Figure 8.

 Partial duplex DNAs but not double-stranded DNAs are bound by p95. Assays contained single-stranded competitor DNA (Random-18) as well as double-stranded poly[d(I–C)]. The percentage of probe bound was quantitated and indicated below the appropriate lane as %. (A) Reactions were performed in sets of three, with the first lane showing probe alone (20 nm); the second with added p95 at 50 nm; and the third with added p95 at 150 nm. The fully telomeric sequence used in lanes 1–3 is d(G₄T₂)₃. Other substrates contain G-rich, telomeric overhangs of 5 nucleotides (lanes 4–6); 11 nucleotides (lanes 7–9); 17 nucleotides (lanes 10–12); or 29 nucleotides (lanes 13–15) at the 3′ end or at the 5′ end of 11 nucleotides (lanes 16–18); or 17 nucleotides (lanes 19–21). Oligonucleotides were also annealed to generate fully double-stranded DNAs with 17 nucleotides of 3′ telomeric sequence (lanes 22–24); 11 nucleotides of 5′ telomeric sequence (lanes 25–27); or fully nontelomeric sequence (lanes 28–30). Open bars indicate nontelomeric sequence; solid bars indicate telomeric sequence. (B) The G-rich strands of the 3′ overhang substrates in A were radiolabeled and compared to their partial duplex counterparts. Reactions are in sets of two, with the first lane showing the probe alone (20 nm), and the second with added p95 at 100 nm.