EAGER: Non-integrative transient delivery of reagents into plant cells via the type IV secretion system of A. tumefaciens

过去几十年通过公共部门投资开发的创新转化为极大地提高了美国农业生产率的技术，例如，通过精确地使用水、养分和杀虫剂来减少农业投入。基因技术导致了更好的植物育种预测模型，并将无法通过传统方法添加的新特征引入作物。然而，使用生物技术引入新特征的能力往往受到低效率的阻碍。该项目旨在通过利用根癌农杆菌向植物细胞分泌蛋白质的能力，提高根癌农杆菌作为工具将新特性引入农作物的效率。这些蛋白质的瞬时传递既会影响植物细胞检测和击退细菌的能力，也会影响植物细胞一旦被改变就能再生新植物的能力。为了实现这一目标，将采取多学科方法，将遗传学、微生物学和分子生物学的专业知识结合起来。重要的是，该项目的生物学基础将通过与非科学界就食品生产的各个方面以及农业创新如何通过其生产充足和安全的食品供应的能力来帮助保持战略优势的宣传工作进行交流。在这个项目中进行的研究展示了一系列创新的研究，以设计和测试新的根癌农杆菌菌株，这些菌株可以帮助减轻植物转化的两个主要低效因素：细胞接受遗传试剂的能力和同一细胞导致诱导的遗传变化的种线传播的能力。抑制植物天然免疫反应的假单胞菌效应蛋白将被瞬时表达，以提高从细菌到植物细胞的基因转移效率。此外，植物形态发生蛋白将被瞬时表达，以提高转化组织培养细胞再生植株的效率。这些研究的结果还将提供对可以穿梭于农杆菌IV型分泌系统的蛋白质大小限制的洞察。总体而言，该项目应该会导致根癌农杆菌菌株在植物物种内更广泛的基因类型上具有更强的转化能力，并且可以很容易地转移到植物科学界。该奖项反映了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。

Innovations developed through public sector investments over the past few decades have translated to technologies that have benefited U.S. agriculture productivity significantly, for example, reducing agriculture inputs through precision application of water, nutrients, and pesticides. Genetic technologies have led to better predictive models for plant breeding and introduction of novel traits into crops that could not be added by conventional means. However, the ability to introduce novel traits using biotechnology is often hampered by low efficiencies. This project seeks to improve the efficiency with which Agrobacterium tumefaciens can serve as a tool to introduce novel traits into crop plants by exploiting the bacterium's ability to secrete proteins into plant cells. The transient delivery of these proteins will impact both the ability of the plant cell to detect and fight off the bacterium, and the ability of the plant cell to regenerate a new plant once it has been altered. To meet this goal, a multidisciplinary approach will be taken that brings together expertise in genetics, microbiology and molecular biology. Importantly, the underlying biology of the project will be communicated through outreach efforts to the non-science community on all aspects of food production and on how innovations in agriculture help maintain the U. S. strategic advantage through its capacity to produce a plentiful and safe food supply. The research to be conducted in this project lays out an innovative set of studies to design and test novel Agrobacterium tumefaciens strains that can help mitigate two major inefficiencies of plant transformation: the competency of the cell to receive a genetic reagent and the ability of that same cell to lead to germline transmission of the induced genetic change. Pseudomonas effector proteins that suppress the plant innate immune response will be transiently expressed to improve the efficiency of gene transfer from bacterium to plant cell. In addition, plant morphogenic proteins will be transiently expressed to improve the efficiency of regenerating plants from transformed tissue culture cells. The results of these studies will also provide insight into the size limit of a protein that can be shuttled through the Agrobacterium type IV secretion system. Overall, this project should lead to A. tumefaciens strains with enhanced transformation capacity across a broader array of genotypes within a plant species and that are easily transferable to the plant science community.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.