PT - JOURNAL ARTICLE AU - Harmer, Stacey L. AU - Hogenesch, John B. AU - Straume, Marty AU - Chang, Hur-Song AU - Han, Bin AU - Zhu, Tong AU - Wang, Xun AU - Kreps, Joel A. AU - Kay, Steve A. TI - Orchestrated Transcription of Key Pathways in <em>Arabidopsis</em> by the Circadian Clock AID - 10.1126/science.290.5499.2110 DP - 2000 Dec 15 TA - Science PG - 2110--2113 VI - 290 IP - 5499 4099 - http://science.sciencemag.org/content/290/5499/2110.short 4100 - http://science.sciencemag.org/content/290/5499/2110.full SO - Science2000 Dec 15; 290 AB - Like most organisms, plants have endogenous biological clocks that coordinate internal events with the external environment. We used high-density oligonucleotide microarrays to examine gene expression in Arabidopsis and found that 6% of the more than 8000 genes on the array exhibited circadian changes in steady-state messenger RNA levels. Clusters of circadian-regulated genes were found in pathways involved in plant responses to light and other key metabolic pathways. Computational analysis of cycling genes allowed the identification of a highly conserved promoter motif that we found to be required for circadian control of gene expression. Our study presents a comprehensive view of the temporal compartmentalization of physiological pathways by the circadian clock in a eukaryote.