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.
