Elucidating the Genetic Architecture of ProVitamin A and Vitamin E Biosynthesis in Seed

PI: Dean DellaPenna（密歇根州立大学），CoPIs: C. Robin Buell（密歇根州立大学），Edward S. Buckler（康奈尔大学/USDA-ARS）， Torbert R. Rocheford（普渡大学）主要合作者：Michael A. Gore（亚利桑那大学/USDA-ARS），闫建兵（墨西哥CIMMYT）迪克·约翰逊（伊利诺伊大学厄巴纳-香槟分校）和特蕾莎·m·富尔顿（康奈尔大学）类胡萝卜素是一组数百种不同的化合物，对视力和免疫系统功能至关重要，是新鲜和加工食品中的天然着色剂。一些类胡萝卜素（β -胡萝卜素、α -胡萝卜素和β -隐黄质）是人类饮食中主要的维生素A原化合物，而叶黄素和番茄红素等其他类胡萝卜素分别在降低黄斑变性或前列腺癌的发病率和严重程度方面发挥作用。该项目的目标是鉴定玉米中决定玉米种子中类胡萝卜素和维生素E含量和成分的基因及其最有用的变异（等位基因）。利用从模式植物拟南芥中获得的信息，将确定与类胡萝卜素和维生素E生物合成相关的玉米基因。对这些化合物在玉米种子中含量和组成的自然变化的了解将与最近公布的玉米基因组序列和玉米种子发育过程中基因表达的详细分析相结合，以确定这些基因的哪些特定等位基因对玉米种子中这些化合物的有益水平贡献最大。鉴定出的等位基因可以用于玉米育种计划，以提高这些化合物的水平，从而提高玉米食品和饲料的质量。同样的方法也将使鉴定在确定玉米中类胡萝卜素和维生素E水平方面发挥重要作用的新的和新的基因成为可能。所获得的综合信息将为作为人类主要食物和饲料来源的其他农作物中的这些维生素和其他维生素产生类似变化提供路线图。了解对人类和动物营养至关重要的农业种子作物生化性状的分子遗传基础是满足未来全球粮食和饲料需求的关键组成部分。该研究将为这两种生物化学途径的自然变异提供全面的遗传评估，并将为玉米和其他农业植物物种的其他植物代谢领域的基因组尺度综合分析提供模型。这项研究中产生的大量可公开获得的基因表达数据将提供无与伦比的资源，这将极大地影响玉米研究界。该研究将为培养下一代科学家提供一个独特的环境，通过参与研究植物遗传学，基因组学，数量遗传学和植物生物化学的高中，本科生，研究生和博士后助理。研究人员将通过有针对性地招募西班牙裔本科生参加这三所大学的研究项目，让代表性不足的群体参与植物科学研究。这种推广将包括向学龄前儿童、K-12学生和本科生提供遗传学、植物育种、生物化学、营养、食物来源及其与饮食和健康的关系等概念的教育。由于维生素缺乏症是一个普遍存在的全球健康问题，本研究的一个实际结果将是为美国和发展中国家更方便和更具成本效益的玉米标记辅助选择项目提供基础，以提高类胡萝卜素和维生素E的膳食水平。为此，该项目与CIMMYT（墨西哥）和IITA（尼日利亚）的研究人员建立了一个网络，以促进将相关成果无缝转移到针对发展中国家的积极的国际育种计划中。通过该项目产生的所有数据将在项目网站（http://www.maizegenomics.plantbiology.msu.edu）以及NCBI GEO （http://www.ncbi.nlm.nih.gov/geo/）、Short Read Archive （http://www.ncbi.nlm.nih.gov/Traces/sra/sra.cgi）、MaizeGDB （http://www.maizegdb.org/）和TAIR （http://www.arabidopsis.org/）等长期数据存储库中提供。

PI: Dean DellaPenna (Michigan State University)CoPIs: C. Robin Buell (Michigan State University), Edward S. Buckler (Cornell University/USDA-ARS), and Torbert R. Rocheford (Purdue University)Key Collaborators: Michael A. Gore (University of Arizona/USDA-ARS) and Jianbing Yan (CIMMYT, Mexico)Senior Personnel: Dick Johnson (University of Illinois at Urbana-Champaign) and Theresa M. Fulton (Cornell University)Carotenoids are a group of several hundred distinct chemical compounds that are essential for vision and immune system function and as natural colorants in fresh and processed foods. Some carotenoids (betacarotene, alpha-carotene and beta-cryptoxanthin) are the major provitamin A compounds in the human diet while others such as lutein and lycopene play a role in decreasing the incidence and severity of macular degeneration or prostate cancer, respectively. The goal of this project is to identify the genes and their most useful variants (alleles) in maize that determine the levels and compositions of carotenoids and vitamin E in maize seed. Using information obtained using the model plant Arabidopsis, maize genes corresponding to those responsible for the biosynthesis of carotenoids and vitamin E will be identified. Knowledge of the natural variation in the content and composition of these compounds in maize seed will be combined with the recently published genome sequence of maize and detailed analysis of gene expression during maize seed development to determine which specific alleles of these genes contribute the most to beneficial levels of these compounds in maize seed. The alleles identified can then be used in maize breeding programs to increase the levels of these compounds to enhance the quality of food and feed derived from maize. This same approach will also enable the identification of new and novel genes that play significant roles in determining the levels of carotenoids and vitamin E in maize. The combined information obtained will provide a road map for generating similar changes for these and other vitamins in other agricultural crops that serve as major food and feed sources for humanity. Understanding the molecular genetic basis of biochemical traits in agricultural seed crops that are essential for nutrition in humans and animals is a key component of meeting future global food and feed needs. The research will provide a comprehensive genetic assessment of natural variation in two such biochemical pathways and will serve as a model for genome scale integrative analysis of other areas of plant metabolism in maize and other agricultural plant species. The large body of publically available gene expression data generated in this study will provide an unparalleled resource that will greatly impact the maize research community. The research will provide a unique environment for educating the next generation of scientists through engagement of high school, undergraduate, and graduate students as well as postdoctoral associates in research at interfaces of plant genetics, genomics, quantitative genetics and plant biochemistry. The researchers will engage under-represented groups in plant scientific research through targeted recruitment of Hispanic undergraduates to the research programs at all three universities. This outreach will include educating preschool children, K-12 students, and undergraduates in the concepts of genetics, plant breeding, biochemistry, nutrition, food sources and their relevance to diet and health. As vitamin deficiencies are a pervasive global health issue, a practical outcome of this research will be to provide the basis for more expedient and cost effective marker-assisted selection programs in maize for enhanced dietary levels of carotenoids and vitamin E in the US and developing countries. Toward this end, the project have established a network with researchers at CIMMYT (Mexico) and IITA (Nigeria) to facilitate seamless transfer of relevant results into active international breeding programs targeting developing countries. All data generated through this project will be available at the project website (http://www.maizegenomics.plantbiology.msu.edu) and through long-term data repositories that include the NCBI GEO (http://www.ncbi.nlm.nih.gov/geo/) and Short Read Archive (http://www.ncbi.nlm.nih.gov/Traces/sra/sra.cgi), MaizeGDB (http://www.maizegdb.org/) and TAIR (http://www.arabidopsis.org/).