Effect of 5-FU Treatment on the Mutational Burden in SARS-CoV-2 viruses Lacking Nsp14 Exonuclease Activity.
The SARS-CoV-2 Nsp14 exonuclease domain (ExoN) plays a role in ensuring the accurate replication of the viral genome via its RNA proofreading activity. SARS-CoV-2 viruses lacking functional ExoN were generated and grown in the presence of the mutagen 5-FU to determine whether the loss of ExoN activity increases mutational burden.