Tan Ying, Merrow Martha, Roenneberg Till
Institute for Medical Psychology, University of Munich, Munich, Germany.
J Biol Rhythms. 2004 Apr;19(2):135-43. doi: 10.1177/0748730404263015.
Plants and animals use day or night length for seasonal control of reproduction and other biological functions. Overwhelming evidence suggests that this photoperiodic mechanism relies on a functional circadian system. Recent progress has defined how flowering time in plants is regulated by photoperiodic control of output pathways, but the underlying mechanisms of photoperiodism remain to be described. The authors investigate photoperiodism in a genetic model system for circadian rhythms research, Neurospora crassa. They find that both propagation and reproduction respond systematically to photoperiod. Furthermore, a nonreproductive light-regulated function is also enhanced under certain photoperiodic conditions. All of these photoperiodic responses require a functional circadian clock, in that they are absent in a clock mutant. Night break experiments show that measuring night length is one of the mechanisms used for photoperiod assessment. This represents the first formal report of photoperiodism in the fungi.
植物和动物利用白昼或黑夜的时长来季节性地控制繁殖及其他生物学功能。大量证据表明，这种光周期机制依赖于一个功能性的昼夜节律系统。最近的研究进展已经明确了植物开花时间是如何通过输出途径的光周期控制来调节的，但光周期现象的潜在机制仍有待阐述。作者们在用于昼夜节律研究的遗传模型系统——粗糙脉孢菌中研究光周期现象。他们发现，生长和繁殖都对光周期有系统性的反应。此外，在某些光周期条件下，一种非繁殖性的光调节功能也会增强。所有这些光周期反应都需要一个功能性的生物钟，因为在生物钟突变体中这些反应不存在。夜间中断实验表明，测量夜晚时长是用于光周期评估的机制之一。这是真菌中光周期现象的首份正式报告。
