Genomic Approaches to Identify Insect Resistance Genes in Poplar Trees

PI：Steven G.Ralph(北达科他州大学)合作PI：文浩(David)Dai(北达科他州州立大学)；Matias Kirst(佛罗里达大学(UF))作为久居生物，植物无法避免或逃避当地环境中的生物(如食草性昆虫和机会性病原体)和非生物(如干旱和极端温度)压力。相反，植物进化出了极其多样化的解剖结构和化学防御系统来保护自己。为了应对取食昆虫的攻击，植物部署了多种在分子水平上受到严格调控的防御机制。识别导致感兴趣性状变异的基因的最成功的方法之一是产生突变，然后对感兴趣性状的变化进行筛选。在以往的研究中，几十个突变系在杨树上进行了研究。被鉴定为对落叶昆虫的取食具有抗性。在这个项目中，将在至少10个这样的抗虫品系中鉴定出转基因基因。这些基因在调节抗虫性中的作用将通过基因敲除和过度表达研究在杨树中系统地研究。此外，突变植物将受到彻底的表型特征的影响，包括评估基因表达的全球变化以及昆虫取食性能和幼虫发育的测量。预计这些研究将为提高对取食昆虫的抵抗力的基因和途径提供新的见解。识别特定的抗虫基因将有助于未来培育改良的树木品种。这个项目将由来自三所大学的科学家、研究生和本科生组成的团队进行。学生将通过参与研究的各个方面，接受基因组学、生物信息学和生物技术方面的强化培训。北达科他州大学将开发一门新的基因组学计算机实验室课程，向本科生和研究生介绍微阵列数据的生物信息分析实践培训。这些宝贵的经验将为学生未来作为专业生物学家和教育工作者的职业生涯做好准备。该项目的长期目标是阐明多年生植物抗虫的遗传机制，并将这一知识纳入现有的树木育种计划，以更好地保护森林健康。有关该项目的结果和方案的详细说明，请访问http://www.und.edu/dept/biology/ralph/ralph.htm.所有的DNA序列将保存在基因库中，微阵列数据将通过基因表达总览(GEO；http://www.ncbi.nlm.nih.gov/projects/geo/))和PopGenIE数据库(http://www.popgenie.db.umu.se/popgenie/).)获取本研究中产生的生物资源将根据要求向公众开放。

PI: Steven G. Ralph (University of North Dakota)Co-PIs: Wenhao (David) Dai (North Dakota State University); Matias Kirst (University of Florida (UF)As sedentary organisms, plants cannot avoid or escape biotic (e.g., herbivorous insects and opportunistic pathogens) and abiotic (e.g., drought and extreme temperature) stresses in their local environment. Instead, plants have evolved an enormous diversity of anatomical structures and chemical defenses to protect themselves. In response to attack by feeding insects, plants deploy multiple defense mechanisms that are tightly regulated at the molecular level. One of the most successful approaches to identify genes responsible for variation in a trait of interest is to produce mutants that are then screened for alterations in the traits of interest. In previous studies, several dozen mutant lines in poplar trees (Populus spp.) were identified as resistant to feeding by defoliating insects. In this project, the modified gene in at least 10 of these insect resistant lines will be identified. The roles these genes play in mediating insect resistance will be systematically examined in poplar through both gene knock-down and over-expression studies. Furthermore, mutant plants will be subject to thorough phenotypic characterization that includes evaluation of global changes in gene expression and measurement of insect feeding performance and larval development. It is expected that these studies will provide new insight into the genes and pathways that enhance resistance to feeding insects. Identification of specific insect resistance genes will facilitate breeding of improved tree varieties in the future.This project will be performed by a team of scientists, graduate students and undergraduates from three universities. Students will receive intensive training in genomics, bioinformatics and biotechnology through participation in all aspects of the research. A new computer lab course in genomics will be developed at the University of North Dakota that will introduce undergraduate and graduate students to hands-on training in bioinformatic analysis of microarray data. These invaluable experiences will prepare students for future careers as professional biologists and educators. The long term goals of this project are to elucidate genetic mechanisms underlying insect resistance in perennial plants, and to incorporate this knowledge into existing tree breeding programs for better forest health. A detailed description of the results and protocols derived from this project can be viewed at http://www.und.edu/dept/biology/ralph/ralph.htm. All DNA sequences will be deposited in GenBank and microarray data will be accessible through the Gene Expression Omnibus (GEO; http://www.ncbi.nlm.nih.gov/projects/geo/) and the PopGenIE database (http://www.popgenie.db.umu.se/popgenie/). Biological resources generated in this study will be publicly available upon request.