Figure 4.

TRIM28 and TRIM33 as proviral factors for SARS-CoV-2 infection

(A) qPCR analysis of viral RNA.

(B) Western blot analysis of the viral nucleoprotein (N). The expression of the viral protein was evaluated by the band intensity of N, normalized to that of GAPDH. Cell lysates and culture supernatants were harvested 3 days post-infection.

(C) qPCR analysis of viral RNA in A549-hACE2 cells overexpressing TRIM28 or TRIM33.

(D) Western blot analysis of the viral N. The expression of the viral protein was evaluated by the band intensity of N, normalized to that of GAPDH. Cells were infected at an MOI of 1.0 the day after transfection with expression plasmids and harvested 3 days later.

(E) Subcellular localization of the S protein in infected cells. Cells were inoculated at an MOI of 2.0 and fixed the following day. Cells were stained with anti-S antibody and anti-ERGIC53. Bar, 10 μm.

(F) Electron microscopic analysis of virus particle formation in infected cells. Bar, 5.0 μm. Data are presented as the mean ± SD of three independent experiments. Statistical analysis was performed using the Dunnett test. ∗, p < 0.05; ∗∗, p < 0.01; ∗∗∗, p < 0.001.