Genetic and Genomic Approaches to Understanding the Role of Auxin in Shoot Development

首席研究员：Paula McSteen（密苏里大学哥伦比亚分校）首席研究员：Simon Malcomber（加州州立大学长滩分校）、Andrea Gallavotti、赵云德（加州大学圣地亚哥分校）高级研究员：Naomi Altman、Reka Albert（宾夕法尼亚州立大学）合作伙伴：Robert Schmidt（加州大学圣地亚哥分校）生长素调节着植物生长发育的方方面面，包括叶子和花的形成，茎和花序的分枝。该项目的长期目标是了解生长素生物合成、运输和信号转导途径如何调节茎（植物的地上部分）的生长，以及这些机制和相互作用在大约25万种开花植物中被保存的程度。利用玉米的高通量前向遗传学和玉米和拟南芥的比较表达谱，将鉴定和表征在生长素介导的芽发育中起作用的基因。反向遗传分析将用于揭示基因在这些途径中的功能，这些途径可能不明显，仅从正向遗传方法。基因功能将使用转基因报告系与表型、表达和特征突变的遗传分析相结合来分析，以组装遗传相互作用的网络。将建立一个基因调控网络模型，将表达谱数据与遗传和生化相互作用研究相结合。利用现有的基因组数据和在研究过程中分离的基因对已鉴定的基因家族进行系统发育表征，将为所有开花植物中生长素的保存和多样性机制提供框架和一系列可测试的假设。该项目的研究结果将有助于更好地了解生长素如何控制农艺学和经济上重要作物的生长和发育。通过一系列的培训和推广项目，该项目将为高中生、本科生、研究生和博士后研究人员提供学习和应用广泛的遗传、发育、进化、基因组、统计、数学和生物信息学工具的机会。每年的夏季研讨会和交流项目将加强跨学科的植物科学培训和跨领域的对话。该项目的成果将被纳入美国植物学会的种植科学计划（http://www.plantingscience.org/），该计划旨在为全国高中学生创建在线开放式、基于探究的教育材料，重点关注生长素的作用和植物生物学的跨学科性质。本项目的研究成果将为探究植物生长素在开花植物生长发育中的作用提供新的资源和工具，并为提高不同作物品种的作物产量提供新的信息和策略。项目数据将通过项目网站（http://www.auxinevodevo.org）提供。此外，突变体库存将从玉米鸡舍库存中心（http://maizecoop.cropsci.uiuc.edu/）获得，表型和遗传数据（包括图谱位置）将存储在MaizeGDB （http://www.maizegdb.org/）上，表达谱数据将存储在植物表达数据库（http://www.plexdb.org/）上。系统发育树将存储在TREEBASE （http://www.treebase.org）上，序列将存储在Genbank（http://www.ncbi.nlm.nih.gov/）和Plant GDB （http://www.plantgdb.org）上。

PI: Paula McSteen (University of Missouri - Columbia)CoPIs: Simon Malcomber (California State University - Long Beach), Andrea Gallavotti and Yunde Zhao (University of California - San Diego)Senior Personnel: Naomi Altman and Reka Albert (The Pennsylvania State University)Collaborator: Robert Schmidt (University of California - San Diego)The hormone auxin regulates almost every aspect of plant growth and development, including leaf and flower formation, and stem and flower cluster (inflorescence) branching. The long-term goal of this project is to understand how shoot (the above ground portion of a plant) growth is regulated through pathways of auxin biosynthesis, transport and signal transduction, and the extent to which these mechanisms and interactions are conserved among the approximately 250,000 described species of flowering plants. Genes that function in auxin mediated shoot development will be identified and characterized using a combination of high throughput forward genetics in maize and comparative expression profiling in both maize and Arabidopsis. Reverse genetic analyses will be used to uncover the function of genes in these pathways that may not be apparent from forward genetic approaches alone. Gene function will be analyzed using transgenic reporter lines coupled with phenotypic, expression and genetic analyses of characterized mutants to assemble a network of genetic interactions. A gene regulatory network model will be built to integrate the data from expression profiling together with genetic and biochemical interaction studies. Phylogenetic characterization of identified gene families using available genomic data and genes isolated during the course of the research will provide a framework and series of testable hypotheses concerning the conservation and diversification of auxin mechanisms in all flowering plants. The findings from this project will lead to a better understanding of how auxin controls shoot growth and development in agronomically and economically important crops.Through a series of training and outreach programs this project will provide opportunities for high school students, undergraduates, graduate students, and postdoctoral researchers to learn and apply a broad range of genetic, developmental, evolutionary, genomic, statistical, mathematical and bioinformatic tools. Annual summer workshops and exchange programs will augment inter-disciplinary plant science training and dialog across fields. Results from the project will be incorporated into the Botanical Society of America's Planting Science program (http://www.plantingscience.org/) to create online open-ended, inquiry-based educational materials focusing on the role of auxin and the interdisciplinary nature of plant biology for high school students across the nation. Materials from this project will provide new resources and tools to investigate the role played by auxin in plant growth and development across flowering plants, and new information and strategies for improving crop yield in diverse crop species. Project data will be made available through the project website (http://www.auxinevodevo.org). In addition, mutant stocks will be available from the Maize Coop Stock Center (http://maizecoop.cropsci.uiuc.edu/), phenotypic and genetic data including map locations will be deposited at MaizeGDB (http://www.maizegdb.org/), expression profiling data will be deposited at the Plant Expression Database (http://www.plexdb.org/), phylogenetic trees will be deposited at TREEBASE (http://www.treebase.org) and sequences will be deposited in Genbank(http://www.ncbi.nlm.nih.gov/) and Plant GDB (http://www.plantgdb.org).