Arsenic tolerance and hyperaccumulation in Pteris vittata

砷是一种天然存在的类金属，对大多数生物体有毒，是一种已知的人类致癌物。它是世界许多地区土壤和地下水的主要污染物，并日益引起农业和卫生方面的关注。蕨类植物vittata在植物和动物中是特殊的，因为它能够耐受和积累非常高水平的砷。该项目的目标是通过发现该物种对砷的耐受性和积累所必需的基因和机制来了解这种蕨类植物是如何做到这一点的。该项目的目的之一是确定砷从土壤到植物顶部的路径，并测试先前确定的与砷相关的蛋白质（称为ACR2和ACR3）是否以及如何参与确定这条路线。第二个目标是通过组装和识别所有对砷有反应的开启或关闭的基因来发现新的砷相关基因。最后，被砷激活的单个基因将在蕨类植物中被敲除，并进行测试，看它们是否对该物种的砷耐受性也有必要。从该项目中获得的知识在消除食品和饲料作物中的砷污染方面具有巨大潜力。该项目的资金将支持三名研究生和许多本科生，他们将接受分子遗传技术、数据分析、植物培养技术和技术写作方面的培训，以协助所描述的研究。为了让公众了解这种非凡的“食砷植物”，PI接受了美国国家公共电台（NPR）的采访，并参加了当地一个科学研讨会，在那里描述了这项工作。每年夏天，PI还帮助从美国各地选出的20名精英高中学生准备参加一年一度的国际生物奥林匹克竞赛。这个项目的数据将广泛用于培训这些学生。

Arsenic is a naturally occurring metalloid that is toxic to most organisms and is a known human carcinogen. It is a major contaminant of soils and ground water in many regions of the world and an increasing agricultural and health concern. The fern Pteris vittata is exceptional among plants and animals in that it is able to tolerate and accumulate very high levels of arsenic. The goal of this project is to understand how this fern is able to do this by discovering genes and the mechanisms necessary for arsenic tolerance and accumulation in this species. One aim of the project is to determine the route arsenic travels from the soil to the top of the plant where it is sequestered and test whether and how arsenic-related proteins previously identified (called ACR2 and ACR3) are involved in determining this route. A second aim is to discover new arsenic-related genes by assembling and identifying all of the genes that turn on or off in response to arsenic. Finally, individual genes that are turned on by arsenic will be knocked-down in the fern and tested to see if they are also necessary for arsenic tolerance in this species. The knowledge gained from this project has great potential to eliminate arsenic contamination in food and feed crops. Funds for this project will support three graduate students and many undergraduate students, who will receive training in molecular genetic techniques, data analysis, plant culture techniques and technical writing in order to assist in the research described. To inform the public about this remarkable 'arsenic-eating plant', the PI has been interviewed by NPR and participates in a local science café where this work is described. Each summer the PI also helps to prepare 20 elite high school students selected from across the US for the annual International Biology Olympiad. Data from this project will be used extensively in training these students.