Abstract
Plants respond to insect attack and pathogen by activating the expression of genes involved in disease resistance. In rice, jasmonic acid (JA) is assumed to play an important role as a signaling molecule in defense responses. The synthesis of linolenic acid (LA), the precursor of JA, is catalyzed by two plastidial ω-3 fatty acid desaturases which are encoded by two genes, FAD7-1 and FAD7-2. To determine the role of JA, we generated transgenic rice in which the expression of both FAD7-1 and FAD7-2 is suppressed by RNAi method. LA content in leaves of the FAD-suppressed transformant (F7Ri) was reduced to approximately 13% of the wild-type level. Wound-induced JA accumulation of the F7Ri was reduced to approximately 10% of the wild-type level. These results indicate that F7Ri line is a useful tool for studying the role of JA in rice.
