滨麦草与百萨偃麦草PHR1基因的克隆及序列分析

Cloning and Sequence Analysis of PHR1 Gene from Leymus mollis and Thinopyrum bessarabicum

充分挖掘植物自身磷高效利用的生物学潜力,提高农作物对土壤难溶性磷的吸收和利用效率,对于培育磷高效利用的作物新品种、减少肥料投入和保护生态环境具有十分重要的意义。PHR1基因是植物磷信号调控网络的重要低磷应答转录因子,本研究利用同源克隆的方法,分别从小麦近缘植物滨麦草和百萨偃麦草中克隆获得了其PHR1基因序列。滨麦草Lm PHR1和百萨偃麦草Tb PHR1基因的ORF均为1 356 bp,编码451个氨基酸;与已报道的小偃54A1、B1、D1的PHR1基因高度同源,一致性达到98.63%;对两基因的氨基酸序列进行预测,结果表明它们均具有MYB-DNA结合结构域和一个预测的CC(Coiled coil)结构域;利用Clustal X软件对已报道的水稻、小麦等PHR1基因进行聚类分析并构建系统进化树,结果显示,Tb PHR1基因与二穗短柄草、水稻、玉米、拟南芥的PHR1基因在进化关系上更近一些,而Lm PHR1基因与其他植物的PHR1基因进化关系较远。

To fully explore the plant potential for high- efficiency phosphorus utilization and enhance the plant absorption and use efficiency of insoluble phosphorus in soil will play important roles in breeding new varieties,reducing fertilizer input and protecting agro- ecological environment. PHR1 is an important transcription factor of multiple Pi starvation responses in Pi signaling pathways. By homologous cloning,two PHR1 genes were cloned from Elymus mollis and Thinopyrum bessarabicum,which were named as Lm PHR1 and TbPHR1. Their ORFs were both 1 356 bp,and both of them encoded 451 amino acids; their c DNA sequences shared 98. 63% identity with the c DNA sequences of Xiaoyan 54 PHR1- A1,PHR1- B1,PHR1- D1. Their encoded proteins both had a MYB DNA binding domain and a predicted coiled- coil domain. Using the Clustal X for phylogenetic analysis of the two PHR1 genes with the reported PHR1 genes in rice and wheat,ect. The results showed that PHR1 had closer evolutionary relationship with the PHR1 s from Brachypodium distachyon,Oryza sativa,Zea mays and Arabidopsis thaliana; while the Lm PHR1 had more faraway evolutionary relationship with other plants＇ PHR1 genes.