FIG. 5.

Release of Pol I factors during transcription. PICs were formed for 45 min on either the WT or Δ−2 template using WT extract. After washing, PICs were resuspended in YTB with NTPs for 15 min. Factors that remain bound to the immobilized template were separated from released factors with a magnetic separator, resolved on an SDS-polyacrylamide gel, and identified by using Western blotting. Note that essentially all of Rrn3p releases from the WT template, a small fraction of Pol I (RPA34, RPA43), CF (RRN7, RRN11) and TBP release, and no UAF releases during transcription.