Matrix-free UV-laser desorption/ionization (LDI) mass spectrometric imaging at the single-cell level: distribution of secondary metabolites of Arabidopsis thaliana and Hypericum species
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Hoelscher, Dirk; Schroff, Rohit; Knop, Katrin; Gottschaldt, Michael; Crecelius, Anna; Schneider, Bernd; Heckel, David G.; Schubert, Ulrich S.; Svatos, Ales
- Abstract:
- The present paper describes matrix-free laser desorption/ionisation mass spectrometric imaging (LDI-MSI) of
highly localized UV-absorbing secondary metabolites in plant tissues at single-cell resolution. The scope and
limitations of the method are discussed with regard to plants of the genus Hypericum. Naphthodianthrones
such as hypericin and pseudohypericin are traceable in dark glands on Hypericum leaves, placenta, stamens
and styli; biflavonoids are also traceable in the pollen of this important phytomedical plant. The highest spatial
resolution achieved, 10 lm, was much higher than that achieved by commonly used matrix-assisted laser
desorption/ionization (MALDI) imaging protocols. The data from imaging experiments were supported by
independent LDI-TOF/MS analysis of cryo-sectioned, laser-microdissected and freshly cut plant material. The
results confirmed the suitability of combining laser microdissection (LMD) and LDI-TOF/MS or LDI-MSI to
analyse localized plant secondary metabolites. Furthermore, Arabidopsis thaliana was analysed to demonstrate
the feasibility of LDI-MSI for other commonly occurring compounds such as flavonoids. The organspecific
distribution of kaempferol, quercetin and isorhamnetin, and their glycosides, was imaged at the
cellular level.
- Year:
- 2009
- Type of Publication:
- Article
- Journal:
- The Plant Journal
- Volume:
- 60
- Pages:
- 907 - 918