(±)-Jasmonic Acid-Isoleucine (Synonyms: (±)-JA-Ile)

(±)-Jasmonic acid-isoleucine (JA-Ile) is a mixture that contains two of the four possible stereoisomers of JA-Ile: (1R,2R)- and (1S,2S)-JA-Ile. JA-Ile is a plant hormone formed by the conjugation of jasmonic acid and the amino acid isoleucine.[1] JA-Ile signals through a co-receptor complex composed of the jasmonate ZIM-domain (JAZ) repressor proteins and an E1 ubiquitin ligase complex containing the F-box Coronatine Insensitive 1 (COI1).[2],[1] Activation of the COI1-JAZ complex directs the degradation of the JAZ protein, resulting in the release of transcription factors bound and inhibited by JAZ.2,1 JA-Ile contributes to several aspects of plant growth and development and levels increase under stress conditions leading to the production of defense compounds and inhibition of growth.[2],[3],[4] The (–)-JA-Ile isomer is more active than the (+)-JA-Ile isomer at inducing gene expression of jasmonate-induced protein of 23 kDa (JIP-23) in barley.[5]

Reference:
[1]. Katsir, L., Chung, H.S., Koo, A.J.K., et al. Jasmonate signaling: A conserved mechanism of hormone sensing Curr. Opin. Plant Biol. 11(4), 428-435 (2008).
[2]. Goossens, J.F., Fernández-Calvo, P., Schwizer, F., et al. Jasmonates: Signal transduction components and their roles in environmental stress responses Plant. Mol. Biol. 91(6), 673-689 (2016).
[3]. Kang, J.-H., Wang, L., Giri, A., et al. Silencing threonine deaminase and JAR4 in Nicotiana attenuata impairs jasmonic acid–isoleucine–mediated defenses against Manduca sexta Plant Cell 18(11), 3303-3320 (2006).
[4]. Koo, A.J. Metabolism of the plant hormone jasmonate: A sentinel for tissue damage and master regulator of stress response Phytochem. Rev. 17, 51-80 (2018).
[5]. Kramell, R., Miersch, O., Hause, B., et al. Amino acid conjugates of jasmonic acid induce jasmonate-responsive gene expression in barley (Hordeum vulgare L.) leaves FEBS Lett. 414(2), 197-202 (1997).