蝴蝶兰抗坏血酸过氧化物酶基因克隆及其表达研究

从蝴蝶兰（Phalaenopsis）中克隆获得了抗坏血酸过氧化物酶基因（APX）同源序列，命名为PhAPX（GenBank登录号为：FJ161977）。PhAPX cDNA全长为1 320 bp，完整的编码框为747 bp，编码249个氨基酸。生物信息学分析结果表明，PhAPX属于过氧化物酶家族ClassⅠ的成员，PhAPX蛋白可能是胞质型APX，与其他植物的APX相似性较高。real-time PCR分析表明PhAPX是一个广谱表达的基因，在蝴蝶兰根、茎、叶、花等各个部位都有表达。机械伤害和盐处理都可以诱导PhAPX表达上调，表明PhAPX在胁迫防御中起作用。

Molecular Clonging and Expression Analysis of Homological Gene APX from Phalaenopsis

The APX homolog sequence,PhAPX(GenBank accession No. FJ161977)was cloned from Phalaenopsis plant. The full length cDNA of PhAPX was 1 320 bp,has an open read frame of 747 bp, encoding a protein of 249 amino acids. Bioinformatic analysis showed that PhAPX protein shared the characters of ClassⅠof peroxidase family. Amino acids sequence analysis suggested that PhAPX protein might locate in cytoplast and PhAPX was highly similar to other APX proteins. Real-time PCR analysis showed that PhAPX mRNA,a broad-spectrum expression gene,was expressed in the organs in Phalaenopsis including root,stem,leaf and flower. PhAPX was also found to be up-regulated by wound and NaCl,which suggested that it might play a role on stress.