Figure 3.

Studying intracellular distribution of spike protein by immunocytochemistry and confocal microscopy. Cells were either infected with SARS-CoV-2 (left column) or transfected with plasmids encoding S, E, M and/or N proteins as indicated at the top. GM130 (green) was used as a cis-Golgi marker. Note that S protein (red in the top panels or white in the bottom panels) are exported on the plasma membrane when expressed alone or with N protein, but it retains into intracellular vesicles when coexpressed with M or E proteins. Images from Boson et al. [36].