Figure 1
Simplified life cycle of SARS-CoV-2. The virus enters a host’s cell and releases its genome in cytoplasm. Viral RNA is translated into two polyproteins: pp1a and pp1ab. Then, due to autocleavage, two viral proteases (PLpro and Mpro) are liberated. Their main role is to further process polyproteins, what results in a release of other nsps. Next, a group of nsps form replication and transcription complexes (RTCs). RTCs are further involved in a generation of copies of viral genomic RNA (g-RNA), as well as a set of sub-genomic RNAs (sg-RNA) responsible for synthesis of viral structural and accessory proteins. Virions are assembled in endoplasmic reticulum-Golgi intermediate compartments (ERGICs). g-RNA is coated with structural N-protein and enters the ERGIC containing M, E, and S glycoproteins. Then, the virions are released by exocytosis47,48. Inhibition of Mpro, PLpro, and N7-MTase may lead to suppression of virus replication. Protease inhibition stops the generation of nsps, while N7-MTase inhibition prevents the synthesis of stable transcripts of the viral RNA. Created with BioRender.com.
