The leftward promoter of bacteriophage lambda. Structure, biological activity, and influence by adjacent regions.

摘要: The effect of regions adjacent to the lambda PL promoter was studied using a sequence deleted in an A/T-rich segment immediately upstream from promoter. High resolution thermal denaturation analysis showed that undeleted sequence, as isolated on 360-bp restriction fragment (360-PL) melted two distinct steps. Since (230-PL) melts at higher temperature than any portion 360-PL, is more stable denaturation. This increased stability also suggested by transcription assay which strong binding RNA polymerase inhibited low temperature. required become functional did 360-PL fragment. Furthermore, bound 230-PL displaced heparin faster rate and initiates reduced rate. Thus, several criteria less active parent sequence. Evidence presented arguing deletion does not alter directly recognized polymerase. Therefore, altered reducing activity changing some other level overall structure. These results suggest outside regulatory protein can affect genetic expression site.