“…RNAP II with hyperphosphorylated CTD Ser2 pauses at 1–5 kbp downstream of pA sites of active genes in human cells. The CPA factors CstF and CPSF preferentially bind to the Ser2 hyperphosphorylated CTD; thus, the “pause site” is the gene region where CPA and transcriptional termination processes are initiated and executed (Anamika, Gyenis, & Tora, ; Eaton & West, ; Glover‐Cutter, Kim, Espinosa, & Bentley, ; Gromak, West, & Proudfoot, ; Hsin & Manley, ; Lian et al, ; Richard & Manley, ; Swinburne, Meyer, Liu, Silver, & Brodsky, ; West, Gromak, & Proudfoot, ). An endonuclease, CPSF73, cleaves the pre‐mRNA at 10–30 nucleotides downstream of the pA signal (Eaton et al, ; Mandel et al, ).…”