EMSA and DNase I Protection Assays of the NBS Consensus A, Radiolabeled DNA containing the NBS consensus (sequence shown in panel E) was incubated alone (no protein) or with 10 pmol and 30 pmol of recombinant hNUDR. Samples were separated on a 4% nondenaturing polyacrylamide gel and analyzed by autoradiography. B–D, Radiolabeled double-stranded DNA containing one copy of the NBS consensus (B, bottom strand labeled and C, top strand labeled) or two copies of the NBS consensus (D, top strand labeled) was left untreated (U), or was treated with DNase I in the absence (O) or presence of increasing amounts of recombinant hNUDR (indicated by the wedge). Samples were separated on 6% denaturing sequencing gels and analyzed by autoradiography. The protected regions in panels A–C are indicated by hatched bars to the right of each panel, and the nucleotide sequences protected are shown by the corresponding hatched bars above or below the sequences shown in panels E and F. The NBS consensus sequences are shown in bold capital letters.