Fig. 1. PML bodies make contact with the chromatin. SK-N-SH cells were fluorescently labeled for PML protein, embedded and physically sectioned to 70 nm. (A) Fluorescence image of the 70 nm section (PML bodies in yellow). (B) Low magnification phosphorus maps were obtained by electron spectroscopic imaging (ESI). (C) Composite of the fluorescence and ESI image marking the position of PML bodies in the 70 nm section. The inset region indicates the area of the cell imaged at higher magnification. (D) High-magnification phosphorous map. (E) High-magnification nitrogen map. (F) Merge of the nitrogen and phosphorous maps. Structures comprising protein alone are blue and nucleic-acid-based structures are yellow. Arrowheads indicate protein contacts between the PML body and chromatin fibers. The arrows indicate chromatin contacts with the PML body. These chromatin contacts might be responsible for the positional stability of the body over time.