A genomewide oscillation in transcription gates DNA replication and cell cycle
- Dynamics Group, Department of Biology, Beckman Research Institute of the City of Hope Medical Center, Duarte, CA 91010
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Edited by Steven L. McKnight, University of Texas Southwestern Medical Center, Dallas, TX, and approved November 26, 2003 (received for review October 7, 2003)
Abstract
Microarray analysis from a yeast continuous synchrony culture system shows a genomewide oscillation in transcription. Maximums in transcript levels occur at three nearly equally spaced intervals in this ≈40-min cycle of respiration and reduction. Two temporal clusters (4,679 of 5,329) are maximally expressed during the reductive phase of the cycle, whereas a third cluster (650) is maximally expressed during the respiratory phase. Transcription is organized functionally into redox-state superclusters with genes known to be important in respiration or reduction being synthesized in opposite phases of the cycle. The transcriptional cycle gates synchronous bursts in DNA replication in a constant fraction of the population at 40-min intervals. Restriction of DNA synthesis to the reductive phase of the cycle may be an evolutionarily important mechanism for reducing oxidative damage to DNA during replication.
