2 CLASSES OF CIS SEQUENCES CONTRIBUTE TO TISSUE-SPECIFIC EXPRESSION OF A PAL2 PROMOTER IN TRANSGENIC TOBACCO
2 CLASSES OF CIS SEQUENCES CONTRIBUTE TO TISSUE-SPECIFIC EXPRESSION OF A PAL2 PROMOTER IN TRANSGENIC TOBACCO
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DOI：
10.1046/j.1365-313x.1995.07060859.x
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发表时间：
1995-06-01
期刊：
影响因子：
7.2
通讯作者：
BEVAN, M
中科院分区：
文献类型：
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作者：
HATTON, D;SABLOWSKI, R;BEVAN, M
编码苯丙氨酸解氨酶(PAL)的基因在植物发育过程中以复杂的模式表达，并对光、病原菌入侵、机械损伤和其他胁迫做出响应。对转基因烟草中菜豆PAL2基因启动子的分析表明，一些负责发育表达的区域是功能补偿的。包含发育表达模式所需的所有顺式序列的最小序列在转录起始点的-254bp以内。对该区域的足迹和电泳迁移率改变分析研究揭示了潜在的顺式序列，这些顺式序列与由小片段缺失和启动子融合定义的功能结构域相吻合。在最小-254bp启动子的背景下，这些潜在顺式序列的突变改变了组织特异性表达模式，证实了这些序列对体内表达的重要性。提出了一个启动子的功能模型，该模型预测三个AC元件可能是Myb蛋白结合部位，与G盒相互作用，指导观察到的组织特异性表达的复杂模式。
Genes encoding phenylalanine ammonia-lyase (PAL) are expressed in a complex pattern during plant development and in response to light, pathogen ingress, mechanical damage and other stresses. Analysis of the promoter of the bean PAL2 gene in transgenic tobacco has shown that some regions responsible for developmental expression are functionally compensatory. The minimum sequence containing all cis sequences necessary for developmental patterns of expression is within -254 bp of the transcription start site. Footprinting and electrophoretic mobility shift assay studies of this region revealed potential cis sequences which coincided with the functional domains defined by small deletions and promoter fusions. Mutations in these potential cis sequences in the context of the minimal -254 bp promoter altered tissue-specific expression patterns, confirming the importance of these sequences for expression in vivo. A functional model for the promoter is presented which predicts that three AC-elements, which are possible Myb protein binding sites, together with a G-box, interact to direct the complex patterns of tissue-specific expression observed.