The Role of Ubiquitin-Proteasome System in the Pathogenesis of Severe Acute Respiratory Syndrome Coronavirus-2 Disease

Figure 2

(a) In the presence of ATP, ubiquitin is activated and attached to E1; (b) ubiquitin is conjugated to E2; (c) E3 targets proteins that are intended for destruction; (d) ubiquitin is ligated to the protein substrate; (e) repeated ubiquitin ligation aims the substrate at the proteasome; (f) the 19S cap of the proteasome recognizes the substrate, which is then broken down after entering the 20S core [28].