Arsenic Uptake, Transport and Storage in Plants
Mary Lou Guerinot, Ph.D.
Associate Director, Toxic Metals Superfund Research Program
Professor, Biological Sciences
David E. Salt, Ph.D.
Professor and 6th Century Chair, University of Aberdeen
Rice, a staple food for over half the world's population, represents a significant dietary source of arsenic, a known cause of cancer. It is vital that strategies to reduce arsenic in rice are developed, and establishing the way that arsenic reaches and accumulates within the edible parts of the rice grain is key to this endeavor.
The long-term goal of this project is to prevent arsenic accumulation in the edible portion of the rice grain, but the work will also potentially provide information on genes responsible for transporting arsenic and other contaminant metals or metalloids into the tissues of other edible plant parts. The presence of essential or contaminant metals in living tissue is typically the result of transport proteins, which operate under tight genetic regulation. We will study how rice moves arsenic into the seeds as they develop by imaging elemental distribution under a range of exposures during grain development. We use elemental imaging techniques to map where the arsenic is within the plant, the grain, and even within individual cells, and X-ray spectroscopy to show its chemical form.
This mapping will occur using synchrotron X-ray fluorescence microanalysis to precisely locate and determine the types of arsenic in plants, an innovative approach that has been used successfully to examine the way in which arsenic accumulates in the seed of the plant. Ultimately, we aim to understand the genetic control of arsenic homeostasis in plants so that we can develop plants that do not accumulate arsenic.
How does arsenic get into our food? Why does rice accumulate arsenic?
Mary Lou Guerinot Pubmed
David Salt Pubmed