Clugston C K, Barnett L K, Urwin N A, Jenkins G I
Department of Biochemistry, University of Glasgow, Scotland, UK.
Photochem Photobiol. 1990 Jul;52(1):23-8. doi: 10.1111/j.1751-1097.1990.tb01750.x.
We have investigated the photoreceptors controlling transcription of genes encoding the small subunit (rbcS) of ribulose 1,5-bisphosphate carboxylase-oxygenase in green leaf tissue of pea (Pisum sativum). RbcS transcription was measured by hybridising labelled transcripts of isolated nuclei to rbcS cDNA clones. Transfer of green Pisum leaf tissue to darkness for 5 h causes a substantial decrease in the rate of rbcS transcription and the rate is restored rapidly when the plants are returned to white light. Low fluence rates of red light are ineffective in restoring the rate of rbcS transcription, suggesting that phytochrome alone does not fully mediate the response. Blue light is similarly effective to white light of an equal fluence rate (120 mumol m-2 s-1) in restoring the rate of rbcS transcription in the dark-treated plants, indicating that a blue light photoreceptor is involved. However, red light at the same fluence rate produces about 65% of the effect of blue or white light, showing that the blue light photoreceptor is not the only photoreceptor controlling rbcS transcription in the green leaf tissue. The identity of the photoreceptor responsible for the red light effect is discussed. Similar effects of blue and red light are observed at the level of transcript abundance in dark-grown pea leaf tissue given a brief illumination with red light, which potentiates the tissue for rapid transcript accumulation in white light.
我们研究了控制豌豆（Pisum sativum）绿叶组织中编码1,5 - 二磷酸核酮糖羧化酶 - 加氧酶小亚基（rbcS）的基因转录的光感受器。通过将分离细胞核的标记转录本与rbcS cDNA克隆杂交来测量rbcS转录。将绿色豌豆叶组织转移到黑暗中5小时会导致rbcS转录速率大幅下降，当植物重新置于白光下时，转录速率会迅速恢复。低通量的红光无法恢复rbcS转录速率，这表明仅光敏色素不能完全介导该反应。在恢复黑暗处理植物中的rbcS转录速率方面，蓝光与相同通量率（120 μmol m-2 s-1）的白光效果相似，这表明涉及一种蓝光光感受器。然而，相同通量率的红光产生的效果约为蓝光或白光的65%，这表明蓝光光感受器不是控制绿叶组织中rbcS转录的唯一光感受器。本文讨论了负责红光效应的光感受器的身份。在用红光短暂照射的黑暗生长豌豆叶组织的转录本丰度水平上，观察到了蓝光和红光的类似效应，这使得该组织能够在白光下快速积累转录本。
