Nagao R T, Goekjian V H, Hong J C, Key J L
Department of Botany, University of Georgia, Athens 30602.
Plant Mol Biol. 1993 Mar;21(6):1147-62. doi: 10.1007/BF00023610.
The promoter region of a soybean auxin-responsive gene, GmAux28, was analyzed to identify protein-binding DNA sequences that may be involved in regulation of expression. Using DNase I footprinting and gel mobility shift assays, multiple regions of interaction, including eight major protein-binding sites, were observed in the GmAux28 gene. Two sequence motifs, TGACGACA and TCCACGTGTC, related to as-1/Hex and G-box elements, respectively, found in several plant promoters, were identified. Four distinct A/T-rich domains were identified; such A/T-rich domains appear to modulate, but not to specify, the expression of many genes. Two new sequence motifs, delta-1 (D1) and delta-4 (D4) were also identified. D1 and D4 share a very similar core sequence, TAGTxxCTGT and TAGTxCTGT, respectively. In gel mobility shift analyses, D1 and D4 elements exhibit a complex interaction of binding proteins. The GmAux22 promoter also contains D1-related elements which compete with the GmAux28 elements. Sequence comparisons have identified D1/D4-like sequences in several other auxin-responsive genes suggesting the possible importance of D1/D4 and the respective binding proteins in the regulation of expression of these genes.
对大豆生长素应答基因GmAux28的启动子区域进行了分析，以鉴定可能参与表达调控的蛋白质结合DNA序列。通过DNA酶I足迹法和凝胶迁移率变动分析，在GmAux28基因中观察到多个相互作用区域，包括八个主要的蛋白质结合位点。鉴定出了两个分别与几种植物启动子中发现的as-1/Hex和G-box元件相关的序列基序TGACGACA和TCCACGTGTC。鉴定出了四个不同的富含A/T的结构域；这种富含A/T的结构域似乎对许多基因的表达起调节作用，但不是特异性作用。还鉴定出了两个新的序列基序，δ-1（D1）和δ-4（D4）。D1和D4分别具有非常相似的核心序列TAGTxxCTGT和TAGTxCTGT。在凝胶迁移率变动分析中，D1和D4元件表现出结合蛋白的复杂相互作用。GmAux22启动子也含有与D1相关的元件，这些元件与GmAux28元件竞争。序列比较在其他几个生长素应答基因中鉴定出了D1/D4样序列，表明D1/D4和各自的结合蛋白在这些基因表达调控中可能具有重要作用。
