5VJI:
reference: Crystal Structure of the CLOCK Transactivation Domain Exon19 in Complex with a Repressor., Hou Z, Su L, Pei J, Grishin NV, Zhang H, Structure. 2017 Aug 1;25(8):1187-1194.e3. doi: 10.1016/j.str.2017.05.023. Epub, 2017 Jun 29. PMID: 28669630

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