Kyozuka J, Fujimoto H, Izawa T, Shimamoto K
Plantech Research Institute, Yokohama, Japan.
Mol Gen Genet. 1991 Aug;228(1-2):40-8. doi: 10.1007/BF00282445.
In order to analyze expression of the maize alcohol dehydrogenase 1 gene (Adh1), its promoter was fused with the gusA reporter gene and introduced into rice by protoplast transformation. Histochemical analysis of transgenic plants and their progeny showed that the maize Adh1 promoter is constitutively expressed in root caps, anthers, anther filaments, pollen, scutellum, endosperm and shoot and root meristem of the embryo. Induction of expression by the Adh1 promoter was examined using seedlings derived from selfed progeny of the transgenic plants. The results showed that expression of the Adh1 promoter was strongly induced (up to 81-fold) in roots of seedlings after 24 h of anaerobic treatment, concomitant with an increase in the level of gusA mRNA. 2,4-D also induced Adh1 promoter-directed expression of gusA to a similar extent. In contrast, little induction by anaerobic treatment was detected in transformed calli, leaves or roots of primary transformants or shoots of seedlings. A detailed examination of seedling roots during anaerobic treatment revealed that the induction started first at the meristem and after 3 h there was strong induction in the elongation zone which is located 1-2 mm above the meristem; the induction then progressed upward from this region. Our results suggest that transgenic rice plants carrying the gusA reporter gene fused with promoters are useful for the study of anaerobic regulation of genes derived from graminaceous species.
为了分析玉米乙醇脱氢酶1基因（Adh1）的表达情况，将其启动子与gusA报告基因融合，并通过原生质体转化法导入水稻。对转基因植株及其后代进行组织化学分析表明，玉米Adh1启动子在根冠、花药、花丝、花粉、盾片、胚乳以及胚的茎尖和根尖分生组织中组成型表达。利用转基因植株自交后代的幼苗检测Adh1启动子的诱导表达情况。结果显示，厌氧处理24小时后，幼苗根中Adh1启动子的表达被强烈诱导（高达81倍），同时gusA mRNA水平增加。2,4-D也能在相似程度上诱导gusA的Adh1启动子指导的表达。相比之下，在转化愈伤组织、初级转化体的叶片或根以及幼苗的茎中，厌氧处理几乎检测不到诱导作用。对厌氧处理期间的幼苗根进行详细检查发现，诱导首先在分生组织开始，3小时后在位于分生组织上方1-2毫米处的伸长区有强烈诱导；然后诱导从该区域向上发展。我们的结果表明，携带与启动子融合的gusA报告基因的转基因水稻植株可用于研究禾本科物种基因的厌氧调控。
