Plants produce jasmonic acid （JA） and its amino acid conjugate, jasmonoyI-L-isoleucine （JA-Ile） as major defense signals in response to wounding and herbivory. In rice （Oryza sativa）, JA and JA-Ile rapidly incre...Plants produce jasmonic acid （JA） and its amino acid conjugate, jasmonoyI-L-isoleucine （JA-Ile） as major defense signals in response to wounding and herbivory. In rice （Oryza sativa）, JA and JA-Ile rapidly increased after mechanical damage, and this increase was further amplified when the wounds were treated with oral secretions from generalist herbivore larvae, lawn armyworms （Spodoptera mauritia）, revealing for the first time active perception mechanisms of herbivore-associated elicitor（s） in rice. In the rice genome, two OsJAR genes can conjugate JA and lie and form JA-Ile in vitro; however, their function in herbivory- induced accumulation of JA-Ile has not been investigated. By functional characterization of TOS17 retrotransposon-tagged Osjarl plants and their response to simulated herbivory, we show that OsJAR1 is essential for JA-Ile production in herbivore-attacked, field-grown plants. In addition, OsJAR1 was required for normal seed development in rice under field conditions. Our results suggest that OsJAR1 possesses at least two major functions in rice defense and development that cannot be complemented by the additional OsJAR2 gene function, although this gene previously showed overlapping enzyme activity in vitro.展开更多
基金supported by the Japan Advanced Plant Science Networkthe Grant-in-Aid for Scientific Research No.24570026 provided to IG by the Japan Society for the Promotion of Science
文摘Plants produce jasmonic acid （JA） and its amino acid conjugate, jasmonoyI-L-isoleucine （JA-Ile） as major defense signals in response to wounding and herbivory. In rice （Oryza sativa）, JA and JA-Ile rapidly increased after mechanical damage, and this increase was further amplified when the wounds were treated with oral secretions from generalist herbivore larvae, lawn armyworms （Spodoptera mauritia）, revealing for the first time active perception mechanisms of herbivore-associated elicitor（s） in rice. In the rice genome, two OsJAR genes can conjugate JA and lie and form JA-Ile in vitro; however, their function in herbivory- induced accumulation of JA-Ile has not been investigated. By functional characterization of TOS17 retrotransposon-tagged Osjarl plants and their response to simulated herbivory, we show that OsJAR1 is essential for JA-Ile production in herbivore-attacked, field-grown plants. In addition, OsJAR1 was required for normal seed development in rice under field conditions. Our results suggest that OsJAR1 possesses at least two major functions in rice defense and development that cannot be complemented by the additional OsJAR2 gene function, although this gene previously showed overlapping enzyme activity in vitro.
