大豆种子高叶黄素（Lutein）含量的QTL精细定位及相关候选基因的挖掘与分析

Lutein in soybean seed is avaluable functional factor of human health, having a broad potential in food and medical industry.By the early of 2014, there still lack the reports of lutein study, including the identification of major QTL, dynamic QTL,QTL×E interaction,related genescloning and their functional analyses.Recently, we have constructed a RIL population (N=180)from the cross of Dongnong46 (low lutein) and L-100 (high lutein) and performed the trails of the population for two years and three sites. The objectives of the coming project are to evaluate the variation of lutein content in different growth stages; to detect the major QTL and dynamic QTL associated with soyben lutein content; to determine different genetic effects of the QTLs (additive×additive, epistatic, etc.) and of by environmental interaction; to re-sequence the genomes of the two parents and identify SNP loci covered the whole genome; to fine map the lutein loci with SSR and SNP markers and make a high resolutional linkage map for lutein combined SSR and SNP markers; to isolate lutein related genes from the highly related region based on the gene data of Williams 82; to analyze the functions of the lutein candidate genes by genetic transformation to Arabidopsis and soybean; to select new breeding lines of high lutein content by MAS.The results from this study will be beneficial for breeding high value-added soybean varieties.

大豆籽粒中的叶黄素（Lutein）是对人类健康起重要作用的功能因子，在保健食品、加工业领域前景广阔。目前有关大豆叶黄素的分子遗传基础研究报道甚少，控制该性状的主效QTL、动态QTL及相关基因克隆与功能分析在国内外均未见报道。本项目拟利用稀有高叶黄素种质L-100与东农46杂交获得的F2︰5代重组自交系（RIL）群体，经2年3个地点试验，研究大豆叶黄素的动态变化规律，获得与其含量相关的主效QTL和动态QTL位点，揭示QTL与环境的互作效应；通过对亲本基因组5倍以上深度重测序，在SSR标记定位基础上对高叶黄素进行SNP精细定位，构建SSR和SNP位点整合的高精度连锁图谱。进而图位克隆调控叶黄素的关键候选基因，通过转基因明确候选基因的功能；通过分子辅助选择创制出高叶黄素含量大豆新品系。该研究对加速育成高叶黄素大豆新品种，提升我国大豆在国际市场竞争力、探明其分子遗传基础均具有重要的理论与实践意义。

大豆作为重要的油料作物和粮食作物，在世界范围内被广泛种植。大豆籽粒中存在的叶黄素是对人类健康起着积极作用的功能因子，作为一种新型保健食品添加剂，在保健食品加工上具有广阔的开发前景。但由于大豆叶黄素的相关研究报道较少，有关其分子遗传基础、主效QTL及相关基因克隆与功能分析尚属空白，且高叶黄素资源材料较稀少。本项目针对以上内容开展研究工作，获得3个与大豆高叶黄素含量紧密连锁的主效QTLs位点（R2大于10%）；明确了大豆叶黄素含量的动态变化规律，获得4个有利用价值的动态QTLs；建立了高密度物理图谱，通过整合的连锁图谱获得4个与叶黄素含量紧密连锁的分子标记；发现了叶黄素合成代谢密切相关的3个候选基因，并对其中2个候选基因进行了克隆，通过对拟南芥和大豆转基因植株的分子生物学和表型变异的分析，明确了其功能，证明了该基因能够显著提高大豆籽粒的叶黄素含量；结合表型鉴定和分子辅助选择，获得的高叶黄素大豆新品系3个和大豆新材料6个（叶黄素含量＞3.0mg/100g）。通过本项目的研究，将为优质大豆新品种选育提供理论基础和材料来源，加快优质加工保健型大豆新品种的选育进程。