烟草类胡萝卜素异构酶基因的电子克隆及生物信息学分析

Electronic Cloning and Bioinformatics Analysis of Carotenoid Isomerase Gene in Tobacco

为从烟草中克隆烟草类胡萝卜素合成途径中的关键类胡萝卜素异构酶基因,运用电子克隆的方法,以番茄CRTISO基因为探针,分离编码CRTISO基因的cDNA序列,并对其进行序列分析。结果表明:该基因编码区为1 716bp,编码571个氨基酸残基。烟草CRTISO蛋白为亲水性稳定蛋白,相对分子量为61.65kDa,理论等电点为8.48,蛋白质二级结构中的主要构成元件是α-螺旋和无规则卷曲。NtCRTISO蛋白含有16个丝氨酸激酶磷酸化位点,5个苏氨酸激酶磷酸化位点,3个酪氨酸激酶磷酸化位点,定位在线粒体内膜的概率为0.721。系统进化树分析表明,烟草CRTISO与其他高等植物类胡萝卜素异构酶亲缘关系比较近。

In order to clone a critical enzyme carotenoid isomerase gene in carotenoid biosynthesis of tobacco,a cDNA sequence of encoded CRTISO gene was isolated from tobacco by electronic cloning with probe of tomato CRTISO gene sequence.Sequence analysis result showed that the gene contained a full coding region of 171 6 bp encoding 571 amino acid residues with a molecular mass of 54.21 kDa and isoelectric point of 8.48.Main components in secondary structure of CRTISO protein in tobacco were α-helix and random coil.CRTISO protein contained 16 serine kinase phosphorylation site,5 threonine kinase phosphorylation site,and 3 tyrosine kinase,the probability of locating on inner mitochondrial membrane was 0.721.Phylogenetic analysis result indicated that CRTISO in tobacco had closer genetic relationship with carotenoid isomerase of other higher plants.