Fig. 5. Localization of Rec8 on chromatin loops in meiotic prophase. Nuclear spreads from mouse testicular cells were prepared by treatment of cells with 85 mM NaCl (A) or 75 mM KCl (B) before fixation in 1% paraformaldehyde with SDS, as described in Materials and Methods. The samples were immunofluorescently stained with anti-Rec8 antibody. DNA was counter-stained with propidium iodide. (C) Magnification of the region indicated in panel B. Bar, 2 µm.