MCA-PGR: Genetic and Genomic Approaches to Understand and Improve Maize Responses to Ozone

Pi：Elizabeth Ainsworth(伊利诺伊大学，Urbana-Champaign/USDA-ARS)Copis：Andrew Leakey和Patrick Brown(伊利诺伊大学，Urbana-Champaign)和Lauren McIntyre(佛罗里达大学)主要合作者：Thomas Brutnell(唐纳德·丹福斯植物科学中心)对流层臭氧是对农作物最具破坏性的空气污染物。今天，臭氧暴露引起的氧化应激正在使潜在的玉米产量减少高达10%，在2011年，玉米产量将达到7.646亿美元。该项目将自由空气浓缩(FACE)技术的独特能力与玉米和转录组图谱的巨大遗传资源的力量结合在一起，该技术在田间范围内提供露天臭氧的可控升高。它将通过量化田间200个自交系和100个杂交玉米品系对臭氧浓度升高的遗传变异，为作物改良提供基础。该项目将使用臭氧对玉米生长、衰老、叶片新陈代谢和生殖过程影响的高通量表型分析，以确定与产量损失相关的性状。它将通过整合自交系和杂交玉米的转录组分析和详细的生理分析，在最耐受和最敏感的品系及其杂交后代中识别支持臭氧反应的基因和基因网络。该项目将开发或选择来自耐受和敏感亲本的现有双亲种群，以确定耐臭氧的QTL和eQTL。最后，该项目将评估玉米中臭氧和生物胁迫反应基因网络之间的串扰。这项工作将解决关于氧化应激如何导致抗氧化剂和碳代谢以及激素、衰老和防御途径的转录重编程的关键机制假说。这种多方面的方法是必不可少的，因为产量的多个生理驱动因素对臭氧暴露造成的氧化应激很敏感。因此，氧化应激耐受性无疑是一个复杂的、多基因的特征。定量遗传工具的广泛应用与基因表达谱和对不同种质的生化和生理分析相结合，使发现臭氧耐受性基础的挑战首次变得容易处理。关于外展和培训，这一植物基因组研究中期研究员奖(MCA-PGR)将通过基因组学和数量遗传学培训，帮助重新配备两名职业中期植物生理学家，他们研究植物对环境变化的生理和农学反应。这一新的专业知识将使他们和他们的博士后和研究生能够利用基因组学的全部力量，通过生物信息学、定量遗传学和使用下一代测序技术的表达图谱来应对农业和生态方面的主要挑战。此外，该项目将通过当地一所中学的植物生物学课外项目和高中女生的暑期科学夏令营进行推广。在该项目中开发的花粉图像和花粉生活力数据、测序和蛋白质组学数据集将在公共储存库公开提供，如iPlant Collaborative、NCBI GEO(www.ncbi.nlm.nih.gov/geo/)和EMBLEBI Pride(http://www.ebi.ac.uk/pride/).在该项目中开发的种质将通过玉米遗传合作储备中心(http://maizecoop.cropsci.uiuc.edu/).)获得

PI: Elizabeth Ainsworth (University of Illinois, Urbana-Champaign/USDA-ARS)CoPIs: Andrew Leakey and Patrick Brown (University of Illinois, Urbana-Champaign) and Lauren McIntyre (University of Florida)Key Collaborator: Thomas Brutnell (Donald Danforth Plant Science Center)Tropospheric ozone is the most damaging air pollutant to crops. Today, oxidative stress arising from ozone exposure is reducing potential maize yields by up to 10%, which in 2011 would have been valued at $7646 million. This project couples the unique capabilities of Free Air Concentration Enrichment (FACE) technology, which provides controlled elevation of ozone in open-air at field scale, with the power of the vast genetic resources in maize and transcriptome profiling. It will provide a foundation for crop improvement by quantifying genetic variation in response to elevated ozone among 200 inbred and 100 hybrid maize lines in the field. The project will use high-throughput phenotyping of ozone impacts on maize growth, senescence, leaf metabolism and reproductive processes to identify traits that correlate with yield loss. It will identify the genes and gene networks underpinning the ozone response in the most extreme tolerant and susceptible lines, and their hybrids, by integrating transcriptome analysis and detailed physiological analysis in inbred and hybrid maize. The project will develop or select existing biparental populations derived from tolerant and sensitive parents to identify QTL and eQTL for ozone tolerance. Finally, the project will assess crosstalk between ozone and biotic stress response gene networks in maize. This work will address key mechanistic hypotheses about how oxidative stress leads to transcriptional reprogramming of antioxidant and carbon metabolism, as well as hormone, senescence and defense pathways. This multifaceted approach is essential because multiple physiological drivers of yield are sensitive to oxidative stress from ozone exposure. Consequently, oxidative stress tolerance is undoubtedly a complex, polygenic trait. The broad application of quantitative genetic tools coupled to gene expression profiling and biochemical and physiological analyses of diverse germplasm makes the challenge of discovering the foundation for ozone tolerance tractable for the first time. With regard to outreach and training, this Mid-Career Investigator Award in Plant Genome Research (MCA-PGR) will help re-tool two mid-career plant physiologists who study plant physiological and agronomic responses to environmental change with training in genomics and quantitative genetics. This new expertise will allow them and their post-docs and graduate students to address major challenges in agriculture and ecology by leveraging the full power of genomics through bioinformatics, quantitative genetics and expression profiling using next-generation sequencing technologies. In addition, the project will provide outreach through an after-school program on plant biology at a local middle school and a summer science camp for high school girls. Pollen images and pollen viability data, sequencing and proteomics datasets developed in this project will be publicly available at public repositories such as the iPlant Collaborative, NCBI GEO (www.ncbi.nlm.nih.gov/geo/), and EMBL-EBI PRIDE (http://www.ebi.ac.uk/pride/). Germplasm developed in this project will be available through the Maize Genetics Cooperation Stock Center (http://maizecoop.cropsci.uiuc.edu/).