Revisiting the mechanisms of arsenic uptake, transport and detoxification in plants

Arsenic (As) contamination leading to toxicity in animals and humans has become a major concern in the last few decades. Chronic exposure to As occurs either through contaminated drinking water or food chain. Introduction of As in the food chain takes place by its excessive uptake from soil by plants due to the irrigation with As contaminated water. The major source of human exposure to As is through consumption of As-accumulating crops and vegetables. Arsenic taken up by the plants is translocated and accumulated in the edible plant parts making it a serious worldwide concern to take necessary steps. Developing plants with reduced As levels in their edible parts is the most plausible strategy for decreasing human As intake, which requires understanding the mechanism of As uptake from soil and its transport to the above ground tissues of plants. The present review sums up the recent progress made in understanding the As uptake, translocation and detoxification mechanisms in plants, underlining the role of transporters involved in these processes. Therefore, the expressions of the candidate genes for As uptake, translocation and detoxification has been analyzed under different developmental stages and tissues of model plant rice from publicly available microarray data. The review also summarized the biotechnological approaches for manipulation of As uptake, transport and tolerance associated genes to enhance As tolerance in different plant species. Overall, the review provides a comprehensive understanding of the potential strategies for lower As accumulation in plants to eliminate the As toxicity in human.