Improving health benefits of wheat by increasing resistant starch

描述(申请人提供)：糖尿病和肥胖症是一个日益严重的公共卫生问题，每年影响着更多的人口。很大一部分人是糖尿病前期，有可能进展为糖尿病。食物的选择会影响所有这些健康问题。这项提议的总体目标是提高小麦中的抗性淀粉水平，小麦是我们饮食的主要组成部分。抗性淀粉具有许多有益健康的特性。它是淀粉的一部分，在较低的肠道中逃脱消化，而在大肠中发酵。正因为如此，抗性淀粉不会导致餐后血糖迅速上升；相反，葡萄糖释放到血液中的速度会更慢，从而导致饱腹感增加。低位肠道中抗性淀粉的发酵也会导致短链脂肪酸的产生，这有助于促进结肠健康。我们建议开发具有非常高水平抗性淀粉的小麦新品种。通过增加直链淀粉的水平，抗性淀粉的水平也会增加。抗性淀粉也与总膳食纤维的水平有关，因为它被缓慢地消化；因此，增加直链淀粉也会增加纤维含量。在初步工作中，我们利用TILLING(靶向诱导基因组局部损伤)培育了一个直链淀粉水平中等的小麦品系，这是由于利用TILLING(靶向诱导的基因组局部损伤)改变了淀粉生物合成途径中的一种酶。分耕是一种新的非转基因技术，是诱变育种的目标选择变异。为了开发出可以商业化的高直链淀粉小麦，我们建议将连锁淀粉生物合成基因的突变结合起来。获得必要的连锁突变的可行性将在第一阶段得到证明。考虑到我们小麦耕作文库的规模和突变频率，该项目成功的可能性很高。其余必要的突变将在第二阶段被发现，并通过育种结合起来，产生非常高的直链淀粉品种。我们已经申请了快速通道SBIR，基于我们初步数据的强度和商业化的可能性很高，因为比目前可用的抗性淀粉来源多得多，抗性淀粉的使用受到限制。因为业界对该产品的兴趣程度很高。高抗淀粉小麦可以添加到小麦中，这种产品在我们的饮食中普遍存在，这种产品可能会对健康产生重大的积极影响。 与公共卫生相关：糖尿病和肥胖症是一个日益严重的公共卫生问题，每年影响着更多的人口。食物的选择会影响这些健康问题，而富含抗性淀粉的食物具有帮助对抗这些疾病的有益效果。这项提议的总体目标是开发具有非常高水平的抗性淀粉的新小麦品种，这将对健康产生积极影响。)

DESCRIPTION (provided by applicant): The conditions of diabetes and obesity are a growing public health concern affecting more of the population every year. A large segment of the population is pre-diabetic potentially progressing towards diabetes. Food choices impact all of these health problems. The overall goal of this proposal is to increase resistant starch levels in wheat, a principle part of our diet. Resistant starch has many beneficial health properties. It is the portion of starch that escapes digestion in the lower intestine and is instead fermented in the large intestine. Because of this, resistant starch does not cause a rapid rise in glucose after a meal; instead glucose is released more slowly into the bloodstream and leads to an increased feeling of satiety. Fermentation of resistant starch in the lower intestine also leads to short chain fatty acid production that helps promote colon health. We propose to develop novel wheat cultivars with very high levels of resistant starch. By increasing levels of amylose, one of the components of starch, resistant starch levels increase. Resistant starch is also correlated with levels of total dietary fiber because it is slowly digested; so increased amylose increases fiber content as well. In preliminary work, we developed a wheat line with moderate amylose levels due to the alteration of an enzyme in the starch biosynthetic pathway using TILLING (Targeting Induced Local Lesions in Genomes). TILLING is a novel non-GM (genetic modification) technique that is a target-selected variation of mutation breeding. In order to develop very high amylose wheat for a product that can be commercialized, we propose to combine mutations in linked starch biosynthetic genes. The feasibility of obtaining the necessary linked mutations will be demonstrated during Phase I. This project has a high likelihood of success given the size and mutation frequency of our wheat TILLING library. The rest of the necessary mutations will be discovered during Phase II and combined through breeding to produce the very high amylose variety. We have applied for the Fast Track SBIR based on the strength of our preliminary data and the high likelihood of commercialization due to the many more foods than currently available sources of resistant starch whose use is limited. Because level of interest from the industry in this product. High resistant starch wheat can be incorporated into wheat is pervasive in our diets, this product could have a major positive impact on health. PUBLIC HEALTH RELEVANCE: The conditions of diabetes and obesity are a growing public health concern affecting more of the population every year. Food choices impact these health problems, and foods high in resistant starch have beneficial effects that help combat these conditions. The overall goal of this proposal is to develop novel wheat cultivars with very high levels of resistant starch that would positively impact health. )