FIG. 8.

Alignment of sequences in motifs A and C conserved among polymerases. Motif A of other polymerases resembles motif I of Polη, except that Polη has an additional conserved acidic E residue at position 39 in the yeast protein. Motif C of other DNA polymerases resembles motif III of Polη in that they all contain two conserved acidic residues flanked by hydrophobic residues (h). In Pol I, the D residue in motif A is at position 705 and the D and E residues of motif C occur at positions 882 and 883, respectively. This figure is adapted from Fig. 1 of reference 18. R.T., reverse transcriptase.