FIG 1.

Expression of SARS-CoV-2 nsp1 has strong negative effects on replication of alphavirus replicons and their packaging into infectious virions. (A) The schematic representation of VEEV replicons encoding GFP, Flag-GFP-nsp1, and nsp1-GFP-Flag. (B) Equal amounts of in vitro-synthesized replicon and helper RNAs were coelectroporated into BHK-21 cells, as described in Materials and Methods. Viral particles were harvested at 24 h post electroporation, and their infectious titers were determined on BHK-21 cells. (C) Images of coelectroporated cells were acquired on a Nikon Eclipse fluorescence microscope before harvesting the media. The means and SDs are presented. The statistical significance of differences was determined by one-way ANOVA with a post hoc Dunnett’s multiple-comparison test (n = 3).