Dedonder A, Rethy R, Fredericq H, Van Montagu M, Krebbers E
Laboratory of Plant Physiology, University of Gent, Belgium.
Plant Physiol. 1993 Mar;101(3):801-8. doi: 10.1104/pp.101.3.801.
Individual members of the Arabidopsis thaliana ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (rbcS) gene family are differentially regulated by light of different qualities. In 10-d-old etiolated seedlings, the expression of only three of the four genes is under inductive phytochrome control. rbcS mRNA levels reach a maximum (3- to 5-fold higher than the dark level) about 6 h after a red light pulse, but the rate of decay differs among the genes. Moreover, rbcS 2B requires a higher fluence for induction. At early stages of development, rbcS 1A, 2B, and 3B are highly expressed in the dark and cannot be further induced by red light, indicating a developmental component in the overall regulatory mechanism. Continuous light experiments indicate that high-irradiance responses may play a role in the induction of at least three of the four rbcS genes. Under conditions of phytochrome saturation, rbcS 1A is insensitive to blue light pulses, whereas among the three B locus genes, at least rbcS 3B appears to respond to a blue-light photoreceptor. These results add to the data suggesting that individual members of rbcS gene families in higher plants may be subject to a variety of differing regulatory mechanisms.
拟南芥1,5 - 二磷酸核酮糖羧化酶/加氧酶小亚基（rbcS）基因家族的各个成员受到不同性质光的差异调控。在10日龄的黄化幼苗中，四个基因中只有三个基因的表达受诱导性光敏色素控制。红光脉冲后约6小时，rbcS mRNA水平达到最大值（比黑暗水平高3至5倍），但各基因的衰减速率不同。此外，rbcS 2B诱导所需的光通量更高。在发育早期，rbcS 1A、2B和3B在黑暗中高度表达，不能被红光进一步诱导，这表明整体调控机制中存在发育成分。连续光照实验表明，高辐照度反应可能在四个rbcS基因中至少三个基因的诱导中起作用。在光敏色素饱和的条件下，rbcS 1A对蓝光脉冲不敏感，而在三个B位点基因中，至少rbcS 3B似乎对蓝光光受体有反应。这些结果进一步表明，高等植物中rbcS基因家族的各个成员可能受到多种不同的调控机制。
