5′ triphosphatase. Nsps14 is a N7 MTase and 3′-5′ exoribonuclease. ExoN of Nsap14 acts as an N7 MTase and attaches the 5′ cap to viral RNAs. Viral exoribonuclease enzyme proofreads the viral RNA genome, where Nsp15 is a viral endoribonuclease (PDB: 6