Piechulla B
University of Rostock, Department of Molecular Physiology of Plants and Microorganisms, Rostock, Germany.
Chronobiol Int. 1999 Mar;16(2):115-28. doi: 10.3109/07420529909019080.
Photosynthesis is one of the important processes that enable life on earth. To optimize photosynthesis reactions during a solar day, most of them are timed to be active during the light phase. This includes the components of the thylakoid membranes in chloroplasts. Prominent representatives are the proteins of the light-harvesting complex (LHC). The synthesis of both the Lhc mRNA and the LHC protein occurs during the day and is regulated by the circadian clock, exhibiting the following pattern: increasing levels after sunrise, reaching a maximum around noon, and decreasing levels in the afternoon. To elucidate the involved control elements and regulatory circuits, the following strategies were applied: (1) analysis of promoters of Lhc genes, (2) analysis of DNA binding proteins, and (3) screening and investigation of mutants. The most promising elements found so far that may be involved in mediating the circadian rhythmicity of Lhc mRNA oscillations are a myb-like transcription factor CCA1 (Wang et al. 1997) and the corresponding DNA binding sequence (Piechulla et al. 1998).
光合作用是使地球上的生命得以存在的重要过程之一。为了在一个太阳日内优化光合作用反应，其中大部分反应被安排在光照阶段活跃。这包括叶绿体中类囊体膜的成分。突出的代表是光捕获复合体（LHC）的蛋白质。Lhc mRNA和LHC蛋白质的合成均在白天进行，并受生物钟调节，呈现出以下模式：日出后水平升高，中午左右达到最大值，下午水平下降。为了阐明其中涉及的控制元件和调节回路，采用了以下策略：（1）分析Lhc基因的启动子，（2）分析DNA结合蛋白，（3）筛选和研究突变体。迄今为止发现的最有希望参与介导Lhc mRNA振荡的昼夜节律的元件是一种类myb转录因子CCA1（Wang等人，1997年）和相应的DNA结合序列（Piechulla等人，1998年）。
