Fig. 4
From: Mechanism of transcription-coupled DNA modification recognition
The structure of RNA pol II elongation complex with 5caC, in which 5caC adopts the similar “above-bridge-helix” conformation. 5caC can form a specific hydrogen bond with key residue Q531 of the Rpb2 subunit. The bridge helix is shown in green, and RNA and DNA are shown in red and blue, respectively