Approach to engineer tomato by expression of AtHMA4 to enhance Zn in the aerial parts.

The aim of this work was to assess the potential for using AtHMA4 to engineer enhanced efficiency of Zn translocation to shoots, and to increase the Zn concentration in aerial tissues of tomato. AtHMA4, a P1B-ATPase, encodes a Zn export protein known to be involved in the control of Zn root-to-shoot translocation. In this work, 35S::AtHMA4 was expressed in tomato (Lycopersicon esculentum var.

Expression of HvHMA2 in tobacco modifies Zn-Fe-Cd homeostasis.

HvHMA2 is a plasma membrane P1B-ATPase from barley that functions in Zn/Cd root-to-shoot transport. To assess the usefulness of HvHMA2 for modifying the metal content in aerial plant parts, it was expressed in tobacco under the CaMV35S promoter. Transformation with HvHMA2 did not produce one unique pattern of Zn and Cd accumulation; instead it depended on external metal supply.