农业生物技术学报2011，Vol.19Issue(4)：634-641,8.DOI:10.3969/j.issn.1674-7968.2011.04.006
莲藕多酚氧化酶基因(PPO)的克隆与表达分析
Cloning of Polyphenol Oxidase Gene(PPO) from Lotus Rhizome Bud and Its Expression in Different Tissues
摘要
Abstract
In order to obtain the fall-length sequence of polyphenol oxidase gene (PPO) and its expression in different tissues, it was cloned from lotus rhizome (Nelumbo nucifera Gaertn. Ssp. Nucifera) bud by using RACE technique. The fall length cDNA of PPO was 2 074 bp with open reading frame 1 503 bp, encoding a protein of 501 amino acids, 5TJTRs of 160 bp and 3TJTRs of 411 bp (GenBank No. HQ380894). Bioinformatics analysis showed that the molecular weight of PPO gene was 56.8 kD with pI value 8.60, which had tryosinase family domain, hydrophilic characteristics and trans-membrane properties but no signal peptide. Both a-helix and β-turn were found spreading in the whole polypeptide chain. The expression of PPO gene in five lotus tissues (rhizome bud, young leaf, petal, fresh rhizome cut and stem) was also investigated and the variance analysis results showed that the relative expression level of PPO in rhizome bud was only slightly higher than that in young leaf, but significantly higher than those in the other three tissues. The expression level in young leaf was no difference with that in fresh rhizome cut, but significantly higher than both in petal and stem. The expression levels in petal and stem were lowest and no significance between them. These results indicate that PPO gene produced in rhizome bud(an important meristem) may have no activity or be unstable, which is distributed to different tissues after production accompanying with organ development and responsible for corresponding functions under specific spatial and temporal conditions.关键词
莲藕/多酚氧化酶/基因克隆/序列全长/基因表达Key words
Neumbo nucifera Gaertn.ssp.nucifera/Polyphenol oxidase (PPO)/Gene clone/cDNA sequence/Gene expression引用本文复制引用
张跃进,郝晓燕,梁宗锁,林文超,郭宏波..莲藕多酚氧化酶基因(PPO)的克隆与表达分析[J].农业生物技术学报,2011,19(4):634-641,8.基金项目
本研究由西北农林科技大学人才基金(No.Zl110828)资助 （No.Zl110828）
