Identification of a copper chaperone from tomato fruits infected with Botrytis cinerea by differential display.

Differential display was used to isolate tomato genes responding to fungal infection. Here we describe the isolation and characterization of a gene that is down-regulated in tomato fruits infected with the phytopathogen Botrytis cinerea. The cDNA identified encodes a protein that shares sequence similarity to the amino terminal region of CCH, a copper chaperone from Arabidopsis thaliana, that participates in intracellular copper homeostasis by delivering Cu to the secretory pathway. The fact that this newly characterized tomato gene, referred to as LeCCH (Lycopersicon esculentum copper chaperone), be differentially expressed after fungal infection, suggests an interesting relationship between copper homeostasis and plant defense responses. LeCCH contains the conserved metal-binding domain MXCXGC but interestingly, lacks the C-terminal extension present in previously described plant members of this copper chaperone family, that seems to be involved in metallochaperone intercellular transport. This fact indicates that LeCCH is a novel plant copper chaperone that could act locally at the infection site, affecting the copper homeostasis in this particular stress situation.