摘要： 半定量RT-PCR分析表明,水稻胚胎发育后期丰富蛋白基因OsLEA19a在水稻幼苗中的表达受干旱和高盐的诱导,说明OsLEA19a可能在水稻抗旱和抗盐中发挥作用。利用RT-PCR方法成功从水稻中克隆了OsLEA19a的cDNA。生物信息学分析表明,OsLEA19a基因编码一个由200个氨基酸残基组成的蛋白,蛋白分子量为20.48 kDa,等电点为5.89。OsLEA19a蛋白的5～48位氨基酸残基形成LEA₄结构域。OsLEA19a蛋白的二级结构有3个α-螺旋构象区域,没有伸展的β-片层构象,为亲水蛋白。进化树分析表明,OsLEA19a与单子叶植物第3组LEA蛋白的亲缘关系较近,而与双子叶植物的较远,OsLEA19a与单子叶植物第3组LEA蛋白的氨基酸一致性为48%～57%。

关键词: 水稻, OsLEA19a, 克隆, 表达特性, 生物信息学

Abstract: Semi-quantitative RT-PCR analysis revealed that OsLEA19a，a late embryogenesis abundant(LEA) protein gene，was induced by water deficit and salt stress，which sugGested a role for OsLEA19aprotein in water deficit and salt stress protection． The cDNA sequence of OsLEA19awas cloned from rice by RT-PCR． Bioinformatics analysis showed that OsLEA19aencoded a protein of 200 amino acids with a calculated molecular mass of 20． 48 kDa and a theoretical pI of 5． 89． OsLEA19aprotein contains a Pfam: LEA_4 domain architecture at position 5-48， three α-helical domains and without β-sheet domain． In silico predictions showed OsLEA19aprotein was strongly hydrophilic． The phylogenetic relationship between related group 3 LEA proteins from different plants was analyzed， which showed that OsLEA19awas more closely related to group 3 LEA proteins from monocots than from dicots． The amino acid sequence of OsLEA19ashows 48%-57% sequence identity with other members of group 3 LEA proteins from monocots．

Key words: Rice, OsLEA19a, Molecular cloning, Expression character, Bioinformatics

中图分类号: 

• Q78