'Green revolution' genes encode mutant gibberellin response modulators
'Green revolution' genes encode mutant gibberellin response modulators
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DOI：
10.1038/22307
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发表时间：
1999-07-15
期刊：
影响因子：
64.8
通讯作者：
Harberd, NP
中科院分区：
文献类型：
--
作者：
Peng, JR;Richards, DE;Harberd, NP
世界小麦产量在20世纪60年代和70年代大幅增加，因为农民迅速采用了所谓的“绿色革命”的新品种和耕作方法（1-4）。新品种更矮，以秸秆生物量为代价增加粮食产量，并且更耐风雨（3，4）。这些小麦是矮的，因为它们对植物生长激素赤霉素的反应异常。这种对赤霉素的反应降低是由两个降低高度-1（Rht-B1和Rht-D1）基因座之一的突变矮化等位基因赋予的（4，5）。在这里，我们表明Rht-B1/Rht-D1和玉米矮化-8（d8）（6，7）是拟南芥赤霉素不敏感（GAI）基因的直向同源物（8，9）。这些基因编码类似核转录因子的蛋白质，并含有SH 2样（10）结构域，表明磷酸酪氨酸可能参与赤霉素信号传导。六种不同的直向同源矮化突变体等位基因编码的蛋白质在保守的氨基末端赤霉素信号传导结构域中发生改变。含有突变体GAI等位基因的转基因水稻植物对赤霉素的反应降低并且矮化，这表明突变体GAI直向同源物可用于在广泛的作物物种中增加产量。
World wheat grain yields increased substantially in the 1960s and 1970s because farmers rapidly adopted the new varieties and cultivation methods of the so-called 'green revolution(1-4). The new varieties are shorter, increase grain yield at the expense of straw biomass, and are more resistant to damage by wind and rain(3,4). These wheats are short because they respond abnormally to the plant growth hormone gibberellin, This reduced response to gibberellin is conferred by mutant dwarfing alleles at one of two Reduced height-1 (Rht-B1 and Rht-D1) loci(4,5), Here we show that Rht-B1/Rht-D1 and maize dwarf-8 (d8)(6,7) are orthologues of the Arabidopsis Gibberellin Insensitive (GAI) gene(8,9). These genes encode proteins that resemble nuclear transcription factors and contain an SH2-like(10) domain, indicating that phosphotyrosine may participate in gibberellin signalling. Six different orthologous dwarfing mutant alleles encode proteins that are altered in a conserved amino-terminal gibberellin signalling domain, Transgenic rice plants containing a mutant GAI allele give reduced responses to gibberellin and are dwarfed, indicating that mutant GAI orthologues could be used to increase yield in a wide range of crop species.