Ornithine decarboxylase gene (CaODC1) is specifically induced during TMV-mediated but salicylate-independent resistant response in hot pepper

A gene encoding putative ornithine decarboxylase (ODC) has been isolated by differential screening of a cDNA library from the resistant hot pepper (Capsicum annuum L.) inoculated with avirulent tobacco mosaic virus (TMV) pathotype P₀. In hot pepper plants, transcripts of the CaODC1 (C. annuum ODC1) gene started to accumulate at 24 h post-inoculation of TMV-P ₀ and the signal was spread systemically The transcript level of CaODC1 was increased rapidly in a hot pepper resistant to Xanthomonas campestris pv. vesicatoria (Xcv) but not in a susceptible hot pepper after inoculation. These results suggest possible role(s) for CaODC1 in plant defense against a broad range of pathogens including viruses and bacteria.