Figure 4.
Deoxynucleotidyl transferase activity of the recombinant AtREV1 protein opposite the AP site. The primer P13 was 32P-labeled at the 5′ end and annealed with the template 30G or 30AP. The nucleotide sequences are shown in A. The underlined bases represent the variation of templates; O indicates the AP site in template 30AP. One hundred and sixty nanograms of AtREV1 recombinant protein and the indicated template/primer were incubated with 0.1 mm of a single dNTP (G, A, T, or C), 0.1 mm each of all four dNTPs (N), or no dNTP (−) under standard reaction conditions with 2 mm magnesium chloride (B and D) or 1 mm manganese chloride (C and D) at 30°C for 10 min. The reaction products were resolved in 20% polyacrylamide gels containing 8 m urea, and then visualized by autoradiography.