4AT9:
reference: NF45 dimerizes with NF90, Zfr and SPNR via a conserved domain that has a nucleotidyltransferase fold., Wolkowicz UM, Cook AG, Nucleic Acids Res. 2012 Oct 1;40(18):9356-68. doi: 10.1093/nar/gks696. Epub 2012 , Jul 24. PMID: 22833610

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