Plays a role in the inhibition of host immune response. Participates in the inhibition of host autophagy by interacting with and inhibiting host PKR/EIF2AK2. This interaction also prevents the interferon-induced shut down of protein synthesis following viral infection. Downmodulates the host RLR signaling pathway via direct interaction with host DDX58 and IFIH1. Associates with endogenous HSP90 to disrupt the HSP90-TBK1 complex and induces destabilization of host TBK1 through a proteasome-dependent pathway. May also participate in nuclear egress of viral particles through interactions with host NCL and regulation of the viral UL34 mRNA. Associates with RNA derived from the 60S ribosomal subunits. Seems to form large heterogeneous polymers of up to 200 identical subunits in the cytoplasm. Interacts with host EIF2AK2. Interacts with host NCL. Interacts with host DDX58; this interaction prevents DDX58 binding to host MAVS. Interacts with host IFIH1; this interaction prevents host IFH1 binding to MAVS. Interacts with host HSP90; this interaction inhibits TBK1-induced interferon induction. Following infection, it is released into the cell cytoplasm. The N-terminal tetrapeptide may be responsible for virion incorporation. The C-terminal half, rich in Arg and Pro residues, seems to be responsible for the RNA-binding activity, and for the association with ribosomes and the localization to the nucleolus. This region may adopt a poly-L-proline II helix secondary structure. May be phosphorylated on Ser residues by host kinases. Belongs to the simplex virus US11 protein family.