小麦DHAR基因的克隆及生物信息学分析

Cloning and Bioinformatic Analysis of Wheat DHARGene

以电子克隆和RT-PCR克隆获得了1个小麦脱氢抗坏血酸还原酶(DHAR)基因,并对其编码的蛋白质序列进行了生物信息学分析。结果表明,该基因cDNA序列长1 187bp,编码263个氨基酸,蛋白质分子量为28 908.2Da,PI为6.84;具有GST-N家族和GST-C-DHAR结构域,分别属于硫氧还蛋白超家族和GST-C末端超家族;该蛋白序列无信号肽,是亲水性蛋白,定位于细胞质叶绿体中,二级结构中以无规则卷曲(40.30%)和α螺旋(37.64%)为主,并含有少量的片层结构(17.11%);该蛋白序列与大麦、二穗短柄草、玉米、水稻、拟南芥的同源蛋白序列相似性较高,其中与大麦胞质DHAR(BAJ97007.1)蛋白进化距离最近。

In the study,aDHAR（Dehydroascorbate reductase）gene of wheat was cloned and characterized using the electronic cloning,RT-PCR,and bioinformatics methods.The results showed that the DHAR gene cloned was 1 178 bp,encoding 263 amino acids with molecular weight of 289 08.2Da and PI of 6.84.It contained the GST-N family and the typical GST-CDHAR constructure domain,belonging to the thioredoxin superfamily and GST-C superfamily,respectively.The protein sequence had no signal peptide,belonged to a hydrophilic protein,and was located in the chloroplast.Its secondary structures were mainly the random coil（40.30%）and α-helix（37.64%）as well as a small amount of extended strands（17.11%）.It had higher sequence similarities with those of other plants,including Hordeum vulgare,Brachypodium distachyon,Zea may,Oryza sativa,Arabidopsis thaliana and so on,among which its evolution distance was closest to that（BAJ97007.1）of Hordeum vulgare.