4DA4:
reference: Structure-based mechanistic insights into DNMT1-mediated maintenance DNA methylation., Song J, Teplova M, Ishibe-Murakami S, Patel DJ, Science. 2012 Feb 10;335(6069):709-12. PMID: 22323818

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