Biological Institute II, University of Freiburg, D 78 Freiburg, Germany.
Plant Physiol. 1975 Nov;56(5):660-4. doi: 10.1104/pp.56.5.660.
Light stimulates the accumulation of cytoplasmic and plastid rRNA in the cotyledons of mustard (Sinapis alba L.) seedlings. This effect is mediated by phytochrome. Continuous far red irradiation and brief red light pulses (the effect of which is reversible by brief far red light pulses) increase the amount of 1.3 x 10(6) + 0.7 x 10(6) and 1.1 x 10(6) + 0.56 x 10(6) molecular weight rRNA species. Large and small ribosomal subunit RNAs are maintained in a 1:1 molar ratio in both cytoplasm and plastids, irrespective of seedling age and light treatment. Continuous white fluorescent light (which saturates chlorophyll synthesis) is less effective than continuous far red light (essentially no chlorophyll synthesis) in producing the response, indicating that the accumulation of plastid rRNA is independent of the build-up of a functional photosynthetic apparatus. We conclude that the transcription of cytoplasmic and plastid rRNA cistrons is under phytochrome control.
光照刺激芥菜（Sinapis alba L.）幼苗子叶中细胞质和质体 rRNA 的积累。这种效应是由光敏色素介导的。连续远红光照射和短暂红光脉冲（其效应可被短暂远红光脉冲逆转）增加了 1.3 x 10(6) + 0.7 x 10(6) 和 1.1 x 10(6) + 0.56 x 10(6) 分子量 rRNA 种类的数量。无论幼苗年龄和光照处理如何，细胞质和质体中的大、小核糖体亚基 RNA 均保持 1:1 的摩尔比。连续的白色荧光光（饱和叶绿素合成）在产生反应方面不如连续远红光（基本上没有叶绿素合成）有效，这表明质体 rRNA 的积累与功能光合器官的建立无关。我们得出结论，细胞质和质体 rRNA 顺式作用元件的转录受光敏色素控制。
