The roles of membrane transporters in arsenic uptake, translocation and detoxification in plants

Arsenic (As) is one of the most toxic environmental contaminants that is ubiquitously distributed in the environment. Millions of people worldwide suffer from As poisoning due to As exposure from drinking water and dietary intake. Reducing As accumulation in food crops is of great importance for food safety and public health. Limiting As accumulation in food crops or phytoremediation of As-contaminated soil depend on a detailed understanding of As uptake and transport in plants. Plants take up and transport different As species via various membrane transporters that are localized in different tissues or cell types and with different orientations. Many of these transporters are responsible for the uptake and translocation of essential or beneficial nutrients, but can also transport As species inadvertently due to imperfect selectivity. Herein, we summarize the roles of transporters involved in the uptake, transport, accumulation and detoxification of different As species and the regulation mechanisms of these transporters in plants. Potential uses of these transporters for breeding or genetic engineering crops of low As accumulation or plants for phytoremediation are also discussed.