Lam E, Chua N H
Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021.
J Biol Chem. 1989 Dec 5;264(34):20175-6.
The genes coding for the light-harvesting chlorophyll a/b-binding protein of photosystem II (cab) in wheat are regulated by phytochrome and an endogenous circadian clock. The regulation by these factors has been shown to be at the transcriptional level. Here we show that the phase of cab gene expression is reset by light to dark transition of the previous day. The time of light to dark transition is linearly related to the time of maximal cab gene expression under free running conditions in darkness. We propose that in nature the onset of darkness resets the phase of the circadian clock, which regulates the timing of cab gene expression, so as to anticipate the time of sunrise in the following day.
小麦中编码光系统II捕光叶绿素a/b结合蛋白（cab）的基因受光敏色素和内源性生物钟调控。这些因子的调控作用已被证明发生在转录水平。在此我们表明，cab基因表达的相位可通过前一天的光暗转换被重置。光暗转换时间与黑暗中自由运转条件下cab基因最大表达时间呈线性相关。我们提出，在自然环境中，黑暗的开始重置了生物钟的相位，生物钟调控cab基因表达的时间，从而预测次日日出的时间。
