centrations to wounded Butein chemical information leaves of rosette-stage 35S-jmt and WT plants and the regulation of TPI activity, nicotine and total DTG levels, for which we have the most knowledge, was analyzed. In JA-Ile treated leaves, TPI activity was completely restored to WT levels, but no effects were observed in systemic “2674416 35S-jmt leaves. JA-Ile also significantly induced nicotine levels in elicited leaves of 35S-jmt plants but these levels did not reach those detected in similarly treated WT leaves. JA, directly methylated by AtJMT activity, had in contrast no inducing effect on nicotine levels compared to the wound control in 35S-jmt plants. Differences in total DTG levels between WT and 35S-jmt diminished in elicited, but not systemic leaves, when leaves of 35Sjmt plants were treated with JA-Ile. Again, JA had also no significant effects compared to the wound control on DTG levels. JA-Ile partly restored the production of the phenylpropanoidpolyamine conjugate caffeoylputrescine: it significantly increased caffeoylputrescine concentrations in WT leaves but only slightly increased this metabolite in elicited 35S-jmt leaves. Discussion We investigated the impact of re-routing the JA pathway and increasing MeJA production on N. attenuata growth and herbivore October 2011 | Volume 6 | Issue 10 | e25925 Ecological Performance of 35S-jmt Plants resistance in its native habitat. Although not suffering from major developmental alterations, plants were more susceptible to the native herbivore community in Utah which was associated with an impaired production of direct and indirect defense compounds. This work confirms that the homeostatic control of the flux within the JA pathway and the production of JA-Ile are of central importance for the plant’s inducible defenses in nature and underlines that MeJA does not have defense signaling functions by itself. AtJMT ectopic expression does not constrain development of 35S-jmt-1 in nature In the field, the vegetative growth of N. attenuata 35S-jmt plants did not differ from that of EV plants. Appearance of the first flowers was slightly delayed but not to similar extent as previously seen in 35S-jmt Arabidopsis plants. Seed capsule production was reduced in 35S-jmt-1 when plants were grown under glasshouse conditions. Reduced seed capsule production in 35Sjmt plants could result from an exacerbated resource trade-off due to MeJA hyper-accumulation, as proposed by Cipollini et al., or from impaired self-pollination. Our results indicate that impaired self-pollination, caused by the reduction of floral style length, was likely responsible for the observed decrease in seed capsule production. Consistent with this hypothesis, the few capsules spontaneously generated in our 35Sjmt plants contained as many seeds as WT controls and handpollination of WT and 35S-jmt-1 flowers yielded equal numbers of seed capsules and seeds per capsule. Moreover, no evidence could be found for constitutively elevated levels of defense traits in N. attenuata that might result in an energetic demand and compromise seed production; to the contrary, we found that JA-inducible defenses were substantially reduced in 35S-jmt plants. Alterations in floral developmental processes, some being highly plant familyspecific, have been described in several mutants and transgenics in which various steps in JA signaling have been disrupted. October 2011 | Volume 6 | Issue 10 | e25925 Ecological Performance of 35S-jmt Plants Ectopic AtJMT expression in rice in
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