Colocalizations of tubulin with VP1 of pseudocapsids (Aa to Ad) and virions (Ae to Ah and B). Sections of NIH 3T6 fibroblasts (A) and NMuMG (B) cells fixed 20 min p.i. (Aa and Ba) or 3 h p.i. (Ab to Ah and Bb to Bd) were visualized by confocal microscopy. Staining was done with the rabbit anti-polyomavirus virion serum followed by the Alexa Fluor 488-goat anti-rabbit IgG antibody (green) and with the mouse anti-- and anti--tubulin antibody followed by the Cy3-sheep anti-mouse IgG antibody (red). Bars: 5 µm.