Fig. 3. The localisation of the nuclear structures containing PtdIns(4,5)P₂ is cell-cycle dependent. Synchronised NIH-3T3 cells were fixed at different stages of mitosis and the distributions of DNA and PtdIns(4,5)P₂ were visualised with Hoechst 33342 (blue, A,D,G,J,M), and 2C11 antibody (red, B,E,H,K,N), respectively. Pseudo-colour merged images emphasise the lack of co-localisation between PtdIns(4,5)P₂ and DNA (merge, C,F,I,L,O). Fluorescent images were acquired with a CCD camera-equipped Zeiss microscope. Bars, 10 µm. Cells in telophase were prepared for electron microscopy and labelled with 2C11 (P). The dotted line in (P) outlines the plasma membrane (pm). Bar, 200 nm.