【摘要】 以水稻(Oryza sativa)品种Cpslo17幼穗为材料,通过RT-PCR克隆了长度为698bp的编码水稻细胞质铜锌超氧化物歧化酶基因(OsCu/Zn-SOD)。序列分析表明其覆盖基因完整编码框,编码由152个氨基酸组成的蛋白,它与玉米(Zea maize)Cu/Zn-SOD基因序列的相似率为88%。TargetP和ChloroP预测编码蛋白N端无信号肽序列,且此编码区段有8个外显子和7个内含子。利用Swiss-Model站点预测OsCu/Zn-SOD三维结构,并分析其铜锌离子结合位点的结构。RT-PCR结果表明OsCu/Zn-SOD在水稻不同品种均有表达,但表达量存在差异,OsCu/Zn-SOD在Cpslo17的分裂旺盛的幼嫩组织如幼穗、开花期花序和未成熟种子中表达量较高,而在叶片中表达量相对较低,在愈伤组织中表达微弱。更多还原

【Abstract】 The 698 bp cytoplasmic copper/zinc-superoxide dismutase gene (OsCu/Zn-SOD) was cloned by RT-PCR from young panicles of rice Cpslo17, a wide-compatible rice cultivar (Oryza sativa). DNA sequence analysis indicated that the gene consisted of a full-open reading frame and encoded a protein of 152 amino acid residues. The nucleatide sequence of OsCu/Zn-SOD shares 88% identity to maize Cu/Zn-SOD. No signal peptide was predicted by TargetP and ChloroP. Further analysis of encoding segment of OsCu/Zn-SOD revealed that it contained 8 exons and 7 introns. The putative three-dimensional structure of OsCu/Zn-SOD was predicted by the Swiss-Model server and Cu2+ and Zn2+ binding sites of OsCu/Zn-SOD were analyzed. RT-PCR results showed differential expression of OsCu/Zn-SOD in leaves of both japnica and indica rice. OsCu/Zn-SOD was expressed highly in panicles during young ear and the flowering stages or in immature seeds, however less in leaves and faintly in callus.更多还原