Bowler C, Neuhaus G, Yamagata H, Chua N H
Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-6399.
Cell. 1994 Apr 8;77(1):73-81. doi: 10.1016/0092-8674(94)90236-4.
We have previously used single-cell assays in a phytochrome-deficient tomato mutant to demonstrate that phytochrome signaling involves heterotrimeric G proteins, calcium, and calmodulin. While G protein activation could stimulate full chloroplast development and anthocyanin pigment biosynthesis, calcium and calmodulin could not induce anthocyanins and were only able to stimulate the development of immature chloroplasts lacking cytochrome b6f and photosystem I core components. We now report that cyclic GMP is able to trigger the production of anthocyanins, and that a combination of cyclic GMP with calcium can induce the development of fully mature chloroplasts containing all the photosynthetic machinery. Furthermore, using reporter genes for these different pathways (cab-gus, chs-gus, and fnr-gus) we demonstrate that cGMP and calcium act primarily by modulating gene expression.
我们之前在一个缺乏光敏色素的番茄突变体中使用单细胞分析，以证明光敏色素信号传导涉及异源三聚体G蛋白、钙和钙调蛋白。虽然G蛋白激活可以刺激叶绿体的完全发育和花青素色素的生物合成，但钙和钙调蛋白不能诱导花青素的产生，只能刺激缺乏细胞色素b6f和光系统I核心成分的未成熟叶绿体的发育。我们现在报告，环鸟苷酸能够触发花青素的产生，并且环鸟苷酸与钙的组合可以诱导含有所有光合机制的完全成熟叶绿体的发育。此外，使用针对这些不同途径的报告基因（cab-gus、chs-gus和fnr-gus），我们证明cGMP和钙主要通过调节基因表达起作用。
