title: Secondary-ion mass spectrometry of genetically encoded targets.
abstract: Secondary ion mass spectrometry (SIMS) is generally used in imaging the isotopic composition of various materials. It is becoming increasingly popular in biology, especially for investigations of cellular metabolism. However, individual proteins are difficult to identify in SIMS, which limits the ability of this technology to study individual compartments or protein complexes. We present a method for specific protein isotopic and fluorescence labeling (SPILL), based on a novel click reaction with isotopic probes. Using this method, we added (19) F-enriched labels to different proteins, and visualized them by NanoSIMS and fluorescence microscopy. The (19) F signal allowed the precise visualization of the protein of interest, with minimal background, and enabled correlative studies of protein distribution and cellular metabolism or composition. SPILL can be applied to biological systems suitable for click chemistry, which include most cell-culture systems, as well as small model organisms.
authors.affiliation: Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen (Germany); Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen (Germany); International Max Planck Research School Molecular Biology, Göttingen (Germany).
authors.forename: Ingrid C
authors.initials: IC
authors.lastname: Vreja
authors.forename: Selda
authors.initials: S
authors.lastname: Kabatas
authors.forename: Sinem K
authors.initials: SK
authors.lastname: Saka
authors.forename: Katharina
authors.initials: K
authors.lastname: Kröhnert
authors.forename: Carmen
authors.initials: C
authors.lastname: Höschen
authors.forename: Felipe
authors.initials: F
authors.lastname: Opazo
authors.forename: Ulf
authors.initials: U
authors.lastname: Diederichsen
authors.forename: Silvio O
authors.initials: SO
authors.lastname: Rizzoli
mesh_terms: D000818:Animals; D002460:Cell Line; D057930:Click Chemistry; D006224:Cricetinae; D005456:Fluorescent Dyes / Q000737:chemistry; D005462:Fluorine Radioisotopes; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D036103:Nanotechnology; D011506:Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018629:Spectrometry, Mass, Secondary Ion
chemical_list: D005456:Fluorescent Dyes; D005462:Fluorine Radioisotopes; D011506:Proteins
keywords: click chemistry; isotopic labeling; protein engineering; secondary-ion mass spectrometry (SIMS); unnatural amino acid