Figure 3.

Deoxynucleotidyl transferase activity of the recombinant AtREV1 protein. The primer P13 was ³²P-labeled at the 5′ end and annealed with each of the templates, preparing four template/primer pairs: 30G (B and F), 30A (C and G), 30T (D and H), and 30C (E and I). The nucleotide sequences around the primer terminus are shown in A. The underlined bases represent the variation of templates. 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–E) or 1 mm manganese chloride (F–I) at 30°C for 10 min. The reaction products were resolved in 20% polyacrylamide gels containing 8 m urea and visualized by autoradiography.