紫竹PPO基因的生物信息学及表达分析  

Bioinformatic Analysis and Expression of PPO Gene in Phyllostachys nigra

作　　者：关鹰[1] 王弋[1] 郭小勤[1] 林新春[1] 方伟[1] 

机构地区：[1]浙江农林大学 亚热带森林培育国家重点实验室培育基地,浙江临安311300

出　　处：《浙江林业科技》2013年第2期10-14,共5页Journal of Zhejiang Forestry Science and Technology

基　　金：浙江农林大学科研发展基金面上项目(2007FR025);浙江省科技厅(2007C22081)

摘　　要：以紫竹(Phyllostachys nigra)一年紫嫩叶的cDNA为材料获得一个多酚氧化酶基因(命名为PnPPO1)片段,测序显示,该序列长438 bp,该片段编码有146个氨基酸残基组成的多酚氧化酶保守区,该区域包含CuB结合区,其编码的蛋白属于酪氨酸酶(tyrosinase)。Blastp分析显示,该氨基酸序列与小麦(Triticum aestiv)、水稻(Oryza sativa)中的多酚氧化酶有很高的同源性。该蛋白片段分子量约为36.2 kD,pI为5.03。比对一年紫和台湾紫中该基因的序列发现,两者同源性为84.45%,两者间还存在明显的SNP位点会导致酶切点位发生变化和新酶切位点的产生。RT-PCR分析结果表明,PnPPO1基因在叶芽中表达最高,鞭根中微量表达,其余供试组织中未检测到其表达。Partial sequence of polyphenol oxidase（PPO） gene （named PnPPOI） was obtained by homologous cloning from the immature leaf of Phyllostachys nigra. Analysis of the sequence showed that it was 438bp, which encoded a protein of 146 amino acid residues and was highly similar with those in wheat and rice. Bioinformatic analysis showed that the molecular weight of PnPPOl was 36.2 kD with pI value of 5.03. The putative PnPPO1 fragment had CuB structural domain and belonged to tyrosinase family. SNP sites were discovered through alignment sequence between PnPPOI and PnPPO. Those SNP could result in the alteration of enzyme cutting sites in these two PPO genes in Pk nigra. Meanwhile, the result of RT-PCR showed that PnPPOI was expressed the highest in leaf bud and a little in root, but was not detected in other sample tissues.

关 键 词：紫竹 PPO基因 多酚氧化酶 单核苷酸多态性 

分 类 号：S718.46[农业科学—林学]