(±)-Jasmonic Acid-Isoleucine

(±)-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]

(±)-茉莉酸异亮氨酸（JA-Ile）是一种混合物，含有JA-Ile的四种可能立体异构体中的两种：（1R，2R）-和（1S，2S）-JA-Ile。JA-Ile是由茉莉酸和氨基酸异亮氨酸结合形成的植物激素[1]。JA-Ile通过一个由茉莉酸ZIM结构域（JAZ）抑制蛋白和一个含有F-box冠状病毒不敏感1（COI1）的E1泛素连接酶复合物组成的共受体复合物进行信号传导[2]，[1]。激活COI1-JAZ复合物导致JAZ蛋白的降解，从而释放被JAZ抑制的转录因子。2,1 JA-Ile对植物的生长和发育有多个方面的贡献，并且在应激条件下水平增加，导致防御化合物的产生和生长的抑制[2]，[3]，[4]。在大麦中，（-）-JA-Ile异构体比（+）-JA-Ile异构体更活跃，可以诱导茉莉酸诱导蛋白23 kDa（JIP-23）的基因表达[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).