Figure 3.

Competition assays with different oligonucleotides. The 27h probe (10 nM) was incubated with 42.5 ng/µl of HNE in 50 mM HEPES buffer pH 7.2, containing 0.1 M KCl, 1 mM MgCl₂, 5% sucrose, 0.5 µg/µl dT26 and 0.5 µg/µl ds26 for 15 min on ice and run at 4°C on an 8% polyacrylamide gel (see Materials and Methods). For each competitor, concentrations of 10 nM, 100 nM, 1 µM and 10 µM (from left to right) were used. The sequences of the competitors are reported in Table 1. It should be noted that oligonucleotides that compete poorly, such as 17h and 21ct, are not recognised by other nuclear HeLa proteins (not shown).