title: Quantitative imaging of selenoprotein with multi-isotope imaging mass spectrometry (MIMS).
abstract: Multi-isotope imaging mass spectrometry (MIMS) allows high resolution quantitative imaging of protein and nucleic acid synthesis at the level of a single cell using stable isotope labels. We employed MIMS to determine the compartmental localization of selenoproteins tagged with stable isotope selenium compounds in human aortic endothelial cells (HAEC), and to compare the efficiency of labeling (to determine the ideal selenium source) from these compounds: [82Se]-selenite, [77Se]-seleno-methionine, and [76Se]-methyl-selenocysteine. We found that all three selenium sources appear to be localized in the nucleus as well as in the cytoplasm in HAEC. Seleno-methionine appears to be a better source for (seleno)protein synthesis. For MIMS detection, we compared freeze-drying to thin layer vs. thin sectioning for sample preparation. MIMS provides a unique and novel way to dissect selenoprotein synthesis in cells.
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Shiow-Shih
authors.initials: SS
authors.lastname: Tang
authors.affiliation: Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA ; National Resource for Imaging Mass Spectrometry (NRIMS), Cambridge, MA, USA.
authors.forename: Christelle
authors.initials: C
authors.lastname: Guillermier
authors.affiliation: Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA ; National Resource for Imaging Mass Spectrometry (NRIMS), Cambridge, MA, USA.
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.affiliation: Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA ; National Resource for Imaging Mass Spectrometry (NRIMS), Cambridge, MA, USA.
authors.forename: Joseph Collin
authors.initials: JC
authors.lastname: Poczatek
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Suzuki
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Loscalzo
authors.affiliation: Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA ; National Resource for Imaging Mass Spectrometry (NRIMS), Cambridge, MA, USA.
authors.forename: Claude
authors.initials: C
authors.lastname: Lechene