A fluorescent alternative to the strigolactone GR24.

Plant Production, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent 9000, Belgium.
Molecular Plant (Impact Factor: 6.13). 09/2012; DOI:10.1093/mp/sss110
Source: PubMed

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, synthesised 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 analogues. 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 signalling pathway. In water methanol solutions, CISA-1 was about 3 fold more stable than GR24, which may contribute to the increased activity observed in the various biological tests.

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