1P-35 PDF
Comparative metabolite profiling of intact tomato trichomes at single-cell resolution using pressure probe electrospray ionization mass spectrometry
Trichomes are unicellular or multicellular outgrowths originating from the aerial epidermal cells of stems, leaves, floral organs and fruits. In Solanum spp., they are typically classified into eight distinct types based on their morphological appearance. Some types of trichome are known to synthesize and accumulate specialized metabolites, the content of which may vary transiently through developmental stages or depending on the growth conditions of plants. Monitoring of the physicochemical and metabolic properties of individual trichome cells is, therefore, a potential means to provide diagnostic clues for physiological status of plants. By using pressure probe electrospray ionization mass spectrometry (PPESI-MS), we demonstrated metabolite profiling in intact single cells from different types of trichome on the stems, leaves, and fruits of tomato plants. The metabolites most frequently observed were malic acid and disaccharide in negative and positive ion mode, respectively. However, the relative abundance and number of the metabolites varied among different types of trichome. Comparisons were also made between PPESI-MS mass spectra of single cells and nanoESI-MS with diluted cell sap samples to confirm the result. The type specific variations in metabolite profiles and improvements made in the PPESI-MS system will be further discussed.