FIGURE 4.

The Rad51 nucleoprotein complex is the most effective inhibitor of Rad52-mediated DNA annealing. The experiments were carried out as described under “Experimental Procedures” except that in A Rad51 was preassembled on heterologous dsDNA (400 nm) at 37 °C for 5 min before addition to the RPA-ssDNA complexes. DNA was 100 bp in length. B, experiments were carried out as in A except that Rad51 was preassembled on heterologous ssDNA (400 nm). DNA was 100-nucleotides in length. In both panels, Rad52 only (blue squares) and with Rad51 (blue triangles), heterologous DNA (green squares), and Rad51-DNA complex (green triangles) with ATP are shown. The experiments carried out in the presence of ATPγS in lieu of ATP are represented by the open symbols: +Rad51, orange triangles; +heterologous DNA, red squares; and +Rad51 and DNA (both), red triangles. The results are the averages obtained from at least two independent experiments, and the error bars represent the variation (where absent, the error bars are smaller than the symbol).