小麦籽粒中铁元素积累的分子机制分析

Iron is an essential micronutrient for human nutrition, and globally over two billion people are suffering from anemia due to iron deficiency in their diet. Grains of staple crops such as cereals including wheat, rice and maize are the major source of this iron. So, enhancing the content of iron in grains is very important for providing optimum Fe to human health. Wheat is one of the major crops in China and therefore, people relying strongly on wheat-based diet. However, the available wheat varieties contain genetically low amount of Fe due to which many people are suffering from Fe deficiency. Therefore, there is an urgent need to determine and analyse the Fe content in the wheat germplasm, and to study the genetic mechanism of Fe and further to clone the important genes that regulate Fe in wheat. In this project, a diverse wheat germplasm will be evaluated for Fe content to find the important loci that have potential for increasing the Fe content in wheat. For this, QTL mapping and GWAS will be used to map these important genes. These important genes will also be cloned by using the molecular biology tools and will be functionally characterized through gene knockout system and plant transformation.

铁是人体生长和发育所必需的一种微量元素，但也是人体较易缺乏的微量元素之一，世界上大约有三分之二的人群受缺铁的困扰，缺铁而引起的贫血病发病率高达世界总人口的三分之一。种子作为很多主食作物的可食部分其铁的含量直接影响到人类的身体健康。生物强化即通过遗传改良来提高食物中铁元素含量是最经济有效的方法。小麦是我国主要的粮食作物之一，且我国的小麦大部分都种植于土壤碱性的北方，其籽粒中铁的含量都很低。研究小麦籽粒中影响铁元素积累的关键基因或基因网络，对于成功培育富含铁的小麦具有十分重要的意义。因此本项目以来自美国和中国381份小麦为研究材料，测定其种子中铁的含量，用全基因组关联分析和QTL相结合的方法去克隆影响铁元素在种子中积累的基因，从而解析影响种子中铁元素积累的遗传机制，为成功培育富含铁的小麦品种提供基因资源。

小麦是重要粮食作物，提高籽粒铁等营养元素含量对改善人类健康有重要意义。本项目对来自14个国家的365份小麦材料的Fe含量进行了分析，结合660K SNP 芯片的基因型数据和关联分析方法，发现71个与 Fe含量显著关联的SNP标记，预测到81个候选基因；其中4个基因同时与Zn 和 Fe含量关联，包括 NAC 和 MYB 基因。此外，针对少数显著关联位点开发了特异性分子标记，并进行了验证。