Gibberellins (GAs) are endogenous hormones that play a predominant role in regulating plant stature by increasing cell division and elongation in stem internodes. The product of the GA 2-oxidase gene from Phaseolus coccineus (PcGA2ox1) inactivates C(19)-GAs, including the bioactive GAs GA(1 )and GA(4), by 2beta-hydroxylation, reducing the availability of these GAs in plants. The PcGA2ox1 gene was introduced into Solanum melanocerasum and S. nigrum (Solanaceae) by Agrobacterium-mediated transformation with the aim of decreasing the amounts of bioactive GA in these plants and thereby reducing their stature. The transgenic plants exhibited a range of dwarf phenotypes associated with a severe reduction in the concentrations of the biologically active GA(1) and GA(4). Flowering and fruit development were unaffected. The transgenic plants contained greater concentrations of chlorophyll b (by 88%) and total chlorophyll (11%), although chlorophyll a and carotenoid contents were reduced by 8 and 50%, respectively. This approach may provide an alternative to the application of chemical growth retardants for reducing the stature of plants, particularly ornamentals, in view of concerns over the potential environmental and health hazards of such compounds.

中文翻译：

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来自菜豆的赤霉素 2-氧化酶基因的过度表达增强赤霉素失活并诱导茄属物种的侏儒症。

赤霉素 (GA) 是内源性激素，通过增加茎节间的细胞分裂和伸长，在调节植物身高方面发挥主要作用。来自菜豆 (PcGA2ox1) 的 GA 2-氧化酶基因产物通过 2β-羟基化使 C(19)-GAs，包括生物活性 GAs GA(1) 和 GA(4) 失活，降低了这些 GAs 在植物中的可用性. PcGA2ox1 基因通过农杆菌介导的转化被引入到茄属植物和 S. nigrum（茄科）中，目的是减少这些植物中生物活性 GA 的数量，从而降低它们的身高。转基因植物表现出一系列与生物活性 GA(1) 和 GA(4) 浓度严重降低相关的矮化表型。开花和果实发育不受影响。转基因植物含有更高浓度的叶绿素 b（88%）和总叶绿素（11%），尽管叶绿素 a 和类胡萝卜素的含量分别减少了 8% 和 50%。鉴于对此类化合物的潜在环境和健康危害的担忧，该方法可为应用化学生长抑制剂降低植物，特别是观赏植物的身材提供替代方案。