title: A fluorescent alternative to the synthetic strigolactone GR24.
abstract: Strigolactones have recently been implicated in both above- and below-ground developmental pathways in higher plants. To facilitate the molecular and chemical properties of strigolactones in vitro and in vivo, we have developed a fluorescent strigolactone molecule, CISA-1, synthesized via a novel method which was robust, high-yielding, and used simple starting materials. We demonstrate that CISA-1 has a broad range of known strigolactone activities and further report on an adventitious rooting assay in Arabidopsis which is a highly sensitive and rapid method for testing biological activity of strigolactone analogs. In this rooting assay and the widely used Orobanche germination assay, CISA-1 showed stronger biological activity than the commonly tested GR24. CISA-1 and GR24 were equally effective at inhibiting branching in Arabidopsis inflorescence stems. In both the branching and adventitious rooting assay, we also demonstrated that CISA-1 activity is dependent on the max strigolactone signaling pathway. In water methanol solutions, CISA-1 was about threefold more stable than GR24, which may contribute to the increased activity observed in the various biological tests.
authors.affiliation: Plant Production, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent 9000, Belgium.
authors.forename: Amanda
authors.initials: A
authors.lastname: Rasmussen
authors.forename: Thomas
authors.initials: T
authors.lastname: Heugebaert
authors.forename: Cedrick
authors.initials: C
authors.lastname: Matthys
authors.forename: Rik
authors.initials: R
authors.lastname: Van Deun
authors.forename: Francois-Didier
authors.initials: FD
authors.lastname: Boyer
authors.forename: Sofie
authors.initials: S
authors.lastname: Goormachtig
authors.forename: Christian
authors.initials: C
authors.lastname: Stevens
authors.forename: Danny
authors.initials: D
authors.lastname: Geelen
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D054833:Isoindoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D031672:Orobanche / Q000187:drug effects / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D018520:Plant Shoots / Q000254:growth & development; D013050:Spectrometry, Fluorescence
chemical_list: D029681:Arabidopsis Proteins; C584936:CISA-1 compound; D002352:Carrier Proteins; C507382:GR24 compound; D054833:Isoindoles; D007783:Lactones; C435920:MAX2 protein, Arabidopsis; D015107:4-Butyrolactone