title: Molecular basis for the direct inhibition of AP-1 DNA binding by 15-deoxy-Delta 12,14-prostaglandin J2.
abstract: Cyclopentenone prostaglandins may interfere with cellular functions by multiple mechanisms. The cyclopentenone 15-deoxy-Delta 12,14-prostaglandin J2 (15d-PGJ2) has been reported to inhibit the activity of the transcription factor AP-1 in several experimental settings. We have explored the possibility of a direct interaction of 15d-PGJ2 with AP-1 proteins. Here we show that 15d-PGJ2 covalently modifies c-Jun and directly inhibits the DNA binding activity of AP-1. The modification of c-Jun occurs both in vitro and in intact cells as detected by labeling with biotinylated 15d-PGJ2 and mass spectrometry analysis. Attachment of the cyclopentenone prostaglandin occurs at cysteine 269, which is located in the c-Jun DNA binding domain. In addition, 15d-PGJ2 can promote the oligomerization of a fraction of c-Jun through the formation of intermolecular disulfide bonds or 15d-PGJ2-bonded dimers. Our results identify a novel site of interaction of 15d-PGJ2 with the AP-1 activation pathway that may contribute to the complex effects of cyclopentenone prostaglandins on the cellular response to pro-inflammatory agents. They also show the first evidence for the induction of protein cross-linking by 15d-PGJ2.
authors.affiliation: Departamento de Estructura y Función de Proteínas, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain. dperezsala@cib.csic.es
authors.forename: Dolores
authors.initials: D
authors.lastname: Pérez-Sala
authors.forename: Eva
authors.initials: E
authors.lastname: Cernuda-Morollón
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Cañada
mesh_terms: D001665:Binding Sites; D003545:Cysteine; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors; D019281:Dimerization; D004220:Disulfides; D006801:Humans; D015230:Prostaglandin D2 / Q000031:analogs & derivatives* / Q000502:physiology*; D011485:Protein Binding; D016755:Proto-Oncogene Proteins c-jun / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: C097240:15-deoxy-delta(12,14)-prostaglandin J2; D004268:DNA-Binding Proteins; D004220:Disulfides; D016755:Proto-Oncogene Proteins c-jun; D018808:Transcription Factor AP-1; D004247:DNA; D003545:Cysteine; D015230:Prostaglandin D2