6DCC:
reference: Structural basis of 7SK RNA 5'-gamma-phosphate methylation and retention by MePCE., Yang Y, Eichhorn CD, Wang Y, Cascio D, Feigon J, Nat Chem Biol. 2018 Dec 17. pii: 10.1038/s41589-018-0188-z. doi:, 10.1038/s41589-018-0188-z. PMID: 30559425

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