Fig. 3.

Budding of SARS-CoV occurs in the ERGIC and Golgi area already at 3 h p.i. (a–d) Vero cells were mock-infected (a) or infected with SARS-CoV (MOI of 10) for 3 h (b) or 5 h (c, d), fixed and analyzed by standard EM. The nuclei are marked with “Nu” and the Golgi with “G”. Viral particles are highlighted with arrows (b–d). Scale bars represent 200 or 500 nm as indicated. (e, f) Vero cells were infected with SARS-CoV (MOI of 10) for 3 h, fixed and analyzed by cryo-iEM with antibodies directed against SARS-CoV N (10 nm gold, filled arrowheads) and β′COP-I as a marker for the ERGIC and Golgi area (15 nm gold, open arrowheads). Budding profiles are marked with small arrows, large arrows point to viral particles. Scale bars represent 100 nm.