Expression of the cercosporin transporter, CFP, in tobacco reduces frog-eye lesion size.

The cercosporin Major Facilitator Superfamily (MFS) transporter, CFP, under the control of the CaMV 35S promoter, was introduced into the Xanthi cultivar of tobacco by Agrobacterium-mediated transformation. CFP(+) transgenic plants were physically indistinguishable from non-transgenic Xanthi and progressed normally through growth to seed set. Accumulation of CFP in the leaf membrane fraction of CFP(+ )transgenic plants was associated with decreased cercosporin phytotoxicity. Frog-eye leaf lesions on CFP(+ )transgenic plants infected with Cercospora nicotianae conidia were smaller but were similar in number to those on non-transgenic plants. We conclude that transgenic expression of CFP may have relevance for a disease control strategy in Cercospora-plant pathosystems where cercosporin is implicated in pathogen virulence.