Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK.
Cell. 2009 Dec 11;139(6):1170-9. doi: 10.1016/j.cell.2009.11.029.
Photoperiod sensors allow physiological adaptation to the changing seasons. The prevalent hypothesis is that day length perception is mediated through coupling of an endogenous rhythm with an external light signal. Sufficient molecular data are available to test this quantitatively in plants, though not yet in mammals. In Arabidopsis, the clock-regulated genes CONSTANS (CO) and FLAVIN, KELCH, F-BOX (FKF1) and their light-sensitive proteins are thought to form an external coincidence sensor. Here, we model the integration of light and timing information by CO, its target gene FLOWERING LOCUS T (FT), and the circadian clock. Among other predictions, our models show that FKF1 activates FT. We demonstrate experimentally that this effect is independent of the known activation of CO by FKF1, thus we locate a major, novel controller of photoperiodism. External coincidence is part of a complex photoperiod sensor: modeling makes this complexity explicit and may thus contribute to crop improvement.
光周期传感器允许生理适应季节变化。流行的假说认为，通过将内源性节律与外部光信号耦合来感知日照长度。虽然在哺乳动物中尚未进行，但已有足够的分子数据可用于对植物进行定量测试。在拟南芥中，时钟调节基因 CONSTANS（CO）和 FLAVIN、KELCH、F-BOX（FKF1）及其光敏蛋白被认为构成了外部巧合传感器。在这里，我们通过 CO、其靶基因 FLOWERING LOCUS T（FT）和生物钟来模拟光和计时信息的整合。在其他预测中，我们的模型表明 FKF1 激活了 FT。我们通过实验证明，这种效果独立于已知的 FKF1 对 CO 的激活，因此我们找到了光周期的一个主要的、新的控制器。外部巧合是复杂光周期传感器的一部分：建模使这种复杂性变得明显，因此可能有助于作物改良。
