Heavy metals like Mn and Cu, though essential for normal plant growth and development, can be toxic when present in excess in the environment. For normal plant growth maintenance of metal homeostasis is important. Excess uptake of redox active elements causes oxidative destruction. Thus, uptake, transport and distribution within the plant must be strongly controlled. Regulation includes precisely targeted transport from the macro-level of the tissue to the micro-level of the cell and organelles. Membrane transport systems play very important roles in metal trafficking. This review provides a broad overview of the long distance and cellular transport as well as detoxification and homeostasis mechanisms of Mn and Cu, which are essential micronutrients but extremely toxic at elevated concentrations.
copper; heavy metals; manganese; phytoremediation; transport
