1SRO:
reference: The solution structure of the S1 RNA binding domain: a member of an ancient nucleic acid-binding fold., Bycroft M, Hubbard TJ, Proctor M, Freund SM, Murzin AG, Cell 1997 Jan 24;88(2):235-42. PMID: 9008164

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