A BRIEF REVIEW OF ARSENIC UPTAKE AND METABOLISM IN PLANTS
Arsenic is widely distributed in the environment; it is a nonessential element to plants. Excessive accumulation of arsenic can cause phytotoxieity and pose a potential health risk to humans through consumption of high-As food crops. Arsenate is taken up by plant roots via phosphate transporters, and arsenite and undissociated methylated As species (MMA and DMA) through the nodulin 26-like intrinsic protein (NIP) aquaporin channels and by a silicon efflux carrier. Arsenate is readily reduced to arsenite in planta, which is complexed with thiol-rich peptides such as phytochelatins (PCs) or effluxed to the external medium as arsenite. Arsenic is detoxified by complexation of araenite with PCs and subsequent storage in the vacuoles.Whether plants can methylate inorganic arsenic remains to be confirmed. Recent progress in the understanding of the mechanisms of arsenic uptake and metabolism in plants is reviewed in this article.
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万方数据
维普
