The role of jasmonates in mutualistic symbioses between plants and soil-born microorganisms

The Legume Root Nodule: From Symbiotic Nitrogen Fixation to Senescence

“…However, sucrose synthase activity, another parameter of drought stress effect, is not affected by this treatment suggesting that ABA is not the only player of nodule response to stress. Jasmonic acid (JA), another hormone involved in plant stress response (Reinbothe et al, 2009), has also been shown to be involved in the regulation of nodule functioning (Hause & Schaarschmidt, 2009). Exogenous JA treatment induces an accumulation of lipid peroxides and modifies ascorbate metabolism suggesting that JA could influence nodule senescence (Loscos et al, 2008).…”

Not to be suppressed? Rethinking the host response at a root-parasite interface

“…Defense-like responses such as activation of the phenylpropanoid pathway and enhanced flavonoid biosynthesis can stimulate the expression of nodulation genes in symbiotic rhizobacteria, leading to greater rhizobia attraction to the roots and also enhanced nodulation efficiency [42]. This induction is also observed in the presence of jasmonate suggesting that jasmonate signaling positively regulates the interaction between legume host plants and symbiotic rhizobia [42,43]. Foliar treatment of the legume Lotus japonicus with methyl jasmonate prior to inoculation with symbiotic rhizobacteria significantly repressed nodulation [44].…”

“…Foliar treatment of the legume Lotus japonicus with methyl jasmonate prior to inoculation with symbiotic rhizobacteria significantly repressed nodulation [44]. This effect could potentially be explained by disturbed signal transduction through the symbiosis pathway, rather than a consequence of induced resistance or ectopic activation of an enhanced immune response [43]. Jasmonate signaling has also been linked to regulation of carbon partitioning within roots colonised by arbuscular mycorrhizal fungi, suggesting a further role for jasmonate in broader symbiotic interactions [43].…”

“…This effect could potentially be explained by disturbed signal transduction through the symbiosis pathway, rather than a consequence of induced resistance or ectopic activation of an enhanced immune response [43]. Jasmonate signaling has also been linked to regulation of carbon partitioning within roots colonised by arbuscular mycorrhizal fungi, suggesting a further role for jasmonate in broader symbiotic interactions [43]. A requirement for an intact jasmonate signaling pathway during interactions with the plant root is not limited only to symbiotic interactions.…”

Molecular mechanisms in plant abiotic stress response

“…A phytohormone involved in the regulation of interactions between root and bacteria is JA and its conjugated form (MeJA) which cross the membrane barrier functioning as a long-distance signal (Hause & Schaarschmidt 2009). MeJA has been detected in high levels in germinating The ABA synthesis involves multiple reactions that occur in the plastid and the cytoplasm.…”