2MJJ:
reference: A tetrahelical DNA fold adopted by tandem repeats of alternating GGG and GCG tracts., Kocman V, Plavec J, Nat Commun. 2014 Dec 15;5:5831. doi: 10.1038/ncomms6831. PMID: 25500730

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