A novel class of plant-specific zinc-dependent DNA-binding protein that binds to A/T-rich DNA sequences
A novel class of plant-specific zinc-dependent DNA-binding protein that binds to A/T-rich DNA sequences
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DOI：
10.1093/nar/29.20.4097
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发表时间：
2001-10-15
影响因子：
14.9
通讯作者：
Sasaki, Y
中科院分区：
文献类型：
--
作者：
Nagano, Y;Furuhashi, H;Sasaki, Y
互补DNA编码。从豌豆中分离出一种DNA结合蛋白，命名为PLATZ 1（植物富含AT序列和锌结合蛋白1）。该蛋白质的氨基酸序列与从高等植物基因组序列预测的其他未表征蛋白质的氨基酸序列相似。然而，在植物界之外还没有发现旁系同源序列。在这些旁系同源蛋白中的多重比对表明，几个半胱氨酸和组氨酸残基是不变的，这表明这些蛋白是一类新的锌依赖性DNA结合蛋白，具有两个相距较远的区域，C-x（2）-H-x（11）-C-x（2-）C-x（（4-5））-C-x（2）-C-x（（3-7））-H-x（2）-H和C-x（2）-C-x（（10-11））-C-x（3）-C。在电泳迁移率变动分析中，锌螯合剂1，10-邻菲咯啉抑制DNA结合，DNA结合需要两个遥远的锌结合区域。用（65）ZnCl（2）进行的蛋白质印迹表明，这两个区域都是锌结合活性所必需的。PLATZ 1蛋白非特异性地结合到富含A/T的序列，包括豌豆GTpra 2和质体蓝素petE基因的上游区域。PLATZ 1的表达抑制了那些含有荧光素酶基因编码序列的报告构建体的表达，所述荧光素酶基因编码序列由花椰菜花叶病毒（CaMV）35 S90启动子驱动，所述启动子与富含A/T的序列的串联重复融合。这些结果表明PLATZ 1是一类新的植物特异性锌依赖性DNA结合蛋白，负责富含A/T序列介导的转录抑制。
Complementary DNA encoding. a DNA-binding protein, designated PLATZ1 (plant AT-rich sequence-and zinc-binding protein 1), was isolated from peas. The amino acid sequence of the protein is similar to those of other uncharacterized proteins predicted from the genome sequences of higher plants. However, no paralogous sequences have been found outside the plant kingdom. Multiple alignments among these paralogous proteins show that several cysteine and histidine residues are invariant, suggesting that these proteins are a novel class of zinc-dependent DNA-binding proteins with two distantly located regions, C-x(2)-H-x(11)-C-x(2-)C-x((4-5))-C- x(2)-C-x((3-7))-H-x(2)-H and C-x(2)-C-x((10-11))-C-x(3)-C. In an electrophoretic mobility shift assay, the zinc chelator 1,10-o-phenanthroline inhibited DNA binding, and two distant zinc-binding regions were required for DNA binding. A protein blot with (65)ZnCl(2) showed that both regions are required for zinc-binding activity. The PLATZ1 protein non-specifically binds to A/T-rich sequences, including the upstream region of the pea GTPase pra2 and plastocyanin petE genes. Expression of the PLATZ1 repressed those of the reporter constructs containing the coding sequence of luciferase gene driven by the cauliflower mosaic virus (CaMV) 35S90 promoter fused to the tandem repeat of the A/T-rich sequences. These results indicate that PLATZ1 is a novel class of plant-specific zinc-dependent DNA-binding protein responsible for A/T-rich sequence-mediated transcriptional repression.