小麦矮秆突变体DC20赤霉素合成及信号转导途径关键基因表达分析

Expression of Genes for Gibberellins Synthesis and Signal Transduction in Dwarf Mutant DC20 of Wheat( Triticum aestivum L. )

小麦矮秆突变体DC20是经高能混合粒子场处理得到的,表现为赤霉素敏感型。本文采用实时荧光定量PCR技术,研究该突变体矮秆性状与GA合成及信号转导途径相关基因表达的关系。共检测编码GA合成途径关键酶和编码信号转导途径作用因子的10个关键基因。其中,编码内-贝壳烯杉氧化酶(KO)的GA3基因和编码正调控因子基因GAMYB的表达量极显著下调,下调倍数分别为20.0、3.1;2个编码负调控因子基因GAI和SPY显著上调,上调倍数分别为2.3、1.3。外源GA3(赤霉酸)处理能够抑制编码负调控因子基因GAI、SPY和RGA的转录,而GA合成关键酶基因GA3及正调控因子基因GAMYB转录水平显著升高表明DC20矮秆基因对GA相关途径的受外源GA3的调节。

Dwarfing wheat mutant DC20 was gibberellin acid （GA3） sensitive, which was induced by mixed particle field. In this paper, expression of genes related with gibberellins biosynthesis and signal transduction were analyzed. Among the target 10 genes, GA3 encoding of gibberellins synthetic enzyme Ent-kaurene oxidase （KO）was down- regulated 20.0 times in the mutant than that in the wild type, and GAMYB encoding positive acting factor down-regulated 3.1 times, genes GAI and SPY encoding reverse acting factors were up-regulated 2. 3 and 1. 3 times respectively. Exogenous GA3 inhibited the transcription of GAI, SPY and RGA, while the transcriptions of GA3 and GAMYB were significantly increased after GA3 treatment. It was concluded that the effect of DC20 dwarfing gene relative to GA pathways were regulated by exogenous GA3.