一个大豆质子转运体GmMRP5的克隆与表达分析

Cloning and Expression Pattern Analysis of a Proton Transporter GmMRP5 in Soybean

为探明大豆中MRP蛋白基因的作用机理,从大豆材料中克隆到GmMRP5基因完整的编码序列,GmMRP5基因的开放阅读框(ORF)全长4 479 bp,编码1 492个氨基酸。序列比对与进化树分析表明:GmMRP5拥有13个推断的跨膜结构域(TMD)和典型的ABC转运蛋白保守结构域,系统进化树分析表明,GmMRP5与AtMRP5同缘关系最近,同属于ABC转运蛋白家族C亚家族;该基因是组成型表达基因,在大豆的根、茎、叶及荚中均有表达;经不同浓度脯氨酸和柠檬酸处理后,该基因在大豆根中的表达被强烈诱导并高效表达。Real-Time PCR结果表明,该基因在酸性缓冲液处理后表达量上调,推测其作为质子转运体参与大豆阴阳离子交换反应。

In order to investigate the mechanism of the MRP protein genes in soybean ,a novel soybean gene GmMRP5 was identified in soybean cultivar.GmMRP5 containing an open reading frame ( ORF) of 4 479 bp nucleo-tides.The ORF encoded a protein of 1 492 amino acids.Sequence alignment and evolutionary tree clustering analy-sis showed that GmMRP5 contains 13 putative transmembrane-spanning domains(TMDs)and ABC transport protein conserved domain .Phylogenetic tree analysis showed that Gm MRP5 was closely related to AtMRP5 and both be-longed to ABCC subfamily .GmMRP5 was a constitutive expression gene and expressed in root ,stem and leaves by using Real-Time PCR analysis in soybean .GmMRP5 was strongly induced and highly expressed in root after treat-ment by proline and citrate solution .Real-Time PCR showed the expression level of GmMRP5 was increaced by dif-ferent pH buffer solution treatment ,suggesting that GmMRP5 gene may be as a proton transporter to participate in the stress response in soybean .