Fig. 6: A plausible model of SARS-CoV-2 replication.
From: Correlative multi-scale cryo-imaging unveils SARS-CoV-2 assembly and egress
(1) Viral genome replication occurs inside the DMVs, generating the negative-strand viral and subgenomic RNAs (red), positive vRNA genomic copy, and subgenomic mRNAs (blue). (2) Positive RNAs are exported to cytoplasm through the DMV pores. Subgenomic mRNAs are translated (2b). Structural proteins M, E, and S associate with ER and Golgi membranes. Genomic vRNA becomes complexed with newly synthetized N (2a). (3) S, E, and M are transported in dense vesicles, which are fused with SMVs. (4) Productive viral assembly happens in the SMV clustering the viral spikes and encapsidating the genome in RNPs. Viruses bud to the internal space of the SMV. (5) Egress occurs through tunnels. The complex membrane compartment (CMC) is depicted in green, which encloses both postfusion spike-containing virus particles and prefusion spike-containing virus particles. DMV double membrane vesicle, SMV single membrane vesicle, CMC complex membrane compartment, LVCV large virus-containing vesicle.
