Figure 3.

Binding of HeLa cell nuclear proteins to the HPV-16 NRE. Nuclear proteins were UV-crosslinked to radiolabeled RNA probes spanning the NRE and 20 nt of downstream region (probe N), the adjacent 153-nt region (probe L), or the HSV-1 UL44 gene poly(A) site (probe U). A 1–50 molar excess of unlabeled probe was used for competition as indicated. (A) Competition of unlabeled riboprobe N against labeled probe N or labeled probe L. (B) Competition of unlabeled riboprobe L against labeled probe L or labeled probe N.