Visualizing the determinants of viral RNA recognition by innate immune sensor RIG-I.
Publication Type:Journal Article
Source:Structure, Volume 20, Issue 11, p.1983-8 (2012)
Keywords:DEAD Box Protein 58, DEAD-box RNA Helicases, Humans, Immunity, Innate, Models, Molecular, RNA, Viral
<p>Retinoic acid inducible gene-I (RIG-I) is a key intracellular immune receptor for pathogenic RNAs, particularly from RNA viruses. Here, we report the crystal structure of human RIG-I bound to a 5' triphosphorylated RNA hairpin and ADP nucleotide at 2.8 Å resolution. The RNA ligand contains all structural features that are essential for optimal recognition by RIG-I, as it mimics the panhandle-like signatures within the genome of negative-stranded RNA viruses. RIG-I adopts an intermediate, semiclosed conformation in this product state of ATP hydrolysis. The structure of this complex allows us to visualize the first steps in RIG-I recognition and activation upon viral infection.</p>