Chen Meng, Chory Joanne, Fankhauser Christian
Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA.
Annu Rev Genet. 2004;38:87-117. doi: 10.1146/annurev.genet.38.072902.092259.
Plants utilize several families of photoreceptors to fine-tune growth and development over a large range of environmental conditions. The UV-A/blue light sensing phototropins mediate several light responses enabling optimization of photosynthetic yields. The initial event occurring upon photon capture is a conformational change of the photoreceptor that activates its protein kinase activity. The UV-A/blue light sensing cryptochromes and the red/far-red sensing phytochromes coordinately control seedling establishment, entrainment of the circadian clock, and the transition from vegetative to reproductive growth. In addition, the phytochromes control seed germination and shade-avoidance responses. The molecular mechanisms involved include light-regulated subcellular localization of the photoreceptors, a large reorganization of the transcriptional program, and light-regulated proteolytic degradation of several photoreceptors and signaling components.
植物利用几类光感受器在大范围的环境条件下微调生长和发育。感受UV-A/蓝光的向光素介导多种光反应，从而优化光合产量。光子捕获后发生的初始事件是光感受器的构象变化，激活其蛋白激酶活性。感受UV-A/蓝光的隐花色素和感受红光/远红光的光敏色素协同控制幼苗建立、生物钟的校准以及从营养生长到生殖生长的转变。此外，光敏色素控制种子萌发和避荫反应。涉及的分子机制包括光感受器的光调节亚细胞定位、转录程序的大规模重组以及几种光感受器和信号成分的光调节蛋白水解降解。
