FIG. 8.

Electron microscopic analysis. (A) Epon section of BHK-21 cell expressing the E protein and fixed at 4 h posttransfection. The E protein induces the formation of electron-dense membrane structures that are often continuous with the rough ER (arrowheads). (B to D) The same structures in thawed cryosections double labeled for E (5-nm gold; arrows) and Rab-1 (10-nm gold; arrowheads). Panels: B, an MHV-infected cell fixed at 5.30 hpi, C and D, BHK-21 cells expressing the E protein. Bars, 100 nm.