大豆GmNRT1.2a和GmNRT1.2b基因的克隆及功能探究

拟南芥中硝酸盐的吸收、转运和分配是通过硝酸盐转运蛋白(nitrate transporter, NRT)实现的。尽管之前的生物信息学分析推测大豆GmNRT1.2s可能参与共生固氮过程,但尚未开展相应的功能研究。本研究通过对其表达模式分析収现,GmNRT1.2a和GmNRT1.2b分别在根和叶中高表达,且受硝酸盐诱导,在接种根瘤菌与结瘤因子(nodfactors,NFs)后表达量明显升高。功能研究结果显示,过表达GmNRT1.2a或GmNRT1.2b后大豆根瘤数目显著增加。本研究为深入探究GmNRT1.2a和GmNRT1.2b调控大豆共生固氮过程的分子机制提供了一定的数据支持。

Cloning and functional analysis of GmNRT1.2a and GmNRT1.2b in soybean

Nitrate transporters (NRTs) have been found to be involved in nitrate uptake, transport and allocation in Arabidopsis. The role of GmNRT1.2s in soybean (Glycine max) symbiotic nitrogen fixation process has been speculated by bioinformatics analysis, however, its biological function has not been explored yet. In this study, we mainly focused on analyzing the expression pattern and biological function of GmNRT1.2a and GmNRT1.2b in soybean. The relative expression levels of GmNRT1.2a and GmNRT1.2b were higher in leaves, which induced by nitrate and up-regulated with increasing nitrate concentration. GmNRT1.2a and GmNRT1.2b expressions were also induced by rhizobial inoculation and nod factor (NF) treatment. Overexpression of GmNRT1.2a or GmNRT1.2b caused dramatic increment of nodule number. The results provide some data for further investigating the molecular mechanism of GmNRT1.2a and GmNRT1.2b in regulating the symbiotic nitrogen fixation process of soybean.