Abstract (Expand)
Clock-regulated pathways coordinate the response of many developmental processes to changes in photoperiod and temperature. We model two of the best-understood clock output pathways in Arabidopsis, … which control key regulators of flowering and elongation growth. In flowering, the model predicted regulatory links from the clock to cycling DOF factor 1 (CDF1) and flavin-binding, KELCH repeat, F-box 1 (FKF1) transcription. Physical interaction data support these links, which create threefold feed-forward motifs from two clock components to the floral regulator FT. In hypocotyl growth, the model described clock-regulated transcription of phytochrome-interacting factor 4 and 5 (PIF4, PIF5), interacting with post-translational regulation of PIF proteins by phytochrome B (phyB) and other light-activated pathways. The model predicted bimodal and end-of-day PIF activity profiles that are observed across hundreds of PIF-regulated target genes. In the response to temperature, warmth-enhanced PIF4 activity explained the observed hypocotyl growth dynamics but additional, temperature-dependent regulators were implicated in the flowering response. Integrating these two pathways with the clock model highlights the molecular mechanisms that coordinate plant development across changing conditions.
Authors: D. D. Seaton, R. W. Smith, Y. H. Song, D. R. MacGregor, K. Stewart, G. Steel, J. Foreman, S. Penfield, T. Imaizumi, A. J. Millar, K. J. Halliday
Date Published: 21st Jan 2015
Publication Type: Not specified
PubMed ID: 25600997
Citation: Mol Syst Biol. 2015 Jan 19;11(1):776. doi: 10.15252/msb.20145766.