Arsenic Uptake, Transport and Storage in Plants

项目1：摘要 水稻（Oryza sativa）是世界上一半以上人口的主食，代表了一种重要的膳食来源， 无机砷（As），一种非阈值的1类人类致癌物。当务之急是， 粮食As的发展，并建立机制，使作为达到和积累内 稻米是这一奋进的关键。本项目将阐明植物中砷稳态的遗传控制， 使不积累砷的植物得以发育。第一个具体目标检验了以下假设： 水稻的遗传多样性可以通过对已知的基因进行定位来降低籽粒中的砷含量， 不同的粮食砷含量。第二个目的是更普遍地询问哪些基因参与了将A转移到 第三个目标是根据信息测试限制As向芽/谷粒移动的策略 通过对水稻、拟南芥和富砷蕨类植物的研究，长期目标是 防止砷在水稻谷粒可食用部分的积累，但这项工作也可能提供信息， 基因负责运输砷和其他污染金属（类）到其他可食用的组织， 植物器官除了确定致病基因座，同步辐射X射线荧光显微分析（SXRF） 将被用于精确定位和植物中的物种，这是一种创新的方法， 成功地检查了As的种子负载。

Project 1: Abstract Rice (Oryza sativa), a staple food for over half the world's population, represents a significant dietary source of inorganic arsenic (As), a non-threshold, class 1 human carcinogen. It is imperative that strategies to reduce grain As are developed, and establishing the mechanisms that enable As to reach and accumulate within the rice grain is key to this endeavor. This project will elucidate the genetic control of As homeostasis in plants to enable the development of plants that do not accumulate As. The first specific aim tests the hypothesis that genetic diversity in rice can be exploited to lower grain As levels by mapping genes in accessions known to vary in grain As content. The second aim asks more generally what genes are involved in transferring As to the grain and the third aim tests strategies to limit the movement of As to the shoot/grain based on information gained from study of rice, Arabidopsis and the As accumulating fern Pteris vittata. The long-term goal is to prevent As accumulation in the edible portion of rice grain, but the work will also potentially provide information on genes responsible for transporting As and other contaminant metal(loid)s into the tissues of other edible plant organs. In addition to identifying the causal loci, synchrotron X-ray fluorescence microanalysis (SXRF) will be used to precisely localize and speciate As in plants, an innovative approach that has been used successfully to examine seed loading of As.