A previous large-scale proteomics study in Arabidopsis also found OPT3 at the plasma membrane

We present evidence suggesting that this Cd over-accumulation may be the result of an enhanced transport of Cd through the plant, making opt3-2 a suitable background for studying long-distance transport of non-essential heavy metals. We further show that OPT3 is targeted to the plasma membrane and is preferentially expressed in the phloem. The Fe/Zn/Mn uptake transporter …