Altenbach Susan B, Allen Paul V
USDA-ARS Western Regional Research Center, Albany, CA, USA.
GM Crops. 2011 Jan-Mar;2(1):66-73. doi: 10.4161/gmcr.2.1.15884.
Complex groups of proteins determine the unique functional properties of wheat flour and are sometimes responsible for food intolerances and allergies in individuals that consume wheat products. Transgenic approaches can be used to explore the functions of different flour proteins, but are limited to the few wheat cultivars that can be transformed and also by the lack of detailed information about genes and proteins expressed in grain from those cultivars. The US bread wheat Butte 86 has been extensively characterized and a comprehensive proteome map was developed in which flour proteins were distinguished by mass spectrometry and associated with specific gene sequences. Here, this information has been used to design an RNA interference construct to silence the expression of genes encoding omega gliadins that trigger the food allergy wheat-dependent exercise-induced anaphylaxis (WDEIA). The construct was introduced into immature embryos from Butte 86 using biolistics and bialaphos-resistant plants were regenerated. Stable transformation and inheritance of the transgene were confirmed by PCR. Analysis of proteins in grain from transgenic plants demonstrated that the omega-5 gliadins were either absent or substantially reduced relative to non-transformed controls. The ability to genetically transform Butte 86 makes it possible to alter flour composition in a targeted manner in a commercial US wheat cultivar and should accelerate future research on flour quality and immunogenic potential.
复杂的蛋白质组决定了小麦粉独特的功能特性，有时还会导致食用小麦制品的个体出现食物不耐受和过敏反应。转基因方法可用于探索不同面粉蛋白的功能，但仅限于少数可转化的小麦品种，并且还受到缺乏这些品种籽粒中表达的基因和蛋白质详细信息的限制。美国面包小麦品种巴特86已得到广泛研究，并绘制了一份全面的蛋白质组图谱，其中通过质谱法区分了面粉蛋白，并将其与特定基因序列相关联。在此，利用这些信息设计了一种RNA干扰构建体，以沉默编码引发食物过敏——小麦依赖运动诱发过敏反应（WDEIA）的ω-醇溶蛋白的基因表达。通过生物枪法将该构建体导入巴特86的未成熟胚，并再生出抗bialaphos的植株。通过PCR证实了转基因的稳定转化和遗传。对转基因植株籽粒中的蛋白质分析表明，相对于未转化的对照，ω-5醇溶蛋白要么不存在，要么显著减少。对巴特86进行遗传转化的能力使得在美国商业小麦品种中有针对性地改变面粉成分成为可能，并且应该会加速未来关于面粉质量和免疫原性潜力的研究。
