Inhibits host IFN-beta production. Plays a role in the degradation of the host transcriptional activator CREBBP protein. The degradation of host CREBBP which is a key component of the IFN enhanceosome is likely responsible for the inhibition of interferon mediated by Nsp1-alpha. Participates also in the inhibition of host NF-kappa-B activation. Plays a role in the inhibition of the interferon-activated JAK/STAT signal transduction by mediating the ubiquitination and subsequent proteasomal degradation of host KPNA1. Plays a role in viral replication. Nsp2 and nsp2TF localize to different intracellular compartments. Produced by a -2 ribosomal frameshift.