水稻硝酸还原酶的RNA干涉及其酶活性分析

RNA Interference of Nitrate Reductase and Analysis of Nitrate Reductase Activities in Rice

分析水稻硝酸还原酶(NR)基因生物信息学的结果显示:水稻基因组中有2个NR基因成员:一个为NR[NADH](NR1);另一个为NR[NAD(P)H](NR2)。两者的蛋白序列相似性为70%。用RT-PCR技术从水稻cDNA中获得了NR1和NR2的cDNA片段,其大小分别为1086bp和892bp。构建RNA干涉载体(称pRNAi-NR1和pRNAi-NR2)转化水稻愈伤组织后检测转基因后代酶活性的结果表明:两种干涉植株的根叶中的NR活性均大幅度下降,并且根叶中的活性变化呈线性正相关关系。表明2个基因可能均有调控根叶中NR活性的作用。

Bioinformatic analysis showed that there were two members of NR genefamily in rice genome. One have been annotated as NR[NADH] （NR1）, the other is named as NR[NAD（P）H] （NR2）. There were more than 70% similarities between NR1 and NR2 protein sequences. Both NR1 and NR2 cDNA fragments were obtained by RT-PCR, with 1 086 bp and 892 bp, respetively. Then cDNAs were constructed into two interference vectors, named as pRNAi-NR1 and pRNAi-NR2, respectively. NR activities were measured in roots and leaves of the two kind transgenetic plants harbouring interference NR1 or NR2 genes. The results showed that NR activities were significantly decreased in leaves and roots of both transgenic plants, and there was a positive correlation between NR activities in leaves and roots. Our data suggested that the NR1 and NR2 genes may play an important role in controlling NR activities in leaves and roots.