Figure 2.

Competition experiments. Aliquots of the 330 mm NaCl phosphocellulose fraction were incubated with the labeled ds-oligonucleotide P3 in the presence of unlabeled P3 (lane 2) and the heterologous competitors PtrnF (20 bp, lanes 4 and 5) and Pnad5 (22 bp, lanes 6 and 7). The molar excesses in which the competing DNA molecules were added over P3 are indicated in the second line at the top. Binding reactions in the absence of mitochondrial proteins (lane 1) and in the absence of competitor (lane 2) served as negative and positive controls, respectively. A homologous competition experiment was performed to determine the molar excess of unlabeled P3 required for an almost complete suppression of the C1 and C2 signals (lane 3). Arrows at left indicate the positions of the DNA-protein complexes C1 and C2 and of the unbound ds-oligonucleotide P3.