FIGURE 10.

Location of Pol III-specific subunits on a surface view of elongating Pol III. The image is based on the cryoelectron microscopy structure of elongating Pol III (Protein Data Bank code 5FJ8) (56), and the DNA was extended based on the complete transcription bubble reported previously (75). The DNA template and non-template strands are colored in light blue and dark blue, respectively. The arrow points to downstream DNA, and the RNA molecule in the active site cleft is colored magenta. The highlighted Pol III subunits are Rpc31 (green), Rpc34 (purple), Rpc37 (red), Rpc53 (orange), and Rpc82 (tan). Note that the N-terminal 270 amino acids of Rpc53 are flexible and are not depicted due to the lack of structural data.