title: Development and Application of a High-Resolution Imaging Mass Spectrometer for the Study of Plant Tissues.
abstract: Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) or imaging mass spectrometry (imaging MS) has been a powerful tool to map the spatial distribution of molecules on the surface of biological materials. This technique has frequently been applied to animal tissue slices for the purpose of mapping proteins, peptides, lipids, sugars or small metabolites to find disease-specific biomarkers or to study drug metabolism. Recently, it has also been applied to intact plant tissues or thin slices thereof using commercial mass spectrometers. The present work is concerned with the refinement of MALDI/laser desorption/ionization (LDI)-Fourier transform ion cyclotron resonance (FTICR)-MS incorporating certain specific features namely, ultra-high mass resolution (>100,000), ultra-high molecular mass accuracy (<1 p.p.m.) and high spatial resolution (<10 µm) for imaging MS of plant tissues. Employing an in-house built mass spectrometer, the imaging MS analysis of intact Arabidopsis thaliana tissues, namely etiolated seedlings and roots of seedlings, glued to a small transparent ITO (indium tin oxide)-coated conductive glass was performed. A matrix substance was applied to the vacuum-dried intact tissues by sublimation prior to the imaging MS analysis. The images of various small metabolites representing their two-dimensional distribution on the dried intact tissues were obtained with or without different matrix substances. The effects of MALDI matrices on the ionization of small metabolites during imaging MS acquisition are discussed.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8568 Japan takahashi-k@aist.go.jp.
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Kyoto University, Kyoto, 606-8502 Japan Hiroshima University, Hiroshima, 739-8526 Japan These authors contributed equally to this work.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kozuka
authors.affiliation: Kobe University, Kobe, 657-8501 Japan These authors contributed equally to this work.
authors.forename: Aya
authors.initials: A
authors.lastname: Anegawa
authors.affiliation: Kyoto University, Kyoto, 606-8502 Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Nagatani
authors.affiliation: Kobe University, Kobe, 657-8501 Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Mimura
mesh_terms: D017360:Arabidopsis / Q000737:chemistry* / Q000648:ultrastructure; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D018517:Plant Roots / Q000737:chemistry / Q000648:ultrastructure; D015203:Reproducibility of Results; D036226:Seedlings / Q000737:chemistry* / Q000648:ultrastructure; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation* / Q000379:methods*; D014280:Triglycerides / Q000378:metabolism
chemical_list: D014280:Triglycerides
keywords: FTMS; Imaging mass spectrometry; LDI; MALDI; Plant tissue; Small metabolites