Macromolecular Architecture in Eukaryotic Cells Visualized by Cryoelectron Tomography

• Published in: Science (American Association for the Advancement of Science) Vol. 298; no. 5596; pp. 1209 - 1213
• Main Authors: Medalia, Ohad, Weber, Igor, Frangakis, Achilleas S., Nicastro, Daniela, Gerisch, Günther, Baumeister, Wolfgang
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 08.11.2002; The American Association for the Advancement of Science
• Subjects: Actin Cytoskeleton - chemistry; Actin Cytoskeleton - metabolism; Actin Cytoskeleton - ultrastructure; Actins; Actins - ultrastructure; Animal cells; Animals; Binding Sites; Biochemistry; Cell Membrane - metabolism; Cell Membrane - ultrastructure; Cell membranes; Cell motility; Cell Movement; Cells; Cells (Biology); Cellular biology; Dictyostelium - chemistry; Dictyostelium - physiology; Dictyostelium - ultrastructure; Electrons; Endoplasmic Reticulum, Rough - ultrastructure; Environment; Eukaryotes; Eukaryotic cells; Freezing; Image Processing, Computer-Assisted; Macromolecular Substances; Microfilament Proteins - ultrastructure; Microfilaments; Molecular biology; Organelles; Organelles - ultrastructure; Peptide Hydrolases - ultrastructure; Prokaryotic cells; Proteasome Endopeptidase Complex; Proteome; Protozoan Proteins - ultrastructure; Ribosomes - ultrastructure; Structural Elements (Construction); Tomography; Tomography - methods
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1076184

Electron tomography of vitrified cells is a noninvasive three-dimensional imaging technique that opens up new vistas for exploring the supramolecular organization of the cytoplasm. We applied this technique to Dictyostelium cells, focusing on the actin cytoskeleton. In actin networks reconstructed without prior removal of membranes or extraction of soluble proteins, the cross-linking of individual microfilaments, their branching angles, and membrane attachment sites can be analyzed. At a resolution of 5 to 6 nanometers, single macromolecules with distinct shapes, such as the 26S proteasome, can be identified in an unperturbed cellular environment.