Synonyms: a JA-Ile, a jasmonate-isoleucine, a jasmonic acid-isoleucine, a jasmonic acid-isoleucine conjugate, a jasmonyl isoleucine
|Superclasses:||a hormone → a plant hormone → a jasmonate|
Jasmonoyl-isoleucine (JA-Ile) has been detected in Arabidopsis thaliana [Staswick04] and a number of other plant species [Tamogami08, Sembdner93, Wang07c]. There are two different naturally occurring stereoisomers of this compound, (-)-jasmonoyl-L-isoleucine and (+)-7-iso-jasmonoyl-L-isoleucine, that can spontaneously interconvert through epimerization [Fonseca09].
In Arabidopsis thaliana, JA-Ile promotes binding between the COI1 F-box protein and the JAZ1 repressor involved in jasmonic acid-mediated signaling [Thines07]. Therefore, JA-Ile promotes the degradation of JAZ1. Initial studies suggested that (-)-JA-Ile was a biologically active phytohormone [Sembdner93, Guranowski07]. However, later work shows that (+)-7-iso-jasmonoyl-L-isoleucine is the biologically active form of the compound [Fonseca09]. This compound exists at low levels in most commercial preparations of (-)-jasmonoyl-L-isoleucine and may explain the observed biological activity originally associated with (-)-JA-Ile. A pure preparation of that stereoisomer does not promote JAZ/COI1 binding in vitro [Fonseca09].
Chemical Formula: C18H29NO4
Monoisotopic Molecular Weight: 323.2096584245 Daltons
Standard Gibbs Free Energy of Formation (ΔfG'° in kcal/mol): 207.59248 [Latendresse13]
Reactions known to produce the compound:
Fonseca09: Fonseca S, Chini A, Hamberg M, Adie B, Porzel A, Kramell R, Miersch O, Wasternack C, Solano R (2009). "(+)-7-iso-Jasmonoyl-L-isoleucine is the endogenous bioactive jasmonate." Nat Chem Biol 5(5);344-50. PMID: 19349968
Guranowski07: Guranowski A, Miersch O, Staswick PE, Suza W, Wasternack C (2007). "Substrate specificity and products of side-reactions catalyzed by jasmonate:amino acid synthetase (JAR1)." FEBS Lett 581(5);815-20. PMID: 17291501
Kang06: Kang JH, Wang L, Giri A, Baldwin IT (2006). "Silencing threonine deaminase and JAR4 in Nicotiana attenuata impairs jasmonic acid-isoleucine-mediated defenses against Manduca sexta." Plant Cell 18(11);3303-20. PMID: 17085687
Sembdner93: Sembdner, G., Parthier, B. (1993). "The Biochemistry and the Physiological and Molecular Actions of Jasmonates." Annual Review of Plant Physiology and Plant Molecular Biology. 44: 569-589.
Tamogami08: Tamogami S, Rakwal R, Agrawal GK (2008). "Interplant communication: airborne methyl jasmonate is essentially converted into JA and JA-Ile activating jasmonate signaling pathway and VOCs emission." Biochem Biophys Res Commun 376(4);723-7. PMID: 18812165
Thines07: Thines B, Katsir L, Melotto M, Niu Y, Mandaokar A, Liu G, Nomura K, He SY, Howe GA, Browse J (2007). "JAZ repressor proteins are targets of the SCF(COI1) complex during jasmonate signalling." Nature 448(7154);661-5. PMID: 17637677
Wang07c: Wang L, Halitschke R, Kang JH, Berg A, Harnisch F, Baldwin IT (2007). "Independently silencing two JAR family members impairs levels of trypsin proteinase inhibitors but not nicotine." Planta 226(1);159-67. PMID: 17273867
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