Crystal structure of RIG-I C-terminal domain bound to blunt-ended double-strand RNA without 5' triphosphate. Academic Article uri icon


  • RIG-I recognizes molecular patterns in viral RNA to regulate the induction of type I interferons. The C-terminal domain (CTD) of RIG-I exhibits high affinity for 5' triphosphate (ppp) dsRNA as well as blunt-ended dsRNA. Structures of RIG-I CTD bound to 5'-ppp dsRNA showed that RIG-I recognizes the termini of dsRNA and interacts with the ppp through electrostatic interactions. However, the structural basis for the recognition of non-phosphorylated dsRNA by RIG-I is not fully understood. Here, we show that RIG-I CTD binds blunt-ended dsRNA in a different orientation compared to 5' ppp dsRNA and interacts with both strands of the dsRNA. Overlapping sets of residues are involved in the recognition of blunt-ended dsRNA and 5' ppp dsRNA. Mutations at the RNA-binding surface affect RNA binding and signaling by RIG-I. These results provide the mechanistic basis for how RIG-I recognizes different RNA ligands.

published proceedings

  • Nucleic Acids Res

altmetric score

  • 3

author list (cited authors)

  • Lu, C., Ranjith-Kumar, C. T., Hao, L., Kao, C. C., & Li, P.

citation count

  • 54

complete list of authors

  • Lu, Cheng||Ranjith-Kumar, CT||Hao, Lujiang||Kao, C Cheng||Li, Pingwei

publication date

  • March 2011