Klevecz Robert R, Bolen James, Forrest Gerald, Murray Douglas B
Dynamics Group, Department of Biology, Beckman Research Institute of the City of Hope Medical Center, Duarte, CA 91010, USA.
Proc Natl Acad Sci U S A. 2004 Feb 3;101(5):1200-5. doi: 10.1073/pnas.0306490101. Epub 2004 Jan 20.
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 approximately 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.
来自酵母连续同步培养系统的微阵列分析显示转录在全基因组范围内振荡。在这个约40分钟的呼吸和还原循环中，转录水平的最大值出现在三个几乎等距的间隔处。在循环的还原阶段，两个时间簇（5329个中的4679个）表达量最大，而第三个簇（650个）在呼吸阶段表达量最大。转录在功能上被组织成氧化还原状态超簇，已知在呼吸或还原中起重要作用的基因在循环的相反阶段合成。转录循环以40分钟的间隔在一定比例的群体中控制DNA复制的同步爆发。将DNA合成限制在循环的还原阶段可能是一种在进化上重要的机制，可减少复制过程中对DNA的氧化损伤。
