刺槐Na^+/H^+逆向转运蛋白RpNHX1基因的分离和生物信息学分析(英文)

Isolation and Bioinformational Analysis of Na^+/H^+ Antiporter RpNHX1 Gene from Black Locust

盐分胁迫严重影响植物生长和产量。为了研究木本植物对盐分的适应性,利用5'RACE技术,从刺槐中克隆得到液泡Na^+/H^+逆向转运蛋白基因RpNHX1。该基因长度为2281 bp,含有一个开放阅读框,编码535氨基酸残基组成的蛋白,该蛋白序列与大豆GmNHX1和拟南芥AtNHX1相似,氨基酸的同源性分别达85%和69%,RpNHX1属于NHX亚族的NHX-I分枝。用生物信息学的方法预测RpNHX1具有所有Na^+/H^+逆向转运蛋白共同的结构特点,即含有疏水的N末端,10个跨膜螺旋区域和一个具有调节功能的C端亲水区域,其中氨氯吡嗪咪敏感基序和CaM结合域也是保守的。在4和5的螺旋区域之间,存在有一串带负电荷氨基酸,显示出有规律的排列模式,这些模式在生物界中的Na^+/H^+转运蛋白中是保守的。结合亲疏水资料,我们认为Na^+/H^+转运通道结构可能存在于这一区域。另外,也分析了RpNHX1可能的糖基化、酰基化和磷酸化位点。从这些数据中可以看出,RpNHX1可能在细胞中起到Na^+区隔化作用。

Salinity stress impacts severely plant growth and yield. In order to study wood plant salt adaptability, a vacuolar Na^＋/H^＋ antiporter RpNHX1 gene was cloned from Robinia pseudlacacia L. by 5＇ RACE strategy. The gene is 2 281 bp in length, withan open reading frame encoding a 535 amino acid protein, which is close similar to Glycine max GmNHX1 and Arabidopsis AtNHX1 by 85% and 69% identity respectively, and belongs to NHX-I cluster in NHX subfamily. Bioinformation predicts that RpNHX1 has a common structure in all of Na^＋/H^＋ antiporters, which composed of a hydrophobic N terminus, 10 transmembrane helix region and a regulatory hydrophilic C region, in which an amiloride-sensitive motif and a CaM binding domain are conserved. A tandem of negatively charged amino acid between helix 4 and 5 shows regularly arranged patterns, conservatively presenting in Na^＋/H^＋ transporters among organisms, where a Na^＋/H^＋transport pore structure was proposed combined with its hydropathy profile. Additionally, the glycosylation, N-myristoylation and phosphorylation sites were also examined. From these data, it is thought that RpNHX1 may be competent for Na^＋compaxtmentation in cells.