Fig 3.

The N-terminal portion of ZfL2-1 ORF1p exchanges strands between double- and single-stranded DNAs. Strand exchange assays were performed in the presence of Trx or the Trx fusion of the N-terminal portion of ZfL2-1 ORF1p (Trx-N-ORF1p). Schematic diagrams of the strand exchange assays and the resulting autoradiograms are shown. In the diagrams, oligonucleotides are indicated by blue and red lines. Their sequences are shown in Table 2. One strand of each initial duplex was labeled by ³²P at its 5′ end (asterisks). (A, B) Left, schematic diagram of the strand exchange proceeding in the direction increasing the stability of the duplex (A) or causing no stability change (B). Mismatches in the duplex are shown by notches in the line. Right, a representative autoradiogram of the strand exchange with the proteins of interest. (C) Top, schematic diagrams of the strand exchange proceeding in the direction decreasing (left) or increasing (right) the stability of the duplex. Bottom, representative autoradiograms of the strand exchanges. The strand exchanges were conducted for 30 min with increasing amounts of Trx or Trx-N-ORF1p (triangles; 0.063, 0.25, and 1 μM each protein). The left lane of each autoradiogram shows the result with no protein (0).