Biochemistry, Biophysics, and Structural Biology Commons^™

Elcs In Ice: Cryo-Electron Microscopy Of Nuclear Envelope Limited Chromatin Sheets, Mikhail Eltsov, Sergey Sosnovksi, Ada L. Olins, Donald E. Olins

Pharmaceutical Sciences Faculty Posters

Nuclear Envelope-Limited Chromatin Sheets (ELCS) form during excessive interphase nuclear envelope growth in a variety of cells. ELCS appear as extended sheets within the cytoplasm connecting distant nuclear lobes. Cross-section stained images of ELCS, viewed by transmission electron microscopy, resemble a sandwich of apposed nuclear envelopes separated by ~30 nm, containing a layer of ordered chromatin fibers. EM Procedures: The ultrastructure of ELCS was compared by three different methods: 1) aldehyde fixation/dehydration/plastic embedding/sectioning and staining; 2) high-pressure freezing/freeze substitution into plastic/sectioning and staining; 3) high-pressure freezing/cryo-sectioning/cryo-electron microscopy. Human leukemic (HL-60/S4) cells were treated with retinoic acid (4 days) to induce …