LZF1, a HY5-regulated transcriptional factor, functions in Arabidopsis de-etiolation
LZF1, a HY5-regulated transcriptional factor, functions in Arabidopsis de-etiolation
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DOI：
10.1111/j.1365-313x.2008.03401.x
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发表时间：
2008-04-01
期刊：
影响因子：
7.2
通讯作者：
Wu, Shu-Hsing
中科院分区：
文献类型：
--
作者：
Chang, Chiung-Swey Joanne;Li, Yi-Hang;Wu, Shu-Hsing
我们研究了野生型和HY5缺陷型突变体拟南芥在早期光形态建成过程中的差异基因表达模式，HY5是基因表达对光刺激响应的一个重要正调控因子，目的是鉴定其表达依赖于HY5的光响应基因。这些基因表达数据鉴定出光调节锌指蛋白1（LZF1），它是一个编码此前未被鉴定的C2C2 - CO B - box转录调控因子的基因。HY5对LZF1具有正向反式激活活性，并且在体内对LZF1启动子具有结合亲和力。HY5是诱导LZF1表达所必需的，但并不充分。在远红光下，lzf1中的花青素含量显著降低，远红光对诱导LZF1是最有效的光。在过表达LZF1的植株中，PAP1/MYB75的表达升高，这导致转基因拟南芥中花青素的过度积累。在lzf1突变体中，从黄化质体到叶绿体的转变以及叶绿素的积累明显受损。我们提供了分子证据表明LZF1通过调节编码叶绿体蛋白的基因影响叶绿体的生物发生和功能。在没有HY5的情况下，LZF1的突变导致对光调节的下胚轴伸长抑制以及花青素和叶绿素积累的光敏感性进一步降低。我们的数据表明LZF1是在拟南芥去黄化过程中起作用的一个正调控因子。
We surveyed differential gene expression patterns during early photomorphogenesis in both wild-type and mutant Arabidopsis defective in HY5, an influential positive regulator of the responses of gene expression to a light stimulus, to identify light-responsive genes whose expression was HY5 dependent. These gene-expression data identified light-regulated zinc finger protein 1 (LZF1), a gene encoding a previously uncharacterized C2C2-CO B-box transcriptional regulator. HY5 has positive trans-activating activity toward LZF1 and binding affinity to LZF1 promoter in vivo. HY5 is needed but not sufficient for the induction of LZF1 expression. Anthocyanin content is significantly diminished in lzf1 under far red, which is the most efficient light for the induction of LZF1. The expression of PAP1/MYB75 is elevated in plants overexpressing LZF1, which leads to the hyperaccumulation of anthocyanin in transgenic Arabidopsis. The transition from etioplast to chloroplast and the accumulation of chlorophyll were notably compromised in the lzf1 mutant. We provide molecular evidence that LZF1 influences chloroplast biogenesis and function via regulating genes encoding chloroplast proteins. In the absence of HY5, mutation of LZF1 leads to further reduced light sensitivity for light-regulated inhibition of hypocotyl elongation and anthocyanin and chlorophyll accumulation. Our data indicate that LZF1 is a positive regulator functioning in Arabidopsis de-etiolation.