6EOJ:
reference: Architecture of eukaryotic mRNA 3'-end processing machinery., Casanal A, Kumar A, Hill CH, Easter AD, Emsley P, Degliesposti G, Gordiyenko Y, Santhanam B, Wolf J, Wiederhold K, Dornan GL, Skehel M, Robinson CV, Passmore LA, Science. 2017 Oct 26. pii: eaao6535. doi: 10.1126/science.aao6535. PMID: 29074584

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