Electron microscopy of cells infected with vG7Li in the presence or absence of IPTG. BS-C-1 cells were infected with vG7Li in the presence (A) or absence (B to D) of 50 μM IPTG. After 24 h, the cells were fixed and prepared for transmission electron microscopy. The arrow in panel B points to electron-dense viroplasm, which is separated from IV membranes. Arrows in panel D point to cross-sections of tubules in which the membrane bilayer is clearly discerned. Electron micrographs are shown, with the scale indicated by the bars. Abbreviations: C, crescents; nu, nucleoid within an IV.