Cis-analysis of a seed protein gene promoter: the conservative RY repeat CATGCATG within the legumin box is essential for tissue-specific expression of a legumin gene.
Cis-analysis of a seed protein gene promoter: the conservative RY repeat CATGCATG within the legumin box is essential for tissue-specific expression of a legumin gene.
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DOI：
10.1046/j.1365-313x.1992.t01-45-00999.x
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发表时间：
1992-03
期刊：
影响因子：
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通讯作者：
H. Bäumlein;Istvan Nagy;Raimundo Villarroel;Dirk Inzé;U. Wobus
中科院分区：
文献类型：
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作者：
H. Bäumlein;Istvan Nagy;Raimundo Villarroel;Dirk Inzé;U. Wobus
一个含有蚕豆LeB4基因5′-侧翼区和5′-非编码序列的2.4 kb片段在转基因烟草中介导了高水平的种子特异性表达。该豆科蛋白上游序列的缺失衍生物被融合到npt-II报告基因中，以确定嵌合构建物在稳定转化的烟草植株中的组织特异性活性。结果表明，在上游序列566 bp内存在正调控的增强子样顺式元件。然而，最重要的是，这些元件只有在与豆蔻蛋白盒-95位附近的核心基序CATGCATG结合时才能完全发挥作用，因为在一个完整的2.4 kb上游序列中，该基序被6 bp的缺失破坏后，会大大降低种子中的表达。同时，在叶片中观察到低水平表达。在其他几个植物基因前面出现了类似的CATGCATG一致的嘌呤和嘧啶碱基对交替的顺式元件，这表明该基序在更广泛的植物启动子中发挥了功能作用。
A 2.4 kb fragment containing the 5'-flanking region and the 5'-noncoding sequence of the Vicia faba legumin gene LeB4 mediates high level seed-specific expression in transgenic tobacco plants. Deleted derivatives of this legumin upstream sequence were fused to the npt-II reporter gene to determine the tissue-specific activity of the chimeric constructs in stably transformed tobacco plants. The results indicate the presence of positive regulatory, enhancer-like cis elements within 566 bp of the upstream sequence. Most importantly, however, these elements are only fully functional in conjunction with the core motif CATGCATG of the legumin box around position -95, since destruction of the motif by a 6 bp deletion in an otherwise intact 2.4 kb upstream sequence drastically reduces expression in seeds. At the same time, low level expression in leaves is observed. The occurrence of similar CATGCATG consensus cis elements with alternating purine and pyrimidine base pairs in front of several other plant genes suggests a functional role of the motif in a wider range of plant promoters.