Figure 1.

Visualization of the heterochromatin network in interphase cells: (a,b) Electron microscopic images of isolated rat thymocyte nuclei treated with 0.1% heparin/HBSS on supports; (a) 1 min; (b) 25 min (the nucleus fragment) by the method from [55]. PF fixation, uranyl acetate contrasting, tungsten oxide shadowing. (c) Human MCF7 cell, AO-DNA (after RNAse) fluorescent staining, deconvolution. (a–c) Large rosettes around nucleoli are encircled, heterochromatin clumps and “foots” inside them are arrowed, double alveoli are marked by double arrows. (d) Tissue imprint of chicken embryonic chondrocyte stained stoichiometrically for DNA; the method of image processing is described in [56]. (e) Mathematically skeletonized network of a DNA-stained chicken mesenchymal cell with overlaid dense chromocenters. (f) The relationship between the area of the dense chromocenters and the number of their network branches determined on chicken image-processed nuclei. Figure 1a,b republished from [52]. Figure 1d–f republished from [57].