Figure 5.

Fidelity of hPolη in the presence of magnesium or manganese. (A) To examine the fidelity of DNA synthesis, reactions were run with 3 nM hPolη, 20 nM DNA/DNA, 100 μM individual dNTP, and 4 mM Mg²⁺ or Mn²⁺, as indicated, for 1 min. The first templating nucleotide is shown above each panel and the correct incoming nucleotides are framed below the pictures. (B) RNA synthesis reactions were performed as in (A) except using 20 nM RNA/DNA and 2000 μM rNTP for 15 min. (C) Time course reactions were performed with 1 nM hPolη, 20 nM RNA/DNA, 4000 μM of individual rNTPs, and 4 mM Mn for the indicated times.