SARS-CoV-2 Main Protease Suppresses Innate Immunity By Cleaving Proteins Required For Interferon Induction And Inflammation

Forbes – Many viruses rely on proteases to process polypeptides into smaller proteins required for replication and virus production. SARS-CoV-2 is no exception. It contains two proteases in the long open reading frame of ORF1A1B that encode for 15 proteins which need proteolytic processing. Main protease, or Mpro, is the cysteine protease responsible for most of these cleavages. A series of previous studies have shown that this target site for Paxlovid plays an additional role in the virus life cycle: suppression of the innate immune system. In a previous publication we described how SARS-CoV-2 is a master at suppressing the innate immune system—both through poly-functional proteins, proteins serve both more than one function in the virus life cycle, as well as a series of accessory genes which primarily alter innate immunity. Here we discuss studies on main protease (Mpro), and its activities.