Figure 3

The D13 network structure is intimately associated with the ER. HeLa cells infected without IPTG were prepared as in Fig. 1. Sections, 750 nm in thickness, were subjected to STEM tomography. The figure displays four slices of the reconstructed tomogram slice 41, 51, 80 and 112 (Z:41, Z:51, Z:80 and Z:112). It shows the electron-dense spots (white arrows) displaying a regular pattern. Slice by slice inspection also shows that the spots are connected by thin structures, likely thin membrane tubes (white arrow head; Movie S1). The network structure is associated with, and surrounded by, the ER (black arrows). The slices are taken from the supplemental Movie S1.