Figure 3.

Effect of IrrE on binding of DdrO to RDRM‐containing promoter regions. (a) DdrO (0.8 μmol/L) was incubated with DNA fragments containing the promoter of dnaK, ddrA or ddrD, or the intergenic region of the divergent ddr O_C and Deide_20580 genes that are both radiation‐induced (DNA fragments at 51, 64, 57 and 57 nmol/L, respectively). The sample in lane 5 also contained 1 μg of Poly(dI‐dC). (b) Electrophoretic mobility shift assays (EMSA) with DNA fragments containing ddr O_C‐Deide_20580 intergenic region or ddrA promoter region in presence of IrrE. When both IrrE (or IrrE‐E83Q) and DdrO were present (1.7 μmol/L each), either IrrE and DdrO were pre‐incubated at 37°C (lane 5) or room temperature (lanes 6, 8, 14 and 16) prior to addition of DNA (symbols + and ‐ in grey background), or DdrO and DNA were incubated prior to addition of and incubation with IrrE (lanes 7, 9, 15 and 17; white symbols in black background)