FIG. 1.

EMSA analysis of CASTing-enriched probes. Oligonucleotide probes that formed DNA-protein complexes were amplified by PCR and radiolabeled by incorporation of [α-³²P]dCTP in the reaction mixture. These DNA probes were used in EMSAs with the GST-HPV₅₁E2 protein to form complexes. The original degenerate oligonucleotide pool (N₂₀S) was used as the template for the lane labeled round 0. The next five lanes represent amplified probes from rounds 6, 7, 8, and 9, as labeled above the EMSA. The final two lanes were loaded with complex formed between radiolabeled probe amplified by PCR from the pBPV1-E2BS plasmid, which contains the binding site sequence gagaACCGAATTCGGTagcc as the template with (+) or without (−) the GST-HPV₅₁E2 protein.