Phototropin from Chlamydomonas reinhardtii is functional in Arabidopsis thaliana
Phototropin from Chlamydomonas reinhardtii is functional in Arabidopsis thaliana
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DOI：
10.1093/pcp/pci037
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发表时间：
2005-02-01
影响因子：
4.9
通讯作者：
Nagatani, A
中科院分区：
文献类型：
--
作者：
Onodera, A;Kong, SG;Nagatani, A
趋光素是一种植物蓝光光感受器，介导重要的蓝光反应，例如高等植物的向光性、叶绿体定位和气孔开放。在拟南芥中，已知有两种趋光素，即趋光素 I 和 2。最近，在单细胞绿藻莱茵衣藻中，鉴定出了一种向光素同系物。它表现出与高等植物向光素相似的光化学特性，并参与衣藻有性生命周期的多个步骤。在这里，我们在拟南芥中表达了衣藻向光素，以检查它是否在远缘植物物种中具有活性。用含有与花椰菜花叶病毒 35S 启动子融合的衣藻向光素 cDNA 的载体转化缺乏向光素 I 和 2 的拟南芥突变体。根据 RNA 凝胶印迹和免疫印迹分析，将所得细胞系分为高表达、中表达和低表达。在高表达系中恢复了典型的向光素反应。这些结果证明衣藻向光素在高等植物中具有功能。因此，尽管其明显的生理功能多种多样，但促光素作用的基本机制是高度保守的。
Phototropin, a plant blue light photoreceptor, mediates important blue light responses such as phototropism, chloroplast positioning and stomatal opening in higher plants. In Arabidopsis thaliana, two phototoropins, phototropin I and 2, are known. Recently, in the unicellular green alga, Chlamydomonas reinhardtii, a phototropin homolog was identified. It exhibits photochemical properties similar to those of higher plant phototropins and is involved in multiple steps of the sexual life cycle of Chlamydomonas. Here, we expressed Chlamydomonas phototropin in Arabidopsis to examine whether it is active in a distantly related plant species. The Arabidopsis mutant deficient in both phototropin I and 2 was transformed with a vector containing Chlamydomonas phototropin cDNA fused to a cauliflower mosaic virus 35S promoter. The resulting lines were classified into high, medium and low expressers based on RNA gel blot and immunoblot analyses. Typical phototropin responses were restored in high expression lines. These results demonstrate that Chlamydomonas phototropin is functional in higher plants. Hence, the basic mechanism of phototropin action is highly conserved, even though its apparent physiological functions are quite diverse.