Copper (Cu) transporter that plays an essential role in promoting translocation of Cu from roots to shoots. Involved in loading Cu to the xylem of the roots and other organs, including panicles. ATP + Cu(+)(in) + H2O = ADP + Cu(+)(out) + H(+) + phosphate Expressed in root pericycle cells, xylem region of diffuse vascular bundles in the first node, and vascular tissues of peduncle, rachis and husk. Weakly induced by high copper concentration. Reduced grain yield. Increased levels of copper in roots. Decreased levels of copper in shoots and grains. Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IB subfamily.