Structural Modeling Identifies a Conserved ADAR1 dsRBDIII Motif Predicted to Interact with PKR at Thr451

A conserved W768/F769/P770 (WFP) motif in ADAR1 dsRBD III is predicted to form a PKR interaction interface, but its disruption does not significantly reduce PKR association.

• Why it matters: ADAR1 and PKR association is established, yet the molecular determinants governing their interaction remain unclear.
• What they did: Molecular docking highlighted the WFP motif as a potential interface; coimmunoprecipitation tested single substitutions and WFP deletion, and RNase treatment assessed RNA dependence.
• The result: RNase reduced PKR coimmunoprecipitation by ~tenfold without abolishing interaction, suggesting ADAR1–PKR association is predominantly RNA dependent, with the WFP motif mainly stabilizing binding.