title: Three-dimensional approaches to the residual structure of histone-depleted HeLa cell nuclei.
abstract: Histone-depleted nuclei were prepared by high-salt extraction of interphase HeLa cell nuclei. A large amount of the nuclear DNA remained associated with a rapidly sedimenting residual nuclear structure including cytoplasmic (intermediate filament) and nuclear (matrix and lamina) proteins. Electron microscopy allowed detection in the insoluble structure of a residual nuclear envelope, nucleolar residues, and an intranuclear network whose correspondence with components of in situ fixed nuclei is discussed. Using three-dimensional electron microscopy, it is further demonstrated that the salt-insoluble structure remaining after histone depletion in 2 M NaCl is highly ordered. This is of the utmost importance when considering the roles reportedly ascribed to this structure in nuclear functions.
mesh_terms: D002466:Cell Nucleolus / Q000648:ultrastructure; D002467:Cell Nucleus / Q000032:analysis / Q000648:ultrastructure; D003201:Computers; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells / Q000032:analysis / Q000648:ultrastructure*; D006657:Histones / Q000032:analysis*; D006801:Humans; D008854:Microscopy, Electron; D008961:Models, Structural; D012260:Ribonucleases
chemical_list: D006657:Histones; D012260:Ribonucleases