FIG. 4.

The ssDNA-dependent inhibition of the E1-RPA interaction varies with oligonucleotide length. Either purified BPV1 E1 (A) or SV40 Tag (B) was immobilized in ELISA wells. The wells were blocked and incubated with RPA that had been preincubated with increasing concentrations of a 10-, 16-, 31-, or 75-nt oligonucleotide consisting of alternating thymines and guanines. The wells were washed, and the retained RPA was detected with a monoclonal antibody to RPA32. The bars depict the standard deviation calculated from at least four separate experiments (symbols without bars indicate that standard deviations were less than the size of the symbol).