4FQG:
reference: Specific Interaction of the Transcription Elongation Regulator TCERG1 with RNA Polymerase II Requires Simultaneous Phosphorylation at Ser2, Ser5, and Ser7 within the Carboxyl-terminal Domain Repeat., Liu J, Fan S, Lee CJ, Greenleaf AL, Zhou P, J Biol Chem. 2013 Apr 12;288(15):10890-901. doi: 10.1074/jbc.M113.460238. Epub, 2013 Feb 22. PMID: 23436654

This OCA Structure page
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