Protein deficiency is the most crucial factor that affects physical growth and development and that increases morbidity and mortality especially in developing countries. Efforts have been made to improve protein quality and quantity in crop plants but with limited success. Here, we report the development of transgenic potatoes with enhanced nutritive value by tuber-specific expression of a seed protein, AmA1 (Amaranth Albumin 1), in seven genotypic backgrounds suitable for cultivation in different agro-climatic regions. Analyses of the transgenic tubers revealed up to 60% increase in total protein content. In addition, the concentrations of several essential amino acids were increased significantly in transgenic tubers, which are otherwise limited in potato. Moreover, the transgenics also exhibited enhanced photosynthetic activity with a concomitant increase in total biomass. These results are striking because this genetic manipulation also resulted in a moderate increase in tuber yield. The comparative protein profiling suggests that the proteome rebalancing might cause increased protein content in transgenic tubers. Furthermore, the data on field performance and safety evaluation indicate that the transgenic potatoes are suitable for commercial cultivation. In vitro and in vivo studies on experimental animals demonstrate that the transgenic tubers are also safe for human consumption. Altogether, these results emphasize that the expression of AmA1 is a potential strategy for the nutritional improvement of food crops.
蛋白质缺乏是影响身体生长和发育的最关键因素，特别是在发展中国家，会增加发病率和死亡率。人们一直努力提高农作物的蛋白质质量和数量，但收效有限。在这里，我们报告了通过在适合不同农业气候区种植的七个基因型背景下，在块茎中特异性表达一种种子蛋白 AmA1（苋菜白蛋白 1），开发出具有增强营养价值的转基因马铃薯。对转基因块茎的分析表明，总蛋白质含量增加了高达 60%。此外，转基因块茎中几种必需氨基酸的浓度显著增加，而这些氨基酸在马铃薯中含量有限。此外，转基因植物还表现出增强的光合作用活性，伴随着总生物量的增加。这些结果令人瞩目，因为这种遗传操作还导致块茎产量适度增加。比较蛋白质组学分析表明，蛋白质组的再平衡可能导致转基因块茎中蛋白质含量增加。此外，田间表现和安全评估的数据表明，转基因马铃薯适合商业种植。实验动物的体外和体内研究表明，转基因块茎也可安全食用。总之，这些结果强调了 AmA1 的表达是改善粮食作物营养价值的一种潜在策略。
