Tailoring fluorescent strigolactones for in vivo investigations: a computational and experimental study

Abstract

Strigolactones (SLs) are a new class of plant hormones whose role has been recently defined in shoot branching, root development and architecture, and nodulation. They are also active in the rhizosphere as signalling molecules in the communication between plants, AMF (arbuscular mycorrhizal fungi) and parasitic weeds. In spite of the crucial and multifaceted biological role of SLs, the current knowledge on the SL biosynthetic pathway and the perception/transduction mechanism is still incomplete. Both genetic and molecular approaches are required to understand the molecular mechanism by which SLs regulate plant development. Our contribution to this topic is the design and synthesis of fluorescent labelled SL analogues to be used as probes for the detection in vivo of the receptor(s). Knowledge of the putative receptor structure will boost the research on analogues of the natural substrates as required for agricultural applications.

A Gold(I)‐Catalyzed Oxidative Rearrangement of Heterocycle‐Derived 1,3‐Enynes Provides an Efficient and Selective Route to Divinyl Ketones

“…As a further application of the proposed methodology, we applied the synthetic sequence to the synthesis of a class of plant hormones and their analogues, known as strigolactones. Strigolactones are of cutting‐edge interest for their well‐known effects on plants[10d], and as antitumoral agents . We then envisaged a new synthetic approach to indolyl analogues of strigolactones by exploiting the herein proposed sequence, gold‐catalyzed oxidation of enynes followed by Nazarov cyclization.…”

Design and visualization of second‐generation cyanoisoindole‐based fluorescent strigolactone analogs

“…Only a limited number of publications report on the synthesis and biological evaluation of fluorescently labeled SL analogs (Thuring et al ., ; Reizelman et al ., ; Prandi et al ., , , ; Tsuchiya et al ., ; de Saint Germain et al ., ). Nonetheless, SL research would greatly benefit from active tracers, as multiple aspects of SL perception and signal transduction remain to be understood.…”

“…The majority of the reported analogs involve the attachment of an external fluorophore to the canonical ABC‐scaffold or a similar tricyclic system (Figure b). The most common tags include dansyl, rhodamine, fluorescein and BODIPY dyes (Thuring et al ., ; Reizelman et al ., ; Prandi et al ., , ). Also, SL analogs with different aromatic moieties substituted on the basic tricyclic scaffold ( 9 ) were described, though the desired fluorescent properties were not obtained (Prandi et al ., ).…”

Shaping Small Bioactive Molecules to Untangle Their Biological Function: A Focus on Fluorescent Plant Hormones

“…Eventually, biological activity tests on Orobanche aegyptiaca seeds and preliminary observations in vivo were performed on both a plant (Arabidopsis thaliana) and an AM fungal (Gigaspora margarita) system for each different fluorescent-tagged SL-like molecule, leading to identify the most promising candidate for further imaging studies, the molecule BODIPY-EGO10 (EGO10-BP) (Prandi et al, 2014). Notably, this molecule shares the core structure with the SL analogue EGO10, which has been shown to retain good biological activity in al., 2011; 2013; 2014).…”