Shah J, Klessig D F
Waksman Institute, Rutgers, State University of New Jersey, Piscataway 08855, USA.
Plant J. 1996 Dec;10(6):1089-101. doi: 10.1046/j.1365-313x.1996.10061089.x.
The tobacco pathogenesis-related PR-2d gene encodes an acidic beta-1,3-glucanase. Expression of the PR-2d: uidA(GUS) chimeric gene is induced in leaves undergoing the hypersensitive resistance response to tobacco mosaic virus and after treatment with salicylic acid (SA), a chemical believed to play an important role(s) in disease resistance. We have constructed transgenic tobacco plants which carry various segments of the PR-2d promoter fused to a heterologous core 35S promoter driving the uidA(GUS) reporter gene. Their analysis indicates that sequences from -364 to -288 upstream of the PR-2d transcription start site confer a high level of activation by SA (20-fold). Mutations within this sequence, located between -339 and -333, depressed SA activation. This region is also required for the SA-inducibility of a truncated PR-2d:GUS chimeric gene. Contained within this region is a 25 bp element located between -348 and -324 which was specifically recognized by nuclear factors from tobacco leaves. No conclusive differences were observed in the ability of proteins in nuclear extracts from water-treated versus SA-treated plants to bind to this cis element in vitro.
烟草病程相关蛋白PR-2d基因编码一种酸性β-1,3-葡聚糖酶。PR-2d:uidA（GUS）嵌合基因在对烟草花叶病毒产生过敏反应的叶片中以及在水杨酸（SA）处理后被诱导表达，水杨酸被认为在抗病性中起重要作用。我们构建了转基因烟草植株，这些植株携带PR-2d启动子的不同片段，与驱动uidA（GUS）报告基因的异源核心35S启动子融合。对它们的分析表明，PR-2d转录起始位点上游-364至-288的序列赋予了水杨酸高水平的激活作用（20倍）。位于-339至-333之间的该序列内的突变降低了水杨酸的激活作用。该区域对于截短的PR-2d:GUS嵌合基因的水杨酸诱导性也是必需的。该区域包含一个位于-348至-324之间的25bp元件，它被来自烟草叶片的核因子特异性识别。在水处理与水杨酸处理的植物的核提取物中的蛋白质体外结合该顺式元件的能力方面未观察到确凿的差异。
