Molecular dissection of the promoter of the light-induced and circadian-controlled APRR9 gene encoding a clock-associated component of Arabidopsis thaliana
Molecular dissection of the promoter of the light-induced and circadian-controlled APRR9 gene encoding a clock-associated component of Arabidopsis thaliana
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DOI：
10.1271/bbb.69.382
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发表时间：
2005-02-01
影响因子：
1.6
通讯作者：
Mizuno, T
中科院分区：
文献类型：
--
作者：
Ito, S;Nakamichi, N;Mizuno, T
在模式高等植物拟南芥中，一些与生物钟相关的蛋白质组分最近被鉴定。其中，拟南芥假反应调节子的一个小家族（APRR 1/TOC 1、APRR 3、APRR 5、APRR 7和APRR 9）是有趣的，因为最可能的时钟组件CAB表达I的时间（TOC 1）属于该家族。已经积累了一些证据来支持这样的观点，即不仅APRR 1/TOC 1，而且其他APRR家族成员对于更好地理解昼夜节律和光信号转导之间的分子联系至关重要。在APRR 1/TOC 1家族成员中，昼夜节律控制的APRR 9基因是独特的，因为其表达在转录水平上被光快速诱导。在这项研究中，我们解剖的光诱导和/或昼夜节律控制的APRR 9启动子的调控顺式元件，不仅采用携带T-DNA插入的APRR 9启动子的突变体植物，但也有一系列的APRR 9-启动子：：LUC（荧光素酶）报告，被引入到拟南芥培养细胞系（T87细胞）。将这些方法的结果结合在一起，我们提供了几条证据，证明APRR 9启动子包含至少两个独特的和可分离的调节顺式元件：负责光诱导表达的“L元件”，其次是APRR 9基本节律表达所必需的“R元件”。此外，APRR 1/TOC 1直接或间接参与了APRR 9的L元件介导的光反应。
In the model higher plant Arabidopsis thaliana, a number of circadian clock-associated protein components have recently been identified. Among them, a small family of ARABIDOPSIS PSEUDO-RESPONSE REGULATORS (APRR1/TOC1, APRR3, APRR5, APRR7, and APRR9) is interesting because the most probable clock component TIMING OF CAB EXPRESSION I (TOC1) belongs to this family. Several lines of evidence have already been accumulated to support the view that not only APRR1/TOC1 but also other APRR family members are crucial for a better understanding of the molecular link between circadian rhythm and light-signal transduction. Among the APRR1/TOC1 family members, the circadian-controlled APRR9 gene is unique in that its expression is rapidly induced by light at the level of transcription. In this study we dissected the regulatory cis-elements of the light-induced and/or circadian-controlled APRR9 promoter by employing not only a mutant plant carrying a T-DNA insertion in the APRR9 promoter, but also a series of APRR9-promoter::LUC (luciferase) reporters that were introduced into an Arabidopsis cultured cell line (T87 cells). Taking the results of these approaches together, we provide several lines of evidence that the APRR9 promoter contains at least two distinctive and separable regulatory cis-elements: an "L element" responsible for the light-induced expression, followed by an "R element" necessary for the fundamental rhythmic expression of APRR9. Furthermore, APRR1/ TOC1 was implicated in the L-element-mediated light response of APRR9, directly or indirectly.