二色补血草硫氧还蛋白过氧化物酶基因LbTPx的克隆及其表达

Cloning and Expression of a Thioredoxin Peroxidase Gene LbTPx from Limonium bicolor

从二色补血草(Limonium bicolor)cDNA文库中分离出一个新的硫氧还蛋白过氧化物酶基因(LbTPx)全长cDNA序列。基因全长1 016 bp,其中:5’非翻译区146 bp,3’非翻译区69 bp,开放读码框(ORF)801 bp,共编码266个氨基酸;编码蛋白的分子质量为47.99×10-24kg,理论等电点为(pI)8.83。利用荧光定量PCR方法研究了二色补血草LbTPx基因在NaCl、ABA、CuSO4、ZnCl2和CdCl2胁迫下不同时间的表达模式。结果表明:NaCl和CuSO4处理均能诱导LbTPx基因在二色补血草根和叶中的表达;ABA、ZnCl2和CdCl2处理则只能诱导LbTPx基因在二色补血草叶中的表达,而抑制其在二色补血草根中的表达。

The full length eDNA of a novel Thioredoxin Peroxidase （LbTPx） gene was cloned from a eDNA library of Limonium bicolor. The LbTPx gene cloned is 1 016 bp in length, which includes a 146 bp of 5＇ untranslated region （UTR） and a 69 bp of 3＇ untranslated region. This gene has an open reading frame （ORF） of 801 bp in length, encoding a protein of 266 amino acid residues with the molecular mass of 47.99× 10^-24 kg and theoretical pI of 8.83. The expression of LbTPx gene in L. bicolor in response to NaCl, ABA, CuSO4, ZnCl2 and CdCl2 was further investigated using real time quantitative PCR. In both leaf and root of L. bicolor, the expression of LbTPx was induced by NaC1 and CuSO4. ttowever, the expression of LbTPx was induced in leaf and inhibited in root of L. bicolor under ABA, ZnCl2 and CdCl2 stresses.