Loop of fate: structural and mechanistic insights into hnRNPA1 binding to the hepatitis C virus RNA

Superimposition of the 20 lowest-energy structures of the RNA element showing the apical loop region in two views rotated by 180°. The loop residues (U9277–C9288) are highlighted in red, while the remaining stem residues are shown in gray. The labeled nucleotides indicate residues within the loop region. The conformational ensemble illustrates the structural variability and orientation of the loop nucleotides relative to the stable helical stem.