水稻Cu/Zn-SOD基因的克隆、表达及生物信息学分析

Cloning, Expression and Bioinformatic Analysis of Cu/Zn-SOD Gene in Rice

为了探究水稻铜锌超氧化物岐化酶基因(OsCu/Zn-SOD)的功能,以水稻品种日本晴(Oryza sativa japonica)为材料,采用同源克隆法获得OsCu/Zn-SOD,并对其进行表达及生物信息学分析。结果表明,OsCu/Zn-SOD基因cDNA序列为606 bp,编码152个氨基酸,CDS区459 bp,碱基组成A为22.7%、T为24.4%、G为29.4%、C为23.5%。OsCu/Zn-SOD蛋白表现为弱酸性,且稳定、亲水;二级结构中以无规则卷曲和延伸链结构为主,三级结构同源建模成功,主要是螺旋和转角;亚细胞定位OsCu/Zn-SOD主要分布在细胞质中,推测可能在翻译、运输结合和能量代谢过程中发挥重要作用,无跨膜结构域,无信号肽;该蛋白序列中存在8个丝氨酸磷酸化,4个苏氨酸磷酸化位点。进化分析表明,克隆的OsCu/Zn-SOD氨基酸序列与玉米、短柄草的同源关系较近,具有较高的保守性,与小立碗藓的同源关系较远。RT-PCR分析表明,OsCu/Zn-SOD基因在各组织中均有表达,水稻孕穗期中茎的表达最高,其次分别为叶和穗,根中表达量最低。本研究为进一步研究OsCu/Zn-SOD在水稻抗逆中的作用提供了重要的帮助。

In order to explore the function of Cu/Zn Superoxide Dismutase Gene（OsCu/Zn-SOD） in rice, OsCu/Zn-SOD was obtained by homology cloning method, and was further carried out with expressions and bioinformatic analysis with Oryza sativa as the material. The result showed that the cDNA sequence of OsCu/Zn-SOD was 606 bp, encoding a protein of 152 amino acids. The CDS region of OsCu/Zn-SOD was 459 bp whose compositions of basic group were 22.7% of A, 24.4% of T, 29.4% of G and 23.5% of C. The OsCu/Zn-SOD protein was stable, hydrophilic and mildly acidic, with random coil and extended strand as the main components in secondary structure, and the 3 D model was successfully constructed, and spatial structure was mainly the spiral and the rotation angle. Subcellular localization of OsCu/Zn-SOD was mainly distributed in the cytoplasm and nuclei without transmembrane region and signal peptide, which OsCu/Zn-SOD mainly played a role in the processes of translation, transport and binding, and energy metabolism. The protein sequence included eight serinephosphorylation sites and fou r threonine phosphorylation sites. Further phylogenic analysis displayed that the cloned OsCu/Zn-SOD amino acid sequence had higher conservatism which showed close genetic relationship with Zea mays and Brachypodium distachyon, and far genetic relationship from Physcomitrella patens. The RT-PCR analysis indicated that the Cu/Zn-SOD gene expressed in all tissues. The highest expression levels were found in stem, followed by the leaves and tassel, respectively, with the lowest expression in the root. The study might provide important help for the further study on the role of OsCu/Zn-SOD in rice resistance.