Fig. 1. Cryo-EM structure of the Pol III ITC.

a Nucleic acid scaffold used. The non-template (top) and template (bottom) strands are depicted in cyan. Mismatched sequence is shown as separate strands. RNA is shown in red. TATA box is depicted in yellow. TFIIIB binding region and transcription bubble position are also labeled. b Cryo-EM reconstruction of the Pol III ITC. Pol III is colored gray, and the nucleic acid template is colored cyan. The TFIIIB subunits are depicted in blue (Brf1), red (TBP), and orange (Bdp1). Two views, front (left) and bottom (right), are shown. c Two views of the Pol III ITC model. Components are colored the same as in b