NSF Postdoctoral Fellowship in Biology: Identifying Mechanisms of Plant Symbiosis Control Through Virus Induced Mutant Stacking (VIMS)

埃文·埃里森博士的这项研究和培训计划的标题是“通过病毒诱导突变堆积(VIMS)识别植物共生控制的机制”。该奖学金的主办机构是剑桥大学，赞助科学家是Giles E.D.Oldroy教授。为了在不断增长的全球人口中维持和扩大粮食生产，必须开发下一代作物品种，这些品种必须利用自然系统来改善养分获取，而不是过度使用无机养分。幸运的是，大多数作物物种可以通过与有益的土壤真菌共生关系，极大地提高它们获取和利用必要养分的能力。然而，如果土壤中施入了高浓度的氮或磷，这种共生就会受到限制，从而限制了其效用。这项研究的目的是描述在高营养条件下调节共生的未知信号，从而确定在保持高生产率的同时使用较少投入的作物基因型。该项目还寻求民主化，并消除大规模基因组编辑项目的财务、地理和时间限制，这对国际分子植物改进至关重要。该项目产生的更广泛影响包括为植物科学界产生遗传和技术资源，教育对基因编辑如何有助于减少化肥使用感兴趣的公民科学家，以及将成果转化为作物改良和可持续粮食生产。培训目标包括在应用遗传和基因组工具解决重要的生物学问题方面获得实践经验。分根实验表明，丛枝菌根共生的营养抑制除了局部机制外，还存在着许多未知的系统过程。分泌肽已被证明是系统共生调节和营养反应的关键组成部分。这项研究将表征调节与菌根真菌共生的系统多肽，以响应不同的营养条件。将多种环境条件与它们的信号响应联系起来，将通过开发一种新的病毒诱导突变堆积的方法来实现，以在整个种群中快速堆积靶向突变。这一新的遗传筛选技术将被应用于创建多肽突变的组合种群，并分离能够在营养抑制条件下共生的遗传背景。在该项目期间产生的突变种群和基因工程试剂将立即提供给研究人员进行独立研究。这项研究开发的新技术可用于研究复杂的、集成的、表型反应，同时为共生的系统调控提供有价值的见解。使用这种方法确定的因果等位基因可以迅速被纳入到与农业相关的物种中，以快速改良作物。所有的数据、遗传和分子资源，以及方法学上的进步，都将通过公共长期资源库免费提供给普通科学界，并根据要求提供。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The title of the research and training plan for this fellowship to Dr. Evan Ellison is “Identifying Mechanisms of Plant Symbiosis Control Through Virus Induced Mutant Stacking (VIMS)”. The host institution for the fellowship is the University of Cambridge and the sponsoring scientist is Prof. Giles E.D. Oldroyd.To sustain and expand food production in a growing global population, next generation crop varieties must be developed that take advantage of natural systems to improve nutrient capture rather than rely on excessive application of inorganic nutrients. Fortunately, most crop species can greatly improve their ability to capture and use essential nutrients through symbiotic relationships with beneficial soil fungi. This symbiosis, however, is restricted if high concentrations of nitrogen or phosphorus have been applied to the soil, limiting the utility. The goal of this research is to characterize unknown signals that regulate symbiosis under high nutrient conditions; thereby identifying crop genotypes that use less input while maintaining high productivity. This project also seeks to democratize and remove financial, geographic and time limitations of large-scale genome editing projects, which is critical for international molecular plant improvement. Broader impacts from this project include generating genetic and technological resources for the plant science community, educating citizen scientists interested in how gene editing contributes to reducing fertilizer use, and translating results for crop improvement and sustainable food production. Training objectives include obtaining hands-on expertise in applying genetic and genomic tools to address biologically important questions. Split root experiments suggest that nutrient suppression of arbuscular mycorrhizal symbiosis exists through largely unknown systemic process in addition to local mechanisms. Secreted peptides have been demonstrated to be a critical component of systemic symbiosis regulation and nutrient response. This research will characterize systemic peptides that regulate symbiosis with mycorrhizal fungi in response to differential nutrient conditions. Connecting multiple environmental conditions to their signaling response will be accomplished by developing a new method of Viral Induced Mutant Stacking to rapidly stack targeted mutations across a population. This novel genetic screening technique will be applied to create a combinatorial population of peptide mutants and isolate genetic backgrounds enabling symbiosis under nutrient suppressive conditions. Mutant populations and genetic engineering reagents generated during this project will be immediately available to researchers for independent investigations. New technology developed in this research can be used to study complex, integrated, phenotypic responses while providing valuable insight into the systemic regulation of symbiosis. Causal alleles identified using this approach can quickly be incorporated into agriculturally relevant species for rapid crop improvement. All data, genetic and molecular resources, and methodological advances will be made freely available to the general scientific community through public long-term repositories and upon request.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.