Extended Data Fig. 9: After RNA cleavage, FluPol is in a pre-initiation state and cap snatching is compatible with early Pol II elongation and pausing.
From: Mechanism of co-transcriptional cap snatching by influenza polymerase
a, Comparison of FluPol transcription pre-initiation state (PDB: 4WSB, yellow)48 with the pre-cleavage cap-snatching state (turquoise), post-cleavage cap-snatching state (pink), pre-initiation state (PDB: 6RR7, light purple)44 and elongation state (PDB: 7QTL, light blue)35. Only the priming loop, the 3′ vRNA, and the capped RNA are depicted. b, Comparison of post-cleavage and pre-initiation FluPol structure shows no significant protein rearrangement. Post-cleavage is shown in pink, and pre-initiation in transparent white (PDB:6RR7)44. b, The comparison of promoter-bound FluPol with the pre-cleavage FluPol structure shows the rotation of the cap-binding domain during substrate binding. Promoter-bound FluPol is shown in yellow, and pre-cleavage in turquoise (PDB:4WSB)44. d, Superposition of an early elongating FluPol onto the post-cleavage FluPol-Pol II-DSIF EC reveals no clash between the early elongating FluPol and the Pol II EC (PDB: 7QTL, light blue)35. e, Overlay of the pre-cleavage complex (this study) and the Pol II-CMTR1 EC (PDB:8P4F) shows that FluPol clashes with CMTR125. f, NELF binding to Pol II is compatible with the cap snatching as NELF and FluPol bind to different regions of Pol II (PDB: 6GML)49. g, FluPol clashes with SPT6 core in the activated elongation complex (PDB: 6GMH)50. h, Comparison of the post-cleavage structure with the Integrator complex bound to the paused Pol II EC (PDB: 8RBX)51 shows a clash between FluPol and the Integrator cleavage module. i, Comparison of the post-cleavage structure with yeast Rat1-Rai1 (homolog of human XRN2) bound to a yeast Pol II EC (PDB: 8JCH)75 shows a clash between FluPol and Rat1-Rai1.
