K160 in the RNA‐binding domain of the orf virus virulence factor OV20.0 is critical for its functions in counteracting host antiviral defense

The OV20.0 virulence factor of orf virus antagonizes host antiviral responses. One mechanism through which it functions is by inhibiting activation the dsRNA-activated protein kinase R (PKR) sequestering dsRNA and physically interacting with PKR. Sequence alignment indicated that several key residues critical for binding were conserved in OV20.0, their contribution to OV20.O function was investigated this study. We found F141, K160, R164 responsible dsRNA-binding ability OV20.0. Interestingly, mutation at K160 (K160A) diminished OV20.0–PKR interaction further reduced inhibitory effect on PKR activation. Nevertheless, homodimerization not influenced K160A. domain suppression RNA interference demonstrated plants. In summary, essential particularly its ultimately contributes