Protein localization in electron micrographs using fluorescence nanoscopy

A complete portrait of a cell requires a detailed description of its molecular topography: proteins must be linked to particular organelles. Immunocytochemical electron microscopy can reveal locations of proteins with nanometer resolution but is limited by the quality of fixation, the paucity of antibodies and the inaccessibility of antigens. Here we describe correlative fluorescence electron microscopy for the nanoscopic localization of proteins in electron micrographs. We tagged proteins with the fluorescent proteins Citrine or tdEos and expressed them in Caenorhabditis elegans, fixed the worms and embedded them in plastic. We imaged the tagged proteins from ultrathin sections using stimulated emission depletion (STED) microscopy or photoactivated localization microscopy (PALM). Fluorescence correlated with organelles imaged in electron micrographs from the same sections. We used these methods to localize histones, a mitochondrial protein and a presynaptic dense projection protein in electron micrographs.

[1]  Stephen J. Smith,et al.  Array Tomography: A New Tool for Imaging the Molecular Architecture and Ultrastructure of Neural Circuits , 2007, Neuron.

[2]  J. Lippincott-Schwartz,et al.  Interferometric fluorescent super-resolution microscopy resolves 3D cellular ultrastructure , 2009, Proceedings of the National Academy of Sciences.

[3]  G. D.,et al.  Resin Microscopy and On-Section Immunocytochemistry , 1993, Springer Laboratory.

[4]  P. Sims,et al.  Fluorescence-integrated transmission electron microscopy images: integrating fluorescence microscopy with transmission electron microscopy. , 2007, Methods in molecular biology.

[5]  Michael J Rust,et al.  Sub-diffraction-limit imaging by stochastic optical reconstruction microscopy (STORM) , 2006, Nature Methods.

[6]  K. Mihara,et al.  Characterization of the Signal That Directs Tom20 to the Mitochondrial Outer Membrane , 2000, The Journal of cell biology.

[7]  J. Riemersma Osmium tetroxide fixation of lipids for electron microscopy. A possible reaction mechanism. , 1968, Biochimica et biophysica acta.

[8]  H. Horvitz,et al.  The Caenorhabditis elegans locus lin-15, a negative regulator of a tyrosine kinase signaling pathway, encodes two different proteins. , 1994, Genetics.

[9]  J. Yguerabide,et al.  Light-scattering submicroscopic particles as highly fluorescent analogs and their use as tracer labels in clinical and biological applications. , 1998, Analytical biochemistry.

[10]  K. McDonald,et al.  Cryopreparation methods for electron microscopy of selected model systems. , 2007, Methods in cell biology.

[11]  Lars Meyer,et al.  3D reconstruction of high‐resolution STED microscope images , 2008, Microscopy research and technique.

[12]  W. Webb,et al.  Precise nanometer localization analysis for individual fluorescent probes. , 2002, Biophysical journal.

[13]  이기수,et al.  II. , 1992 .

[14]  S. Hell,et al.  Breaking the diffraction resolution limit by stimulated emission: stimulated-emission-depletion fluorescence microscopy. , 1994, Optics letters.

[15]  S. Hell Far-Field Optical Nanoscopy , 2007, Science.

[16]  J. Lippincott-Schwartz,et al.  Imaging Intracellular Fluorescent Proteins at Nanometer Resolution , 2006, Science.

[17]  Erik M Jorgensen,et al.  Single-copy insertion of transgenes in Caenorhabditis elegans , 2008, Nature Genetics.

[18]  V. Ambros,et al.  Efficient gene transfer in C.elegans: extrachromosomal maintenance and integration of transforming sequences. , 1991, The EMBO journal.

[19]  Stefan W. Hell,et al.  Measurement of the 4Pi‐confocal point spread function proves 75 nm axial resolution , 1994 .

[20]  Philippe Rostaing,et al.  Preservation of Immunoreactivity and Fine Structure of Adult C. elegans Tissues Using High-pressure Freezing , 2004, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[21]  Roman Schmidt,et al.  Mitochondrial cristae revealed with focused light. , 2009, Nano letters.

[22]  T. Bonhoeffer,et al.  Live-cell imaging of dendritic spines by STED microscopy , 2008, Proceedings of the National Academy of Sciences.

[23]  M L Yarmush,et al.  Size and structure of antigen-antibody complexes. Electron microscopy and light scattering studies. , 1988, Biophysical journal.

[24]  C. Sheppard,et al.  Practical limits of resolution in confocal and non‐linear microscopy , 2004, Microscopy research and technique.

[25]  Michael D. Mason,et al.  Ultra-high resolution imaging by fluorescence photoactivation localization microscopy. , 2006, Biophysical journal.

[26]  L. Cauller,et al.  Reduction of background autofluorescence in brain sections following immersion in sodium borohydride , 1998, Journal of Neuroscience Methods.

[27]  A. Christiansson,et al.  Extraction of proteins and membrane lipids during low temperature embedding of biological material for electron microscopy , 1986, Journal of microscopy.

[28]  T. Kawano,et al.  Identification of Genes Involved in Synaptogenesis Using a Fluorescent Active Zone Marker in Caenorhabditis elegans , 2005, The Journal of Neuroscience.

[29]  P. Sims,et al.  Fluorescence-Integrated Transmission Electron Microscopy Images , 2007 .

[30]  M. Morphew 3D immunolocalization with plastic sections. , 2007, Methods in cell biology.

[31]  Michael W. Davidson,et al.  Photoconversion in orange and red fluorescent proteins , 2009, Nature Methods.

[32]  J. Roth,et al.  Enhancement of structural preservation and immunocytochemical staining in low temperature embedded pancreatic tissue. , 1981, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[33]  M. Chalfie GREEN FLUORESCENT PROTEIN , 1995, Photochemistry and photobiology.

[34]  S. Hell,et al.  Fluorescence microscopy with diffraction resolution barrier broken by stimulated emission. , 2000, Proceedings of the National Academy of Sciences of the United States of America.