1T2S:
reference: Nucleic acid 3'-end recognition by the Argonaute2 PAZ domain., Lingel A, Simon B, Izaurralde E, Sattler M, Nat Struct Mol Biol 2004 Jun;11(6):576-7. Epub 2004 May 23. PMID: 15156196

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).