4.2.3. Papain-Like Protease (PLpro)
PLpro is found in all the members of the coronavirus family. It plays a major role in the release of non-structural proteins from the N terminal part of the polyproteins 1a and 1ab .  It also acts as an antagonist towards interferon and is seen to inhibit the interferon regulatory factor 3 activation . This is important as by targeting PLpro, viral replication can be inhibited and can save the healthy cells from receiving signaling cascades from the infected cells . Drugs such as Disulfiram, Lopinavir, and Ritonavir are known clinical protease inhibitors against MERS and SARS and currently, their effectiveness towards COVID-19 is being tested in clinical trials .