Development of New Genetic Resources for Auxin Biology

在过去的60年里，生理学研究表明植物激素吲哚-3-乙酸（IAA或生长素）几乎在植物发育的各个方面都有调节作用。生长素在分生组织和幼嫩器官中合成，通过专门的运输系统在植物中运输，并最终产生特定的细胞反应。由于激素在所有高等植物物种中发挥作用，因此对生长素稳态和反应的深入了解将影响农业的各个方面。质量，如身高，芽和根结构，芽强度，种子和果实的大小，果实成熟，衰老程序都是由生长素部分调节，并可能是定向工程的目标。先前的研究已经证明了在生长素生物学的大多数领域中存在高水平的遗传和生化冗余。由于这个原因，重要的是要研究一个模式植物系统，如拟南芥，是经得起高通量的生化和分子遗传技术。这个“概念证明”奖将支持生长素生物学的综合分析，包括生物化学，遗传和分子策略。该项目的主要目标是开发新的高通量基因筛选功能的生长素稳态，运输和反应的基因。将进行三次筛选。1)改进的分析技术将与机器人系统一起使用，以筛选大量的化学诱变拟南芥幼苗的IAA水平的变化。2)将进行大规模的激活标记筛选在生长素生物学的各个方面受到影响的突变体。3)在大肠杆菌中进行生长素代谢相关基因的功能筛选。coli细胞。这些筛选是广泛的，预计将恢复不同的突变体集合。突变体将进行详细的生长素代谢和反应的生化分析和基因功能的分子研究。该项目的结果将为生长素生物学的全面功能基因组学研究奠定基础。

During the last 60 years, physiological studies have implicated the plant hormone indole-3-acetic acid (IAA or auxin) in the regulation of virtually every aspect of plant development. Auxin is synthesized in meristems and young organs, transported through the plant by a dedicated transport system and ultimately produces a specific cellular response. Since the hormone functions in all higher plant species, a thorough understanding of auxin homeostasis and response will impact all aspects of agriculture. Qualities such as stature, shoot and root architecture, shoot strength, seed and fruit size, fruit ripening, and the senescence program are all regulated in part by auxin and may be targets for directed engineering. Previous studies have demonstrated a high level of genetic and biochemical redundancy in most areas of auxin biology. For this reason it is important to study a model plant system such as Arabidopsis that is amenable to high-throughput biochemical and molecular genetic techniques. This "proof of concept" award will support an integrated analysis of auxin biology that will include biochemical, genetic, and molecular strategies. The primary goal of the project is to develop novel high throughput genetic screens for genes that function in auxin homeostasis, transport, and response. Three screens will be conducted. 1) Improved analytical techniques will be utilized together with robotic systems, to screen large numbers of chemically mutagenized Arabidopsis seedlings for changes in IAA levels. 2) Large-scale activation-tagging screens for mutants affected in all aspects of auxin biology will be conducted. 3) A functional screen for genes involved in auxin metabolism will be conducted in E. coli cells. These screens are broad and are expected to recover a diverse collection of mutants. The mutants will be subjected to detailed biochemical analysis of auxin metabolism and response and molecular studies of gene function. The results of the project will establish the groundwork for a comprehensive functional genomics study of auxin biology.