Involved in metal homeostasis. Specifically binds Cu(2+). The truncated isoform has less specificity in metal binding. Homotetramer. Expressed in flowers, leaves, stems and roots. A central prokaryotic signal-sequence-like domain may be used to export the protein to the chloroplast envelope after import into the stroma. Knockout lines indicate that CUTA is not essential for copper tolerance or accumulation. Belongs to the CutA family.