Editors' ChoiceMOLECULAR BIOLOGY

Fast and Slow

Science Signaling  29 Jan 2008:
Vol. 1, Issue 4, pp. ec40
DOI: 10.1126/stke.14ec40

During gene transcription, some activator proteins bind cyclically to their promoters, with periodicities of ~30 seconds (fast cycling) or ~30 minutes (slow cycling). Karpova et al. now show that these different cycles are distinct but that the same transcription activator can engage in both cycling activities on the same promoter at the same time. It seems that the fast cycle is involved in transcription initiation, whereas the slow cycle modulates the number of promoters accessible for initiation.

T. S. Karpova, M. J. Kim, C. Spriet, K. Nalley, T. J. Stasevich, Z. Kherrouche, L. Heliot, J. G. McNally, Concurrent fast and slow cycling of a transcriptional activator at an endogenous promoter. Science 319, 466-469 (2008). [Abstract] [Full Text]