POLLEN SPECIFICITY ELEMENTS RESIDE IN 30 BP OF THE PROXIMAL PROMOTERS OF 2 POLLEN-EXPRESSED GENES
POLLEN SPECIFICITY ELEMENTS RESIDE IN 30 BP OF THE PROXIMAL PROMOTERS OF 2 POLLEN-EXPRESSED GENES
复制标题
DOI：
10.1105/tpc.7.3.373
复制
发表时间：
1995-03-01
期刊：
影响因子：
11.6
通讯作者：
MCCORMICK, S
中科院分区：
文献类型：
--
作者：
EYAL, Y;CURIE, C;MCCORMICK, S
功能分析先前确定了维持晚花药番茄LAT52和LAT59基因在番茄花粉中高水平表达所需的最小启动子区域。在这里，我们现在定义了直接花粉特异性的元素。我们使用了一个由两种细胞类型组成的瞬时检测系统，这两种细胞类型分别表达LAT基因和“功能丧失”和“功能获得”方法。在瞬时实验和转基因植物中分析的连接子替代突变体鉴定出了LAT52和LAT59的近端启动子区域，该区域对于它们在花粉中的表达至关重要，并且当与异种花菜花叶病毒35S核心启动子融合时，该区域具有花粉特异性。体内竞争实验表明，一个共同的反式作用因子与两个LAT基因启动子的花粉特异性区相互作用，表明一个共同的机制调节它们的坐标表达。邻近的上游元件LAT52的52/56盒和LAT59的56/59盒参与了花粉表达水平的调节。52/56盒子可能是GT-1转录因子家族成员结合的靶标。
Functional analyses previously identified minimal promoter regions required for maintaining high-level expression of the late anther tomato LAT52 and LAT59 genes in tomato pollen. Here, we now define elements that direct pollen specificity. We used a transient assay system consisting of two cell types that differentially express the LAT genes and both ''loss-of-function'' and ''gain-of-function'' approaches. Linker substitution mutants analyzed in the transient assay and in transgenic plants identified 30-bp proximal promoter regions of LAT52 and LAT59 that are essential for their expression in pollen and that confer pollen specificity when fused to the heterologous cauliflower mosaic virus 35S core promoter. In vivo competition experiments demonstrated that a common trans-acting factor interacts with the pollen specificity region of both LAT gene promoters and suggested that a common mechanism regulates their coordinate expression. Adjacent upstream elements, the 52/56 box in LAT52 and the 56/59 box in LAT59, are involved in modulating the level of expression in pollen. The 52/56 box may be a target for the binding of a member of the GT-1 transcription factor family.