Emerging roles in plant defense for cis-jasmone-induced cytochrome P450 CYP81D11.

cis-Jasmone is a volatile organic compound emitted constitutively by flowers or leaves of several plant species where it acts as an attractant for pollinators and as a chemical cue for host localisation (or avoidance) for insects. ( 1-3) It is also released by some plant species after feeding damage inflicted by herbivorous insects and in this case might serve as a chemical cue for parasitoids to guide them to their prey (so called "indirect defense"). ( 4,5) Moreover, we have recently shown that plants can perceive cis-jasmone and that it acts as a signaling molecule in A. thaliana, inducing a discrete and distinctive suite of genes, of which a large subset is putatively involved in metabolism and defense responses. ( 6) Cytochrome P450s feature prominently in these functional subsets and of these the highest fold change upon cis-jasmone treatment occurred with the cytochrome CYP81D11 (At3g28740). ( 6) Hence this gene was chosen for a more thorough analysis of the potential biological relevance of the cis-jasmone induced defense response. Although the precise function of CYP81D11 remains to be determined, we could previously demonstrate its involvement in the indirect defense response in Arabidopsis, as plants exposed to cis-jasmone ceased to be attractive to the aphid parasitoid Aphidius ervi when this P450 was inactivated by T-DNA insertion mutagenesis. ( 6) Here we report additional experiments which give further support to a role of CYP81D11 in the direct or indirect defense response of A. thaliana.