“…In this work we stress the fact that besides the replicative and structural proteins, all of which are critical for the viral cycle, other proteins also have vital functions, and thus would constitute excellent targets for drug discovery. The helicase (nsp13), and methyl-transferases N7-Mtase (nsp14) and 2′-O-MTase (nsp16) contribute to genome stability through their involvement in the capping process; the ExoN (nsp14) is responsible for proofreading, and thus for the extremely low mutation rate and nucleoside analogs resistanse of SARS-CoV-2; several nsp3 domains, such as SUD, NAB and Ub1 are known to bind ssRNA; the NendoU (nsp15) cleaves polyuridines produced during the priming of the poly(A) ssRNA during replication, which helps to dampen dsRNA MDA5-dependent antiviral IFN responses [125]; nsp9 acts as a hub that binds ssRNA and interacts with nsp8, the N protein, and several host nuclear pore proteins [15,130,131]; the ADRP and PL pro attenuate the effects of IFN and cytokine signaling components that induce antiviral and inflammatory responses [54,142]; orf3a and orf7a induce NFB, IL-8, and JNK, promoting inflammatory responses [198], while orf3a also induces the production of fibrinogen, promoting fibrosis, one of the complications of COVID-19 [197]; orf9b is involved in suppressing mitochondrial mediated IFN antiviral responses [210]; orf6 is known to increase the lethality in CoVs by enhancing viral replication and inhibiting IFN signaling [220,223]. In CoVs, a delayed IFN response is a redundant pattern that allows robust viral replication, and also induces the accumulation of cytokine-producing macrophages, thus increasing the severity of the disease [228].…”