Figure 3.

Effect of Pronase on activity of fraction B. Gel retardation assays were performed in the presence or absence of SeqA (0.03 ng/μl) and/or fraction B (FxB, 10 ng/μl), as indicated. Pronase-treated fraction B (FxB* and FxB**) was prepared by incubating a mixture of fraction B (0.11 μg/μl) and Pronase in 10 mM Pipes (pH 6.5) for 30 min at room temperature followed by heating at 100°C for 6 min. In reaction c (FxB*), the concentration of Pronase was 0.009 μg/μl; in reactions d, i, and j (FxB**), Pronase concentration was 0.09 μg/μl. In reaction j, untreated fraction B was added to the reaction mixture after the addition of FxB**. Lanes a–d and e–j represent experiments done on separate days with different exposure times during autoradiography.