Delivering copper within plant cells

Two genes recently identified in Arabidopsis thaliana may be involved in se questering free copper ions in the cytoplasm and delivering copper to post- Golgi vesicles. The genes COPPER CHAPERONE and RESPONSIVE TO ANTAGONIST1 ar e homologous to copper-trafficking genes from yeast and humans. This plant copper-delivery pathway is required to create functional ethylene receptors . The pathway may also facilitate the transport of copper from senescing le af tissue. In addition, several other genes have been identified recently t hat may have a role in copper salvage during senescence.