Two novel AP2/ERF domain proteins interact with cis-element VWRE for wound-induced expression of the Tobacco tpoxN1 gene.
Two novel AP2/ERF domain proteins interact with cis-element VWRE for wound-induced expression of the Tobacco tpoxN1 gene.
复制标题
DOI：
10.1111/j.1365-313x.2007.03111.x
复制
发表时间：
2007-04
期刊：
影响因子：
--
通讯作者：
K. Sasaki;I. Mitsuhara;S. Seo;Hiroyuki Ito;H. Matsui;Y. Ohashi
中科院分区：
文献类型：
--
作者：
K. Sasaki;I. Mitsuhara;S. Seo;Hiroyuki Ito;H. Matsui;Y. Ohashi
维管系统特异性和伤口响应顺式元件（VWRE）已被确定为一种新的顺式元件的烟草过氧化物酶基因，tpoxN 1的伤口诱导和维管系统特异性表达。在这里，我们分离出两个独立的克隆编码VWRE结合蛋白的酵母单杂交筛选。由于基因产物具有AP 2/ERF（APETALA 2/ethylene-responsive factor）结构域，并且转录物在创伤后瞬时积累，我们将其命名为创伤响应性AP 2/ERF样因子1（WRAF 1）和WRAF 2。两个WRAF的AP 2/ERF结构域具有97%的同源性，并且被分类为ERF亚家族B-4。凝胶迁移率变化分析表明，WRAFs特异性结合VWRE，其中不包含已知的其他AP 2/ERF蛋白的顺式元件。WRAFs的结合活性被发现定位于AP 2/ERF结构域。WRAFs反式激活一个含有VWRE的四个串联重复序列的启动子，但不激活突变的VWRE。WRAF基因的过表达导致潜在靶基因tpoxN 1在未受伤的转基因植物中组成型表达。这些结果表明，新的转录因子WRAF 1和WRAF 2作为tpoxN 1基因表达的正调节因子结合VWRE。
The vascular system-specific and wound-responsive cis-element (VWRE) has been identified as a novel cis-element for wound-induced and vascular system-specific expression of the tobacco peroxidase gene, tpoxN1. Here we isolated two independent clones that encode VWRE binding proteins by yeast one-hybrid screening. As the gene products have an AP2/ERF (APETALA2/ethylene-responsive factor) domain, and the transcripts were accumulated transiently after wounding, we named them wound-responsive AP2/ERF-like factor 1 (WRAF1) and WRAF2. The AP2/ERF domains of the two WRAFs share 97% homology, and are classified into the ERF subfamily B-4. Gel mobility shift analysis indicated that WRAFs specifically bind VWRE, which contains no known cis-elements for other AP2/ERF proteins. The binding activity of the WRAFs was found to be localized in the AP2/ERF domain. The WRAFs transactivated a promoter containing four tandem repeats of the VWRE, but not that of the mutated VWRE. Overexpression of the WRAF genes led to constitutive expression of the potential target gene, tpoxN1, in unwounded transgenic plants. These results indicate that the novel transcription factors WRAF1 and WRAF2 bind the VWRE as positive regulators for the expression of the tpoxN1 gene.